Simons Myofascial Pain & Dysfunction-The Trigger Point Manual Vol 2-The Lower Extremities

["Chapter 7 \/ Gluteus Maximus Muscle 133 1. REFERRED PAIN to the false conclusion that the deeper (Fig. 7.1) gluteal muscles are involved. The TrP2 is likely to refer pain that covers the entire Myofascial trigger points (TrPs) in the lower sacrum and projects laterally below gluteus maximus muscle refer pain lo- the crest of the ilium. Pain from TrP2 does cally in the buttock region and rarely, if not include the anal region or coccyx. ever, to the considerable distance charac- Pressure on TrP2 can produce such in- teristic of TrPs in the deepest gluteal mus- tense local pain when the patient sits on a cle, the gluteus minimus (Chapter 9 ) . 7 4 , 8 6 hard seat that, depending on the sitting position, he or she may feel as if a nail is There are three common sites of TrPs in pressing into the bone. the gluteus maximus muscle. The com- posite pain pattern for these TrPs has Gluteus maximus TrP3 (Fig. 7.1C) is lo- been reported previously.73, 75 cated in the most medial and inferior muscle fibers. These fibers lie close to the Myofascial TrPs of the gluteus max- coccyx, to which this TrP refers pain. imus, found adjacent to the sacrum in the Therefore, TrP3 is a source of coc- region marked TrP1 in Figure 7.1A, refer a cygodynia, which also may arise from crescent of pain and tenderness beside TrPs in the coccygeus muscle (Chapter 6). the gluteal cleft. The upper end of this pain pattern includes the sacroiliac joint. The patients with pain referred to the A patch of pain along and above the glu- coccyx from gluteus maximus TrP3 fre- teal fold may spill over slightly onto the quently insist that there is pressure on the adjacent posterior thigh. Apropos of glu- coccyx when they are sitting, because that teus maximus TrPa, Kelly44 noted that a is where it hurts. However, ordinarily, the tender muscular lesion of the gluteus coccyx does NOT touch the chair seat; one maximus in the sacroiliac region caused can easily slip a finger between the coc- low backache, and Lange47 observed that cyx and the seat, except when the indi- myogelosis at the origin of the gluteus vidual slumps down in the chair to re- maximus along the medial crest of the il- cline the torso. A rubber ring or \\\"dough- ium caused lumbago. nut\\\" is often prescribed to relieve this nonexistent coccygeal pressure; however, The TrP2 region (Fig. 7.16), slightly the rubber ring can aggravate the pain if it above the ischial tuberosity, is the most concentrates pressure on TrP3. More ef- common location of TrPs in the gluteus fective use of this device is described in maximus muscle. Myofascial TrPs in this Section 14. area usually refer pain to the entire but- tock and also refer tenderness deep within the buttock, which can easily lead Figure 7.1. Referred pain patterns (solid red and lower midportion overlying the posterior surface of the ischial tuberosity (TrP2). C, the most medial inferior stippled areas) of trigger points (TrPs) (Xs) in the glu- portion (TrP3). D, location of TrP1, TrP2 and TrP3 in the teus maximus muscle. Trigger points are located in: A, gluteus maximus muscle. the superior medial portion of the muscle (TrP,). B, the","134 Part 1 \/ Lower Torso Pain A few authors identified tender spots in Gluteus the gluteus maximus muscle as the origin medius of sciatica or sciaticlike pain.32,35,44,45,47 These writers may have been describing Gluteus TrPs in the posterior part of the gluteus maximus minimus, which can refer sciaticlike pain down the back of the thigh and the calf (Chapter 9). None of these authors ap- pears to have distinguished specifically among the three gluteal muscles, as de- scribed below in the section on Differen- tial Diagnosis and as described in the next chapter. We have not observed a sciat- iclike referred pain pattern from gluteus maximus TrPs. Occasionally, one finds TrPs located in the gluteus maximus along its lateral bor- der or along its attachment to the crest of the ilium. These TrPs also refer pain and tenderness chiefly over the muscle itself. The referred tenderness in the regions that match the pattern of referred pain causes the patient to point out these refer- ence zones as painful spots because they hurt when pressed or bumped. As empha- sized by Kelly43, these zones of referred tenderness should be clearly distin- guished from their TrP origins and not treated as primary sites of pain. 2. ANATOMICAL ATTACHMENTS AND Figure 7.2. Attachments of the right gluteus max- CONSIDERATIONS imus muscle (red) in the posterolateral view. The glu- (Fig. 7.2) teus maximus muscle covers the posterior portion of the gluteus medius muscle, but not its anterior portion. From an evolutionary point of view, up- the intelligence and unique manual dex- right walking by true bipedal plantigrade terity of humans.6 progression has been singled out as the unique feature of human locomotion.38 Anatomically, the gluteus maximus Humans alone, among mammals, can forms the prominence of the buttock and place the center of gravity of the head, is a remarkably large muscle. It is twice as arms, and torso over the hips.6 This func- heavy (844 gm) as the gluteus medius and tion has been associated with evolution- gluteus minimus together (421 gm),97 and ary changes in the skeleton and glu- it often measures more than 2.5 cm (1 in] teus maximus muscle that are uniquely in thickness. Proximally, it attaches to human. These changes include shorten- the posterior border of the ilium and to ing and tilting of the pelvis to permit ex- the posterior iliac crest, the posterolateral tension of the thigh at the hip to 180\u00b0, an- surface of the sacrum, the side of the coc- gulation of gluteus maximus fibers more cyx, the aponeurosis of the erector spinae horizontally,6 and enlargement of the muscles, the length of the sacrotuberous muscle to more than twice the size of the ligament, and to the fascia covering the gluteus medius.63 These evolutionary gluteus medius muscle (Fig. 7.2). Dis- changes, which were well illustrated by tally, about three-fourths of the muscle Hunter,37 presumably freed the hands for (all of its upper fibers and its superficial other activities and were considered by lower fibers) attaches to the thick tendi- Bollet to be crucial to the development of nous aponeurotic sheet that crosses the greater trochanter and joins the iliotibial","Chapter 7 \/ Gluteus Maximus Muscle 135 band of the fascia lata. The remaining alis in 58% of cases, the extensor coccygeus later- deep lower fibers of the gluteus maximus alis in 43%, and the abductor coccygeus dorsalis are attached to the gluteal tuberosity of in 87%. These dorsal coccygeal muscles, although the femur between the attachments of the usually vestigial, may attain considerable bulk in vastus lateralis and adductor magnus some people; their TrPs cause coccygodynia. muscles;9,78 the more horizontal course of these posterior deep fibers is clearly de- Autopsy samples of normal adult gluteus max- picted elsewhere.68 The most distal fibers imus muscles from individuals under age 44 years of the gluteus maximus that arise from the showed that 68% of fibers were slow-twitch (type coccyx originate embryologically as a sep- 1) and 32% were fast-twitch (type 2) muscle fi- arate muscle and fuse with the sacral por- bers. The muscle had essentially the same compo- tion before birth.81 sition in two groups of persons older than 44 years: 70% of the fibers were type 1 and 30% were The large trochanteric bursa separates type 2. Although individual variability was great, the flat tendon of the gluteus maximus the percentage of type 1 fibers (which depend muscle from the greater trochanter.21 An largely on oxidative metabolism) always exceeded inconstant ischial bursa permits smooth the number of type 2 (rapidly fatiguing) fibers that gliding of the muscle over the ischial tu- utilize chiefly glycolytic energy pathways.76 berosity. A third bursa separates the glu- teus maximus tendon from that of the vas- Supplemental References tus lateralis muscle.9,24 Other authors illustrate the gluteus maximus mus- Apropos of TrP2, which is located in cle as seen from behind,1,12,26,64,68,70,77 from behind the lower border of the gluteus maximus with overlying nerves,53 obliquely from behind,85 close to the ischial tuberosity, it should from the side,18,69,83 from the side with overlying be noted that the muscle covers the tuber- nerves,80 from below,3,9,66 and as seen in sagittal osity when a person stands or walks, but section.23,52 Other illustrations map its bony at- slides upward when he or she is seated. tachments,27 schematically portray its bony at- The ischial tuberosity in the upright tachments and fiber direction,2, 68 and show its at- seated posture is padded by fibrous tis- tachment to the iliotibial tract distally.54,61 It is sue, skin, and sometimes a bursa,79 but portrayed in cross sections through the prostate,65 not by muscle (this is easily confirmed by the head of the femur,67 the distal part of the hip palpating the tuberosity while seated). joint,25 at the neck of the femur,62 at the apex of However, as one slouches down on the the femoral triangle,10 and in eight equally spaced seat and reclines further against the back- cross sections.8 It is seen in coronal section rest, the hip extends, the muscle slides through the femoral heads.87 down, and the weight-bearing region shifts upward around the curve of the is- 3. INNERVATION chial tuberosity. At some point, the mus- cle and pressure meet, compressing TrP2. The gluteus maximus muscle is inner- vated by the inferior gluteal nerve, which Several external coccygeal muscles with vari- arises from the dorsal portions of spinal roots L5, Si, and S2. This nerve usually ex- able degrees of development may lie adjacent to its the pelvis through the restricted space of the greater sciatic foramen between the the medial (posterior) fibers of the gluteus max- piriformis muscle and the sacrospinous ligament; it is accompanied by the infe- imus. The sacrococcygeus dorsalis muscle,4,11,16 rior gluteal artery and vein. The nerve then passes between the gluteus medius when present, may span as many as five sacral and gluteus maximus muscles, and inner- vates the gluteus maximus through its and one or two coccygeal vertebrae, as illustrated deep surface. In 15% of 112 subjects, the inferior gluteal nerve exited the pelvis by Toldt.84 It often attaches proximally to the pos- through, instead of below, the piriformis muscle en route to the gluteus maximus terior inferior iliac spine.16 How frequently it is muscle. In every such case, the peroneal branch of the sciatic nerve accompanied found depends on how carefully the caudal mus- the inferior gluteal nerve through the piri- formis muscle.82 culature is dissected. Eisler16 reports that, in three series of dissections, this muscle was found in one of 36, one of 16, and two of 122 bodies, respec- tively. In contrast, Lartschneider48 (cited by Eisler) considered it a normal structure because it was missing in only six of 100 adult cadavers. Lartschneider48 also found remnants of three \\\"tail- wagging\\\" muscles: the extensor coccygeus medi-","136 Part 1 \/ Lower Torso Pain 4. FUNCTION During quiet ambulation, limited elec- tromyographic (EMG) activity appears When the foot is fixed, the gluteus chiefly in the upper and lower parts of maximus muscle frequently functions the gluteus maximus in a biphasic pattern through lengthening contractions to con- with one small peak near the end of trol (decelerate or restrain) movement, swing phase and the other peak at heel such as when an individual is stooping, strike. Motor unit activity in the middle bending, sitting down from a standing po- part of the muscle is likely to be triphasic sition, or descending stairs. During ambu- with an additional peak from terminal lation, this muscle functions shortly after stance to immediately after toe-off.5 These heel-strike to restrain the tendency to- findings are highly variable among indi- ward hip flexion. It also helps regain viduals.50 The lower portion of the glu- body position over the forward foot and teus maximus appears to be the part that stabilizes the pelvis. In some activities, functions primarily to stabilize the flexed the gluteus maximus undergoes a short- hip during the stance phase in ambula- ening contraction to assist extension of tion. Greenlaw34 reported detailed analy- the trunk indirectly through its pull on sis of gluteus maximus activity during the pelvis. ambulation and other movements. During locomotion, electrical activity of the glu- Actions teus maximus consistently increases in intensity and duration with increased rate When tested with the pelvis fixed and the and load. lower limb free to move, the gluteus max- imus muscle is active only when moder- One study showed electrical activity to ate to heavy efforts are exerted in the be maximum during stair ascension and movements classically ascribed to this to disappear during stair descension.50 muscle.59 It can powerfully assist exten- Gluteus maximus activity showed no re- s i o n 5 , 9 , 1 9 , 3 4 , 6 3 and lateral rotation5,9 1 9 , 6 3 of markable difference when subjects wore the thigh at the hip. During balanced high heels as compared with low heels.41 standing and easy walking, the gluteus maximus shows minimal activity.5,20,34, 36 The gluteus maximus is not usually It is more active during running and used in relaxed sitting, squatting, and jumping.9,36, 42 quiet standing,28 including swaying for- ward at the ankle while standing.40 This All fibers of the muscle extend and lat- muscle braces the fully extended knee by erally rotate the thigh.9 Abduction of the acting through the iliotibial tract.9 Less thigh is assisted primarily by the upper fi- than 10% of its maximum activity is ob- bers;30 the lower fibers help to abduct the served when the subject is standing and thigh against heavy resistance with the bending forward at the hips, and while thigh flexed.5 kneeling.28,58 Functions The gluteus maximus shows considera- bly more activity when the subject lifts a An understanding of the specific func- load from the floor while using the safer tions of the gluteus maximus helps the straight-back, flexed-knee posture than it clinician and the patient identify activi- does when employing a forward-flexed, ties and stress situations that may have straight-knee lift (Fig. 22.16).56 initiated and then perpetuated TrPs in this muscle. This largest of the gluteal muscles was reported to be inactive during exercise on Activity of the gluteus maximus that a stationary bicycle.28 Another study17 re- reaches only 30% of its maximum con- ported minimal electromyographic evi- tractile force can be supported by aerobic dence of activity during bicycling; while metabolism. This level of activity does this activity increased with increased not depend on anaerobic metabolism, workload and pedalling rate, it showed which depletes the muscle's energy no remarkable difference with change in reserves and is only l\/13th as efficient as saddle height or with use of a posterior aerobic metabolism.50 foot position on the pedal.17 The gluteus maximus becomes active, but is less active than the hamstrings,","Chapter 7 \/ Gluteus Maximus Muscle 137 during 13 vigorous sport skills7 and when lower gluteus maximus fibers and has ad- jumping.42 The observation that, electro- jacent attachments, is a partner of the glu- myographically, the hamstrings are more teus maximus in lateral rotation of the active than the gluteus maximus in pro- thigh. ducing hip extension during ambulation and running may relate to the fact that the Antagonists to the extensor function of hamstrings are two-joint muscles that the gluteus maximus at the hip are the have nearly twice the skeletal leverage hip flexors, chiefly the iliopsoas and rec- available at the hip than at the knee in the tus femoris muscles. The hip adductors walking position.50 are the chief antagonists to the lateral ro- tation function of the gluteus maximus With the lower limb fixed and the pel- and to the abduction function of its up- vis free to move, as when rising from the permost fibers. The tensor fasciae latae seated position,36 climbing stairs, or walk- opposes the lateral rotation and extension ing up a grade,36 the gluteus maximus as- effects of gluteus maximus contraction, sists extension of the trunk through trac- although the two muscles share abductor tion on the pelvis.9 Activity in this mus- function and share a common attachment cle increases as the standing individual to the fascia lata. leans forward and flexes at the hip to about 45\u00b0.63 Sudden forward-flexion move- 6. SYMPTOMS ments at the hip are checked by the glu- teus maximus.57 When the thigh is fixed, Pain referred from most gluteus maximus this muscle forcefully tilts the pelvis pos- TrPs is aggravated by walking uphill, es- teriorly (rocks the pubis anteriorly), as pecially in the forward-bent posture. Pain during sexual intercourse. from TrPs in this muscle is intensified by vigorous contraction in the shortened po- During vigorous back extension in the sition, as when swimming the crawl prone position, the gluteus maximus be- stroke. This cramp pain is more likely to comes moderately active as an assistant to occur in cold water. In deep water, the other muscles.59 development of cramps together with this pain can be paralyzing and life-threaten- Absence of the gluteus maximus due to ing. disease15 or to surgery36 causes no limping during ordinary ambulation and little im- Patients with an active TrP2 near the is- pairment of several ordinary activities. chial tuberosity are often uncomfortable Compared with the intact side, only slight and restless when seated. Patients with reduction in isometric and isokinetic hip coccygodynia that is referred from TrP3 extension strength (6% and 19%) oc- may be observed to squirm during pro- curred unless the hamstrings had also longed sitting in an attempt to avoid the been removed.51 This remarkable reten- local tenderness and referred pain pro- tion of strength probably reflects compen- duced by pressure on the TrPs. The con- satory hypertrophy of the hamstring mus- nective tissue and skin over the ischial tu- cles. berosity become uncomfortably ischemic after prolonged upright sitting. As the in- 5. FUNCTIONAL (MYOTATIC) UNIT dividual slides down and forward on the seat to decrease this pressure, weight is The longissimus and iliocostalis are long increased on TrP2 as described previously paraspinal muscles that work closely in Section 1. Since neither seated posi- with the hamstrings and the gluteus max- tion gives relief, no chair seems comfort- imus; functioning together as a unit, they able. extend the trunk. Together, they help re- store upright posture from forward flex- Differential Diagnosis ion in the standing position and help exe- cute forced extension of the back and hip. Gluteus maximus TrPs are distinguished The hamstrings (except the short head of from TrPs in the underlying gluteus the biceps femoris) and the posterior por- medius and gluteus minimus muscles by tions of the gluteus medius and minimus their topographical location in the but- also extend the thigh at the hip. The piri- tock, by the distribution of the referred formis muscle, which is parallel to the pain, by the depth of TrP tenderness and","138 Part 1 \/ Lower Torso Pain direction of palpable bands, and by what with 3 mL of 1% lidocaine80 or 3 mL of movement is restricted. lidocaine-methylprednisolone solution71 caused prompt and marked reduction of The topographic relationships of the the clinical manifestations of bursitis.80 three gluteal muscles are drawn in Figure 8.5. The most inferior gluteus maximus fi- It is possible that some persons with bers are distal to the other gluteal mus- trochanteric tenderness that is relieved by cles, and the most superior fibers are injection of a local anesthetic have TrPs more horizontal than are the underlying in the gluteus maximus instead of, or in gluteus medius fibers. The gluteus max- addition to, bursitis. Subacute trochan- imus rarely refers pain to the thigh, and teric bursitis has been commonly associ- then only for a few inches. The gluteus ated with low back pain, hip disease, and\/ medius may refer pain to midthigh, and or leg length discrepancies, which are the gluteus minimus commonly refers conditions that are often associated with pain that extends below the knee. myofascial TrPs of the gluteal muscula- ture. However, the location of the bursa is Except for the most anterior gluteus more lateral than the area where gluteus medius fibers (Fig. 7.2), TrP tenderness maximus TrPs are usually found. If pres- and taut bands palpated immediately be- ent, TrPs in this superficial muscle neath the skin in gluteal musculature be- should be detectable by their taut bands long to the gluteus maximus muscle. and local twitch responses. Other gluteal fibers must be palpated deep to at least one other layer of muscle. The gluteus maximus is one of the mus- cles attached to the sacrum that com- Tension of the gluteus maximus re- monly develops TrPs after sacroiliac joint stricts flexion at the hip; tension of the displacement.95 Recently Gitelman31 rein- other two gluteal muscles restricts adduc- forced this observation by noting that the tion. gluteus maximus often shows hypertonic- ity during sacroiliac fixation. This asym- As long as active gluteus maximus TrPs metrical tension with strong leverage on remain, the tenderness they refer may, on the sacrum would tend to maintain the examination, obscure detection of TrP in- sacral displacement until the gluteal ten- volvement in other gluteal muscles. sion was released. Swezey80 described pseudoradiculop- The pain referred by lumbar zygapo- athy in subacute trochanteric bursitis of physial (facet) joints is described and il- the subgluteus maximus bursa. The sub- lustrated in Chapter 3 on pages 25-26. gluteus maximus bursa lies deep to the converging fibers of the tensor fasciae Another disorder, fibrosis of the super- latae and the gluteus maximus muscles ficial lumbosacral fascia, was described where their fibers join to form the ilio- by Dittrich.14 The lumbar fascia serves as tibial tract. This bursa separates these the aponeurotic anchor for the latissimus converging fibers from the greater tro- dorsi and gluteus maximus muscles. The chanter and from the origin of the vastus cause of the fibrosis was believed to be lateralis muscle. Schapira and associ- tearing of the fascia due to excessive ates71 describe trochanteric bursitis as a muscular tension. The treatment recom- common clinical problem. Inflammation mended was resection of the connective of the trochanteric bursa produces intense tissue at the exact site of tenderness; ef- local pain with radiation to the lateral fectiveness of surgery was thought to be thigh area; pain sometimes extends ceph- due to denervation of the fascial struc- alad to the buttock and distally below the tures from which the pain arose. If this knee.80 It is aggravated by ambulatory ac- condition does in fact occur, it might be tivities and relieved by rest.71 Pain is also caused by the sustained tension placed caused by pressure applied over the bursa on the tendinous attachments of taut at the junction of the lower edge of the muscle fibers associated with myofascial greater trochanter and the shaft of the fe- TrPs. If so, inactivation of the TrPs might mur. In addition, pain is frequently elic- be a simpler and equally effective treat- ited by medial rotation and\/or abduction ment. at the hip; but there is no loss of hip mo- bility. Infiltration of the sensitive area","Chapter 7 \/ Gluteus Maximus Muscle 139 7. ACTIVATION AND PERPETUATION ing exercises (leg lifts) that hyperextend OF TRIGGER POINTS the low back and hip, either in the prone or standing position. Repetitious tasks, Activation such as frequently leaning over and lift- ing a baby out of the playpen, have been Myofascial TrPs in the gluteus maximus known to perpetuate gluteus maximus muscle are often activated by acute stress TrPs. overload during a fall or a near-fall. Acti- vation of TrPs is especially likely to occur Sitting too long in one position per- if the muscle sustains a vigorous length- petuates TrPs in this muscle, especially ening contraction in an effort to prevent when the individual is partially reclining the fall. The impact of a direct blow on with the knees straight, which com- one buttock, as in a backward fall onto a presses gluteus maximus TrPs and re- low wooden fence, has been responsible stricts circulation of blood in the muscle. for initiating gluteus maximus TrPs. The head-forward position with tho- Prolonged uphill walking while leaning racic kyphosis, in standing postures that forward can overload the gluteus max- increase hip flexion, is likely to overload imus. the gluteus maximus and perpetuate TrPs in it. Sleeping on one side with the thigh of the upper limb sharply flexed over the A short first metatarsal bone (Morton lower limb can overstretch the uppermost foot structure or Dudley J. Morton foot gluteus maximus muscle and activate its configuration)74 may perpetuate TrPs in TrPs. These active TrPs can induce re- the more horizontal fibers of the gluteus ferred pain that seriously disturbs sleep. maximus. This anatomical variant of foot On the other hand, sleeping on the back structure frequently induces medial rota- with the legs straight places the muscle in tion of the hip during the stance phase in the shortened position, which, if pro- walking, and this movement is counter- longed, also activates latent TrPs. Correc- acted to some extent by the horizontal fi- tive actions are discussed at the end of bers of the gluteus maximus. A corrective this chapter. pad placed in the shoe under the head of the short first metatarsal bone (described Another common, but avoidable, cause in Chapter 20) frequently corrects medial of activation of latent gluteal TrPs is the rotation and reduces overload irritation of injection of an irritant medication intra- TrPs in the lower posterior fibers of the muscularly into the gluteal area.86 As the gluteus maximus. most superficial gluteal muscle, the glu- teus maximus is the most likely to be in- Sitting on a wallet placed in a long hip jected. Persons giving such injections pocket that extends under the buttock can should palpate the muscles for TrPs and perpetuate and aggravate TrPs in the glu- avoid any tender spots. Diluting the mate- teal muscles by concentrating pressure on rial to be injected with an equal quantity them. The resultant low back and buttock of 2% procaine solution may prevent acti- pain is likely to be erroneously attributed vation of a latent TrP in the event that the to nerve pressure and has been called medication is accidentally injected into \\\"back pocket sciatica.\\\"33 However, pain the region of the TrP. referred from TrPs in the gluteus max- imus muscle alone would not have a full Perpetuation sciatic nerve distribution. Physical activities that can perpetuate Although a small hemipelvis does not gluteus maximus TrPs include swimming directly perpetuate gluteus maximus with the crawl stroke, which requires TrPs, the correction of this body asymme- hyperextension of the lumbar spine in ad- try to lighten the load on other muscles dition to hip extension. This forceful con- may aggravate and intensify the activity traction of the gluteus maximus and the of gluteus maximus TrPs. The seated pa- lower paraspinal extensors in a strongly tient may not tolerate the firmness of an shortened position can activate and per- ischial (\\\"butt\\\") lift placed on a chair seat petuate their TrPs. A similar cause of glu- under the muscle with TrPs. Patients teus maximus overload may be condition- with gluteus maximus TrPs usually want pressure distributed around the ischial","140 Part 1 \/ Lower Torso Pain tuberosity, not concentrated on it, which knee.39,46 When active TrPs are present in happens when a TrP or an area of referred the gluteus maximus muscle this test tenderness is compressed by the ischial characteristically reveals inconsistent lift. (ratchety) weakness (caused by inhibi- tion). If the patient with active TrPs in 8. PATIENT EXAMINATION this muscle exerts sufficient effort against fixed resistance in the shortened position, The examiner may obtain relevant infor- additional pain is likely to appear in the mation by observing the patient's seated muscle and in the reference zone. and ambulatory posture. Patients with ac- tive TrPs in the gluteus maximus muscle 9. TRIGGER POINT EXAMINATION are likely to walk with an antalgic gait (Figs. 7.3 and 7.4) marked by a brief single-limb support phase on the painful side with a corre- Taut bands in this superficial gluteal spondingly brief swing phase of the con- muscle are relatively easy to palpate, and tralateral limb. When seated, these pa- local twitch responses are vigorous and tients shift position frequently to relieve often visible. pressure on their gluteus maximus TrPs. The patient lies on the side with the Tightness of the gluteus maximus mus- muscle to be examined uppermost and cle is tested in the supine patient by with that thigh flexed sufficiently to take bringing the knee passively toward the up the slack. In some patients, a greater opposite axilla and medially rotating the degree of flexion (within the comfort thigh at the hip. Normally, the thigh zone) may increase the hypersensitivity should rest firmly against the chest at full of the TrPs to palpation. Both TrP1 and range of motion. Gluteus maximus TrPs TrP2 of the gluteus maximus muscle are can reduce this range by as much as 35\u00b0. best examined by flat palpation. The fin- ger is rubbed transversely across the fi- Palpation of the muscular attachments bers, which lie nearly parallel to the and bony prominences in the areas of re- dashed line in Figure 7.3. The padding ferred pain frequently reveals tenderness, placed under the hip in Figure 7.3 may be as pointed out by Kelly.43 The tenderness needed to relieve weight-bearing pressure along the musculotendinous junction, at on the bony prominences of the pelvis the origin of the gluteus maximus muscle and femur, especially when the patient below the iliac crest, may well be caused lies on a hard examining table. One lo- by the sustained tension produced by the cates TrP1 (cephalad X in Fig. 7.3) lateral taut bands associated with TrPs and may to the sacral attachment of the gluteus be referred tenderness from TrPs. maximus. Palpation of TrP2 is illustrated in Figure 7.3; this TrP usually is found Although the common standing test of slightly cephalad to the ischial tuberosity. trying to touch the fingers to the toes while bending forward with knees Examination for TrP3, in the lower bor- straight is usually interpreted as a test of der of the muscle, may be done by pincer hamstring tightness, tightness of the glu- palpation (Fig. 7.4) or by flat palpation teus maximus due to TrPs can also be re- against the ischium. One of this group of sponsible for limitation of this movement. TrPs is located in the most medial fibers A test that distinguishes between these of the gluteus maximus muscle and is ad- muscles is leaning forward with knees jacent to and closely associated with the bent while sitting in a chair; this move- vestigial coccygeal muscles described in ment is restricted by gluteus maximus Section 2. These gluteal fibers and the shortening, but not by hamstring muscle coccygeal muscle fibers both attach to the tension. coccyx and their TrPs refer pain to the coccyx. Examination sometimes distin- The strength of the gluteus maximus guishes between these muscles since the can be tested selectively by placing the gluteus maximus fibers course distally patient prone with the knee bent to mini- and laterally toward the fascia lata and mize hamstring action and having the pa- the posterior margin of the muscle often tient lift the knee up from the examining can be grasped between the fingers. table while a resisting force is applied downward on the back of the thigh at the","Chapter 7 \/ Gluteus Maximus Muscle 141 Figure 7.3. Flat palpation of a trigger point (TrP2) in of the ilium, and the dashed line locates the upper bor- der of the gluteus maximus muscle. The Xs mark the the right gluteus maximus muscle. The open circle two trigger-point areas not being palpated; TrP, is marks the greater trochanter. The solid circle covers most cephalad, and TrP3, most distal. the ischial tuberosity. The solid line identifies the crest 10. ENTRAPMENTS Recognition of associated TrPs in the gluteus medius and gluteus minimus No nerve entrapments due to myofascial muscles is important because tension TrPs in the gluteus maximus muscle have caused by these TrPs is not likely to be been identified. However, the middle released effectively by the stretch posi- cluneal nerves, which supply the skin tion used for the gluteus maximus mus- over the posterior portion of the gluteus cle. Myofascial TrPs in the lower lumbar maximus muscle, penetrate that muscle paraspinal muscles and in the hamstrings near its attachments along the crest of the distort pelvic mechanics and tend to ilium.22 The middle cluneal nerves, there- overload the gluteus maximus, thus inter- fore, could suffer entrapment by the taut fering with restoration of its normal func- bands of gluteus maximus TrPs. The up- tion and range of motion. per cluneal nerves avoid penetrating the muscle (and entrapment) by descending The antagonistic iliopsoas and rectus over the crest of the ilium; the lower femoris muscles may also develop TrPs cluneal nerves supply skin over the glu- that require treatment to achieve release teus maximus muscle by swinging around of gluteus maximus TrP tightness and to its lower border.13 attain full upright posture. 11. ASSOCIATED TRIGGER POINTS 12. INTERMITTENT COLD WITH STRETCH (Fig. 7.5) The posterior section of the gluteus Details concerning use of intermittent medius is the muscle most likely to de- cold with stretch for restoring full active velop TrPs in association with gluteus range of motion are found in Volume l 8 8 maximus TrPs. The posterior part of the for the stretch-and-spray technique and in gluteus minimus and the hamstring mus- Chapter 2 on page 9 of this volume for the cles on the same side are the next most application of ice instead of vapocoolant likely to become involved. Occasionally, spray. the lower ends of the long paraspinal muscles may develop secondary TrPs. A primary goal in the management of myofascial pain syndromes is teaching","142 Part 1 \/ Lower Torso Pain Figure 7.4. Examination by pincer palpation for trig- location of the more cephalad TrP, and the more lat- eral TrP2 in the gluteus maximus muscle. The solid ger points in the most medial fibers of the right gluteus line locates the crest of the ilium; the dashed line, the maximus muscle (TrP3 region). The TrP3 is being com- upper margin of the gluteus maximus muscle; and the pressed between the thumb and fingers and charac- open circle, the greater trochanter. teristically refers pain to the coccyx. The Xs mark the the patient that the pain and disability The jet stream of spray or the ice is ap- are of muscular origin. The patient is plied in slow parallel sweeps downward asked to note and compare the range of from the crest of the ilium and midline of motion before and after treatment. the sacrum to midthigh (Fig. 7.5A). As the When release of a tight gluteus max- muscle tension releases, the operator gen- imus is combined with release of the tly increases flexion at the hip to take up hamstrings (Chapter 16), the remarkable the slack, but is careful not to cause pain increase in range of hip flexion often and involuntary muscle contraction. The permits the patient, when sitting with thigh should ordinarily rest firmly against knees straight, to reach the toes, or to the chest when full stretch of the gluteus reach much closer to the toes than maximus has been achieved unless the before. The patient can readily feel the lower lumbar paraspinal muscles are also release of muscular tension and relate it involved. to the improvement in comfort and muscle function. Having achieved full release of the glu- teus maximus, the clinician applies moist For treatment by intermittent cold with heat over the buttock and the patient per- stretch, the relaxed patient lies on the forms several cycles of active range of mo- side opposite to the involved gluteus tion (full flexion and full extension of the maximus muscle. If the patient lies su- hip). pine, a significant part of the spray pat- tern over the muscle and zone of referred Alternative Methods pain (Fig. 7.5) cannot be covered by the vapocoolant. To start, the hip is flexed to Correction of ilial rotations and ilial the limit of comfort with the knee on the flares55 may be required before the hip treatment table. This position also can be taken into full flexion to release stretches tight piriformis and posterior the gluteus maximus TrPs. gluteus medius or minimus fibers, but in- completely. If these muscles are involved, By having the patient grasp the thigh the intermittent cold also should cover behind the knee and take up the slack the areas that correspond with their re- (Fig. 7.7), he or she gains experience in ferred pain patterns. passive self-stretch and can often judge better than the operator how much force to apply without causing pain. It is wise","Chapter 7 \/ Gluteus Maximus Muscle 143 Figure 7.5. Stretch position and the spray or ice-ap- the ilium, and the solid circle, the ischial tuberosity. On plication pattern (thin black lines and small arrows) for a hard examining table, a pad to soften the surface is three trigger points\u2014TrP1: TrP2, TrP3\u2014in the right glu- placed under the opposite greater trochanter. The teus maximus muscle. The Xs are positioned over the thick white arrows show the direction of pull by the op- three major TrP areas. The dashed line marks the up- erator. A, initial stretch position. 6, more advanced per border of the muscle. The open circle locates the stretch position. greater trochanter. The solid line marks the crest of to concentrate on releasing TrPi and TrP2 imus muscles by directing the ice or spray first; they are the ones most likely to cre- downward, starting at the lower thoracic ate confusion with the myofascial pain region, and then covering the length of picture caused by TrPs in other gluteal the buttock as the patient leans far for- muscles. ward. Relaxation can be enhanced by having the patient first inhale slowly An alternative stretch position is to while looking upward to encourage very have the patient seated as for a long para- gentle contraction and then exhale slowly spinal stretch with feet on the floor, lean- during the relaxation phase as the ice or ing forward with the arms hanging be- vapocoolant spray is applied. tween the knees (Volume l 9 3 ) . This posi- tion allows for release of tension in the Another method of treatment is post- lower paraspinal and the gluteus max- isometric relaxation of the gluteus max-","144 Part 1 \/ Lower Torso Pain imus, as described and illustrated by serted into the tender spot where the cli- Lewit.49 The patient lies prone; isometric nician feels the firm band; the resulting contraction is synchronized with inhala- twitch response can be felt between the tion and the relaxation phase is synchro- fingers. nized with exhalation. The clinician pal- pates the muscles bilaterally to ensure For all gluteus maximus TrPs, injection symmetrical and uniform contraction. is followed by passive stretch usually Lewit notes that for this muscle with this combined with ice or vapocoolant spray technique, no stretch of the muscle is re- application, and then by unhurried active quired; he notes also that this technique range of motion of the muscle through relieves tension in tender pelvic floor both the fully lengthened (thigh to chest) muscles. It is not clear whether the ten- and the fully shortened (thigh extended) sion being released is due to myofascial positions, at least two or three times. TrPs or is the result of articular dysfunc- Quick jerky movements should be tion. avoided. Finally, with the patient recum- bent in a relaxed, comfortable, warm situ- 13. INJECTION AND STRETCH ation, a moist heating pad or hot pack is (Fig. 7.6) applied to the buttock for 5 or 10 minutes to reduce postinjection soreness. Details of the injection-and-stretch tech- nique are presented on pages 74-86 in The patient should be warned of the Chapter 3 of Volume l.87 likelihood of postinjection soreness for a few days, following which, full benefit of After gluteus maximus TrPs have been the TrP injection should be realized. identified, their injection is relatively easy except in those patients with an ex- Fisk29 reported that 10% of his patients tremely thick padding of subcutaneous with low back pain demonstrated at least fat. For thin individuals, a 21- or 22- a 10\u00b0 restriction of straight leg raising on gauge, 37-mm (l1\/2-in) needle is sufficient, the painful side as measured by his \\\"Pas- but for some patients, a 21-gauge, 50-mm sive Hamstring Stretch Test.\\\" Palpation of (2-in) or longer needle may be necessary the gluteal musculature on the restricted to penetrate the subcutaneous fat and the side revealed trigger areas sufficiently full thickness of the gluteus maximus tender to cause the patient to respond muscle. with a \\\"jump sign.\\\" Application of thera- peutic pressure on these TrPs and their Gluteus maximus TrP1 (Fig. 7.6A) and injection with a local anesthetic im- TrP2 (Fig. 7.68) are each identified by flat proved the restricted hip flexion of his palpation and then are pinned down be- patients. tween the fingers of one hand so that the TrP can be impaled by the injection nee- 14. CORRECTIVE ACTIONS dle on the syringe held in the other hand. (Figs. 7.7 and 7.8) One expects to observe a local twitch re- sponse of the muscle and\/or a jump re- When patients present with chronic myo- sponse of the patient when the TrP is fascial pain syndromes characterized by penetrated by the needle. Frequently, proliferation of TrPs over a period of time multiple TrPs in an area require fanning and by poor or transient response to spe- of the needle with serial probing motions cific local therapy, perpetuating factors (Volume l 8 9 ) . Deep probing for TrP2 that should be thoroughly explored. Systemic extends too far laterally can reach the sci- perpetuating factors, as described in Vol- atic nerve and should be avoided. At the ume l , 9 2 may activate TrPs in any muscle, level of the gluteal fold, this large nerve including the gluteus maximus. Mechani- usually lies near the midpoint between cal perpetuating factors, in addition to the nearest palpable borders of the ischial those discussed below, are considered in tuberosity and the greater trochanter. Volume l.91 TrP3 is localized for injection by either Corrective Posture and Activities pincer palpation (Fig. 7.6C) or flat palpa- tion. When pincer palpation is used, the A lower limb-length discrepancy of 5 mm TrP is grasped firmly and the needle in- (1\/4 in) or more that causes a functional scoliosis in a patient with active gluteus","Chapter 7 \/ Gluteus Maximus Muscle 145 Figure 7.6. Injection of TrPs (Xs) in the right gluteus maximus muscle. The open circle marks the greater trochanter. The solid circle covers the ischial tuberosity. The solid line identifies the crest of the ilium, and the dashed line locates the upper border of the gluteus maximus muscle. A, injection of TrP1. B, injection of TrP2 directly against the side of the is- chial tuberosity. C, injection of TrP3 us- ing pincer palpation. maximus TrPs should be identified and both must usually be treated for lasting corrected, as described in Chapter 4, relief. pages 7 7 - 7 8 . When sacroiliac joint dis- placement and active TrPs of the gluteus Patients with active gluteus maximus maximus muscle are present together, TrPs should be taught to limit continuous sitting to 15 or 20 minutes and then to get","146 Part 1 \/ Lower Torso Pain Figure 7.7. Supine passive self-stretch of the right pressure on the knee joint. To complete the first phase gluteus maximus muscle (upper border outlined by of the Lewit technique, the subject uses the hands to dashed line) combined with the Lewit technique. Trig- resist a gentle voluntary effort by the lower limb mus- ger points in this muscle are marked by Xs. The open cles to extend the thigh at the hip. 8, to help achieve circle identifies the greater trochanter; the solid circle complete muscular relaxation during the second overlies the ischial tuberosity; and the solid line out- phase, a full breath is metered out slowly (small ar- lines the crest of the ilium. The arrows show the direc- rows) through pursed lips (avoiding any exhalation ef- tion of pull or push by the patient. The Lewit technique fort) as the patient relaxes the hip extensors and pas- has two phases. A, the individual first pulls the knee sively moves the thigh gently into further flexion to cephalad in order to flex the hip by grasping the distal take up the slack. This contract-relax-stretch se- thigh (not the leg). This hold avoids excessive flexion quence can be repeated. up and walk around before sitting again. cyx and sacrum just because that is where An interval timer placed across the room he or she feels the referred pain and ten- can remind the patient to get up, walk derness. across the room, turn off the timer, reset it, and return to the chair with minimal When the patient sleeps on the back, a distraction. roll or small pillow under the knees pre- vents full shortening of the gluteus max- A soft cushion with a hole in the center imus muscle. When side lying, a pillow (doughnut cushion) can be used to reduce should be placed between the knees to pre- sitting pressure on gluteal TrPs on one vent the uppermost thigh from assuming side by centering the hole under TrP2 or an excessively flexed and adducted posi- TrP3 of the affected muscle. The patient tion; such incorrect positioning can place should not center the hole under the coc- the affected gluteus maximus on painful,","Chapter 7 \/ Gluteus Maximus Muscle 147 Figure 7.8. Technique for passive self- stretch of the gluteus maximus and ham- string muscles and, if desired, the gas- trocnemius muscles in the seated posi- tion. Effectiveness of the stretch is en- hanced by use of postisometric relaxation as follows: A, while reaching forward as far as possible with only slight discomfort, the patient firmly grasps the legs or ankles. He or she simultaneously pushes the heels down against the floor and gently pulls upward against the legs with the hands (arrows). A few seconds of this isometric gluteus maximus con- traction is followed by relaxation that is enhanced by a full slow exhalation. Dur- ing this prolonged period of enhanced relaxation, the individual reaches for- ward to pick up any slack that has devel- oped, providing further lengthening of the muscles. With sufficient repetitions, the hands should reach the toes. 6, final position that includes the gastrocnemius passive stretch by pulling up on the feet. Then, the isometric contraction phase must include simultaneous voluntary ef- forts to push down with the knees and to gently plantar flex the feet at the ankles while using the hands to resist move- ment of the feet. sleep-disturbing stretch. For an illustration self-stretch is improved by using post- of proper positioning, see Figure 10.10. isometric relaxation,49 which is based on the hold-relax principle96 and is de- Hiking up steep hills, which involves scribed in detail in Chapter 2. The patient leaning forward at the hips, can overload should be encouraged to gain at least the muscle to exhaustion and should be some improvement in range of motion at limited. Leaning forward to paint a wall each treatment session until the thigh can or canvas while reaching with the paint be brought to the chest (with the knee brush can create a similar strain and near the opposite axilla) without pain. should be limited or avoided. The torso should be held erect and the knees bent, An alternative, seated technique for pas- if necessary. sive self-stretch of the gluteus maximus, which includes stretch of the hamstring Back-pocket sciatica33 is avoided by muscles, is illustrated and described in moving the wallet from the back pocket to Figure 7.8. This procedure can be modified a front pocket or a shoulder bag. to include gastrocnemius muscle self- stretch and can be combined to advantage The head-forward posture should be with the Lewit technique for enhancing re- corrected to establish an erect posture laxation of the affected muscles. that unloads the extensor muscles. See Chapter 28 for techniques to correct the During stretching of the gluteus max- head-forward posture. imus, the antagonistic rectus abdominis and iliopsoas muscles become unusually Corrective Exercises shortened. If these muscles harbor TrPs, they may suddenly cramp. This painful Patients with gluteus maximus TrPs are reactive cramping is relieved by stretch- routinely taught the gluteus maximus ing the antagonist iliopsoas and rectus passive self-stretch procedure, illustrated in Figure 7.7. The effectiveness of this","148 Part 1 \/ Lower Torso Pain abdominis muscles in turn, as illustrated 11. Ibid. (p. 500). in Figure 5.5, and in Volume l . 9 4 12. Ibid. (p. 566, Fig. 6 - 7 2 ) . 13. Ibid. (p. 1 2 3 6 ) . Many patients find self-treatment by is- chemic compression with a tennis ball 14. Dittrich RJ: Soft tissue lesions as cause of low useful for this muscle. The technique is back pain. Am J Surg 9 7 : 8 0 - 8 5 , 1 9 5 6 . similar to that illustrated in Figure 8.9 for the gluteus medius muscle. When a TrP 15. Duchenne GB: Physiology of Motion, translated by has been identified, the patient lies on a tennis ball to apply ischemic compres- E.B. Kaplan. J. B. Lippincott, Philadelphia, sion to the TrP; the tennis ball is placed on a hard surface like the floor or on a 1949. firm large book on the mattress. The prin- 16. Eisler P: Die Muskeln des Stammes. Gustav ciples of ischemic compression are de- scribed in Volume l . 9 0 Fischer, Jena, 1912 (pp. 451-455, Fig. 66). Patients may have been told always to 17. Ericson MO, Nisell R, Arborelius UP, et al.: Mus- bend at the knees, not at the waist,72 in or- cular activity during ergometer cycling. Scand J der to protect the back. That is good ad- Rehab Med 7 7 : 5 3 - 6 1 , 1985. vice to reduce pressure on the interverte- bral discs and to avoid overload of the 18. Ferner H, Staubesand J: Sobotta Atlas of Human paraspinal, quadratus lumborum, and Anatomy, Ed. 10, Vol. 2. Urban & Schwarzen- hamstring muscles. However, lifting by bending at the knees greatly increases the berg, Baltimore, 1983 (Figs. 7, 413). load on the gluteus maximus. Therefore, 19. Ibid. (p. 288). if TrPs in the gluteus maximus are caus- 20. Ibid. (Fig. 292). ing the pain and dysfunction, one should 21. Ibid. (Figs. 331 and 419). rise from stooping or rise from a chair by 22. Ibid. (Fig. 4 0 2 ) . placing one hand on the thigh, as illus- 23. Ibid. (Fig. 404). trated in Figure 22.16, to reduce the load 24. Ibid. (Fig. 4 0 6 ) . on the gluteus maximus. 25. Ibid. (Fig. 4 1 0 ) . 26. Ibid. (Fig. 4 1 2 ) . Although swimming is one of the best 27. Ibid. (Fig. 4 2 0 ) . forms of exercise, the crawl stroke and sometimes the breast stroke are likely to 28. Fischer FJ, Houtz SJ: Evaluation of the function aggravate TrPs in the gluteus maximus of the gluteus maximus muscle. Am J Phys Med muscle. The backstroke or sidestroke should replace the other strokes. 47:182-191, 1968. References 29. Fisk JW: The passive hamstring stretch test: clinical evaluation. NZ Med J 7 : 2 0 9 - 2 1 1 , 1979. 1. Anderson JE: Grant's Atlas of Anatomy, Ed. 8. Wil- liams & Wilkins, Baltimore, 1983 (Fig. 4-31). 30. Furlani J, Berzin F, Vitti M: Electromyographic study of the gluteus maximus muscle. Electromy- 2. Ibid. (Fig. 4 - 3 2 B ) . ogr Clin Neurophysiol 7 4 : 3 7 9 - 3 8 8 , 1974. 3. Ibid. (Fig. 3 - 5 7 ) . 4. Bardeen CR: The musculature, Sect. 5. In: Mor- 31. Gitelman R: A chiropractic approach to bio- ris's Human Anatomy, edited by C. M. Jackson, mechanical disorders of the lumbar spine and Ed. 6. Blakiston's Son & Co., Philadelphia, 1921. pelvis, Chapter 14. In Modern Developments in the 5. Basmajian JV, Deluca CJ: Muscles Alive, Ed. 5. Principles and Practice of Chiropractic, edited by S. Williams & Wilkins, Baltimore, 1985 (pp. 3 1 5 - 316, 380-381). Haldeman. Appleton-Century-Crofts, New York, 6. Bollet AJ: The relationship of the gluteus max- imus to intelligence. Medical Times 1 2 2 : 1 0 9 - 1 1 2 , 1980 (pp. 297-330, see p. 307). 1984. 7. Broer MR, Houtz SJ: Patterns of Muscular Activity 32. Good MG: Diagnosis and treatment of sciatic in Selected Sports Skills. Charles C Thomas, pain. Lancet 2 : 5 9 7 - 5 9 8 , 1942. Springfield, 1967. 8. Carter BL, Morehead J, Wolpert SM, et al.: Cross- 33. Gould N: Back-Pocket Sciatica. N Engl J Med Sectional Anatomy. Appleton-Century-Crofts, New York, 1977 (Sects. 37-43, 64). 290:633, 1974. 9. Clemente CD: Gray's Anatomy of the Human Body, 34. Greenlaw RK: Function of Muscles About the Hip American Ed. 30. Lea & Febiger, Philadelphia, 1985 (pp. 566-567). During Normal Level Walking. Queen's University, 10. Ibid. (p. 108, Fig. 3 - 4 2 ) . Kingston, Ontario, 1973 (thesis). 35. Gutstein M: Diagnosis and treatment of muscu- lar rheumatism. Br J Phys Med 7 : 3 0 2 - 3 2 1 , 1938. 36. Hollinshead WH: Anatomy for Surgeons, Ed. 3., Vol. 3, The Back and Limbs. Harper & Row, New York, 1982. 37. Hunter WS: Contributions of physical anthro- pology to understanding the aches and pains of aging. In Advances in Pain Research and Therapy, edited by J.J. Bonica and D. Albe-Fessard, Vol I, Raven Press, New York, 1976 (pp. 901-911). 38. Inman VT: Human locomotion. Can Med Assoc J 94:1047-1054, 1966. 39. Janda V: Muscle Function Testing. Butterworths, London, 1983 (p. 166). 40. Joseph J, Williams PL: Electromyography of cer- tain hip muscles. J Anat 9 \/ : 2 8 6 - 2 9 4 , 1957. 41. Joseph J: The pattern of activity of some muscles in women walking on high heels. Ann Phys Med 9:295-299, 1968. 42. Kamon E: Electromyographic kinesiology of jumping. Arch Phys Med Rehabil 5 2 : 1 5 2 - 1 5 7 , 1971.","Chapter 7 \/ Gluteus Maximus Muscle 149 43. Kelly M: Lumbago and abdominal pain. Med J 71. Schapira D, Nahir M, Scharf Y: Trochanteric Austral 7:311-317, 1942. bursitis: a common clinical problem. Arch Phys Med Rehabil 6 7 : 8 1 5 - 8 1 7 , 1 9 8 6 44. Kelly M: The nature of fibrositis. II. A study of 72. Sheon RP: A joint-protection guide for nonar- the causation of the myalgic lesion (rheumatic, ticular rheumatic disorders. Postgrad Med 77: traumatic, infective). Ann Rheum Dis 5 : 6 9 - 7 7 , 329-338, 1985. 1946. 73. Simons, DG: Myofascial pain syndromes, part of 45. Kelly M: Some rules for the employment of local Chapter 11. In Medical Rehabilitation, edited by analgesic in the treatment of somatic pain. Med J Austral 7 : 2 3 5 - 2 3 9 , 1947. J.V. Basmajian and R.L. Kirby. Williams & Wil- 46. Kendall FP, McCreary EK: Muscles, Testing and kins, Baltimore, 1984 (pp. 2 0 9 - 2 1 5 , 313-320). Function, Ed. 3. Williams & Wilkins, Baltimore, 74. Simons DG, Travell JG: Myofascial origins of 1983. low back pain. Parts 1,2,3. Postgrad Med 7 3 : 6 6 - 47. Lange M: Die Muskelharten (Myogelosen). J.F. 108, 1983. Lehmanns, Munchen, 1931 (pp. 32, 91, 106, 75. Simons DG, Travell JG: Myofascial pain syn- 137, 152). dromes, Chapter 25. In Textbook of Pain, edited 48. Lartschneider J: Die Steissbeinmuskulatur des by P.D. Wall and R. Melzack, Ed 2. Churchill Menschen und ihre Beziehungen zum M. leva- Livingstone, London, 1989 (pp. 368-385). tor ani und zur Beckenfascie. Denkschr K Akad d Wiss, Wein 62, 1895. 76. Sirca A, Susec-Michieli M: Selective type II fi- 49. Lewit K: Postisometric relaxation in combina- bre muscular atrophy in patients with osteoar- thritis of the hip. J Neurol Sci 4 4 : 1 4 9 - 1 5 9 , 1 9 8 0 . tion with other methods of muscular facilitation 77. Spalteholz W: Handatlas der Anatomie des Men- and inhibition. Manual Med 2 : 1 0 1 - 1 0 4 , 1 9 8 6 . schen, Ed. 11, Vol. 2. S. Hirzel, Leipzig, 1922 (p. 50. Lyons K, Perry J, Gronley JK, Barnes L, Anto- 357). nelli D: Timing and relative intensity of hip ex- 78. Stern JT: Anatomical and functional specializa- tions of the human gluteus maximus. Am J Phys tensor and abductor muscle action during level Anthrop 3 6 : 3 1 5 - 3 4 0 , 1 9 7 2 . and stair ambulation. Phys Ther 6 3 : 1 5 9 7 - 1 6 0 5 , 79. Swartout R, Compere EL: Ischiogluteal bursitis, 1983. the pain in the arse. JAMA 2 2 7 : 5 5 1 - 5 5 2 , 1 9 7 4 . 51. Markhede G, Stener B: Function after removal of 80. Swezey RL: Pseudo-radiculopathy in subacute various hip and thigh muscles for extirpation of trochanteric bursitis of the subgluteus maximus tumors. Acta Orthop Scand 5 2 : 3 7 3 - 3 9 5 , 1981. bursa. Arch Phys Med Rehabil 5 7 : 3 8 7 - 3 9 0 , 1 9 7 6 . 52. McMinn RMH, Hutchings RT: Color Atlas of 81. Tichy M, Grim M: Morphogenesis of the human Human Anatomy. Year Book Medical Publishers, gluteus maximus muscle arising from two mus- Chicago, 1977 (p. 245). cle primordia. Anat Embryol 173:275-277, 1 9 8 5 . 53. Ibid. (p. 292). 54. Ibid. (p. 295). 82. Tillmann B: Variations in the Pathway of the In- 55. Mitchell FL, Moran PS, Pruzzo NA: Evaluation ferior Gluteal Nerve. (Germ.) Anat Anz 7 4 5 : 2 9 3 - and Treatment Manual of Osteopathic Manipulative 302, 1979. Procedures. Mitchell, Moran & Pruzzo Associ- 83. Toldt C: An Atlas of Human Anatomy, translated by ates, Manchester, MO, 1979, (pp. 361-382). M.E. Paul, Ed. 2, Vol. 1. Macmillan, New York, 56. Nemeth G: On hip and lumbar biomechanics. A 1919 (p. 338). study of joint load and muscular activity. Scand 84. Ibid. (p. 288). J Rehabil Med (Supp.1) 10: 1 - 3 5 , 1984. 8 5 . Ibid. (p. 339). 57. Oddsson L, Thorstensson A: Fast voluntary 86. Travell J: Factors affecting pain of injection. JAMA 758:368-371, 1 9 5 5 . trunk flexion movements in standing: motor patterns. Acta Physiol Scand 729:93-106, 1987. 87. Travell JG, Simons DG: Myofascial Pain and Dys- function: The Trigger Point Manual. Williams & 58. Okada M: An electromyographic estimation of Wilkins, Baltimore, 1983. the relative muscular load in different human 88. Ibid. (Chapter 3, pp. 6 3 - 7 4 ) . postures. J Human Ergol 1 : 7 5 - 9 3 , 1972. 89. Ibid. (Chapter 3, pp. 8 4 - 8 5 , Fig. 3.12). 90. Ibid. (Chapter 3, pp. 8 6 - 8 7 ) . 59. Pauly JE: An electromyographic analysis of cer- 9 1 . Ibid. (Chapter 4, pp. 1 0 3 - 1 1 4 ) . 92. Ibid. (Chapter 4, pp. 1 1 4 - 1 5 6 ) . tain movements and exercises: 1. some deep 93. Ibid. (Chapter 4 8 , p. 6 4 8 , Fig. 4 8 . 6 A ) . muscles of the back. Anat Rec 1 5 5 : 2 2 3 - 2 3 4 , 94. Ibid. (Chapter 49, p. 6 7 6 , Fig. 49.6). 1966. 95. Travell J, Travell W: Therapy of low back pain 60. Pernkopf E: Atlas of Topographical and Applied by manipulation and of referred pain in the Human Anatomy, Vol. 2. W.B. Saunders, Philadel- lower extremity by procaine infiltration. Arch Phys Med 2 7 : 5 3 7 - 5 4 7 , 1 9 4 6 (see p. 540). phia, 1964 (Fig. 312). 96. Voss DE, Ionta MK, Myers BJ: Proprioceptive Neu- 61. Ibid. (Fig. 327). romuscular Facilitation: Patterns and Techniques, 62. Ibid. (Fig. 329). 63. Rasch PJ, Burke RK: Kinesiology and Applied Anat- Ed. 3. Harper & Row, Philadelphia, 1985 (pp. omy, Ed. 6. Lea & Febiger, Philadelphia, 1978 304-305). (pp. 273-274). 97. Weber EF: Ueber die Langenverhaltnisse der Fleischfasern der Muskeln in Allgemeinen. Ber- 64. Rohen JW, Yokochi C: Color Atlas of Anatomy, Ed. ichte uber die Verhandlungen der Koniglich Sachsis- chen Gesellschaft der Wissenschaften zu Leipzig 3: 2. Igaku-Shoin, New York, 1988 (p. 204). 65. Ibid. (p. 316). 63-86, 1851. 66. Ibid. (pp. 3 2 2 - 3 2 3 ) . 67. Ibid. (p. 328). 68. Ibid. (p. 418). 69. Ibid. (p. 4 1 9 ) . 70. Ibid. (pp. 440).","CHAPTER 8 Gluteus Medius Muscle \\\"Lumbago Muscle\\\" HIGHLIGHTS: The posterior portion of the glu- likely to produce detectable local twitch re- teus medius muscle lies deep to the gluteus max- sponses as are the anterior TrPs. Gluteus imus and its lower part covers the gluteus mini- medius ASSOCIATED TRIGGER POINTS may mus muscle. The gluteus medius is usually at occur as satellites to quadratus lumborum TrPs. least twice the weight of the gluteus minimus and INTERMITTENT COLD WITH STRETCH of TrPs is less than half as heavy as the gluteus max- in fibers of the anterior gluteus medius requires imus. Its myofascial trigger points (TrPs) cause extension and adduction of the thigh behind the REFERRED PAIN that is commonly identified as uninvolved lower limb. Posterior fibers are pas- low back pain or lumbago. Its three TrP regions sively lengthened by flexing and adducting the in- together refer pain and tenderness primarily volved thigh in front of the other lower limb. along the posterior crest of the ilium, to the sac- Sweeps of ice or vapocoolant spray extend from rum, and to the posterior and lateral aspects of the crest of the ilium over the sacrum and over the buttock. Pain and tenderness may extend to the buttock to midthigh. The release of tight ante- the upper thigh. Its ANATOMICAL ATTACH- rior and posterior fibers is followed by active MENTS are, proximally, along the anterior three- range of motion and moist heat. Ischemic com- fourths of the iliac crest and, distally, to the pression and deep massage provide helpful greater trochanter. INNERVATION is supplied manual therapy. When the INJECTION-AND- from spinal roots L4, L5, and S1, via the superior STRETCH technique is used, a local twitch may gluteal nerve. The main FUNCTION of this ab- be palpated, but is rarely seen when the needle ductor of the thigh is stabilization of the pelvis encounters the TrP. CORRECTIVE ACTIONS in- during single-limb stance. Myofascial TrPs in this clude sleeping on the uninvolved side with a pil- muscle cause SYMPTOMS of pain when walk- low between the knees, avoidance of prolonged ing, when lying on the back or on the affected immobility, use of the seated position when put- side, and when sitting slouched down in a chair. ting on pants, and appropriate placement of first Sacroiliac joint dysfunction is an important differ- metatarsal pads to correct for a Morton foot struc- ential diagnosis. PATIENT EXAMINATION should ture. Injection of irritating medications into TrPs include looking for the Morton foot structure, ob- should be avoided. The Abductor Self-stretch Ex- serving the patient's gait, and testing for re- ercise is recommended for a home program. stricted adduction of the thigh at the hip. TRIG- Home use of an exercise bicycle while in the GER POINT EXAMINATION is concentrated semireclining position provides a convenient and along and below the iliac crest. The muscle's an- comfortable conditioning activity. Self-adminis- terior and middle TrPs lie between skin and bone. tered ischemic compression is easily applied to The posterior TrP, region lies deep to the gluteus TrPs in either the anterior or posterior fibers while maximus muscle; TrPs in this region are not as the patient lies on a tennis ball. 1. REFERRED PAIN looked source of low back pain.56 Pain pro- (Fig. 8.1) jected from these TrPs is generally re- stricted to the immediate vicinity of the Myofascial trigger points (TrPs) in the glu- muscle. This nearby distribution is similar teus medius muscle are a commonly over- to the referral of pain from TrPs in the del- 150","Chapter 8 \/ Gluteus Medius Muscle 151 Figure 8.1. Pain patterns (bright red) referred from sacrum. The TrP2 area is located more cephalad and trigger points (TrPs) (Xs) in the right gluteus medius laterally, and refers pain caudally to the buttock and to muscle (darker red). The essential pain pattern is the upper thigh posteriorly and laterally. The most an- solid red, and the spillover pattern is stippled. The terior TrP3 occurs less often and refers pain bilaterally most medial TrP, refers pain primarily to the crest of over the sacrum and into the lowest lumbar region. the ilium, to the region of the sacroiliac joint, and to the toid muscle.74 Like the deltoid, the gluteus found in other parts of the gluteus medius medius also has three portions (posterior, muscle. middle, and anterior) where its TrPs are likely to be found. The region of gluteus Other authors illustrate4,28,60 or de- medius TrPa (Fig. 8.1) is close to the iliac scribe78 similar patterns of referred pain crest in the posterior portion of the muscle from this muscle. Two papers describe re- near the sacroiliac joint. TrP1 refers pain ferral of pain after injection of the gluteus and tenderness primarily along the poste- medius muscle with hypertonic sa- rior crest of the ilium, to the region of the line.29,63 Bates7 illustrates referral patterns sacroiliac joint, and over the sacrum on in children that are similar to the patterns the same side; pain may also extend over observed in adults. Sola60 describes glu- much of the buttock (Fig. 8.1, TrP1). teus medius referred pain as extending into the posterior thigh and calf; we be- The region where TrP2 is found (Fig. lieve this pattern of pain probably arises 8.1, TrP2) is also just below the iliac crest, from TrPs in the underlying gluteus mini- nearly centered along the length of the mus muscle (Chapter 9). H e 6 0 also notes crest. Pain referred from TrP2 is projected that the gluteus medius is a frequent more laterally and to the midgluteal re- cause of hip pain in the later stages of gion; it may extend into the upper thigh pregnancy. Kelly30 has also identified the posteriorly and laterally. gluteus medius as a likely source of lum- bago. Others23,31, 60 reported that it may The region of rarely seen TrP3 (Fig. 8.1, contribute to, or simulate, sciatica. TrP3) is likewise just below the iliac crest, but is near the anterior superior iliac spine. 2. ANATOMICAL ATTACHMENTS AND Pain from TrP3 is projected primarily along CONSIDERATIONS the iliac crest, over the lowest lumbar re- (Fig. 8.2) gion, and bilaterally over the sacrum. The thick, fan-shaped gluteus medius lies In previous publications, the individ- deep to the gluteus maximus muscle and ual pain patterns of these three TrPs (Fig. superficial to the gluteus minimus muscle 8.1) were consolidated into one compos- ite pattern.54,57, 6 6 , 6 8 Occasionally, TrPs are","152 Part 1 \/ Lower Torso Pain Gluteus medius Figure 8.2. Attachments of the right gluteus medius muscle (red) in the pos- terolateral view. The gluteus maximus muscle has been cut and removed; its distal end is reflected. Gluteus Gluteus maximus maximus (cut) Gluteus (cut) minimus on the outer surface of the pelvis. The cle from the surface of the greater tro- gluteus medius is attached proximally to chanter over which the tendon glides. the external surface of the ilium along the The bursa lies between the trochanteric anterior three-fourths of the iliac crest, attachments of the gluteus minimus prox- between the anterior and posterior gluteal imally and the gluteus medius distally, as lines,15 and to the gluteal aponeurosis illustrated in the Sobotta Atlas.16,19 that covers the anterolateral two-thirds of the muscle.1,10 The gluteus medius at- Autopsy samples58 of gluteus medius muscles taches distally to both sides of a broad in normal adults under age 44 years showed 58% tendon anchored to the posterosuperior slow-twitch type 1 fibers and 42% fast-twitch type angle and the external surface of the 2 muscle fibers. A relative (8%) loss of type 2 fi- greater trochanter5 (Fig. 8.2). As they ap- bers in the gluteus medius was observed in per- proach their femoral attachment, fiber sons with osteoarthritis of the hip. Another adult bundles of the superficial layer cross ob- group58 was divided equally between individuals liquely those of the deeper posterior por- older and younger than 65 years of age; although tion. The direction of the posterior fibers individual variability was great in both groups, in and the direction of the force that they ex- every subject the number of slow-twitch type 1 fi- ert are at right angles to the direction of bers, which depend largely on oxidative metabo- the most anterior fibers (Fig. 8.2). Occa- lism, exceeded the number of fast-twitch type 2 sionally, the gluteus medius is divided fibers, which utilize glycolytic energy pathways. into two distinct portions, or it may be fused with the piriformis muscle or with Supplemental References the gluteus minimus muscle.5 Other authors have illustrated the gluteus medius The trochanteric bursa of the gluteus as seen from behind: by itself,16,50 in relation to the medius separates the tendon of that mus- gluteus maximus,2,15,44,62,64 and in relation to the","Chapter 8 \/ Gluteus Medius Muscle 153 gluteus minimus. 19,44,51,65 It is also shown from in Duchenne12 found that stimulation of the anterior, front,18,61 in cross section,9,17 and in coronal sec- middle, or posterior portions of the gluteus tion.14,41 medius produced abduction at the hip. Stimula- tion of the anterior fibers first strongly rotated the Its attachments to the ilium and to the femur are thigh medially. Stimulation revealed that only a clearly illustrated,20, 4,0 49 as also is its extensive few posterior fibers produced weak lateral rota- proximal aponeurotic attachment.3,64 tion. 3. INNERVATION Greenlaw monitored the anterior and poste- rior fibers with fine-wire electrodes and found The gluteus medius muscle is innervated that both groups of fibers were active during by the inferior branch of the superior glu- medial (internal) rotation. The posterior fibers teal nerve, which passes between the glu- were not active during lateral (external) rota- teus medius and gluteus minimus, send- tion.22 Duchenne's report12 of weak lateral rota- ing branches to each muscle. The supe- tion by stimulation of selected posterior fibers is rior gluteal nerve carries fibers from the not altogether inconsistent with Greenlaw's re- fourth and fifth lumbar and the first sacral port, because Greenlaw may not have been moni- nerves.10,11 toring those fibers. Observation of a skeleton makes it clear that any gluteus medius fibers capa- 4. FUNCTION ble of producing lateral rotation of the thigh would be converted to medial rotators as the thigh The gluteus medius is the abductor moves from full extension toward flexion. chiefly responsible for stabilizing the pel- vis during single-limb weight bearing. The anterior fibers showed increasing EMG ac- During ambulation, the gluteus medius tivity as the degree of active flexion of the thigh and other abductors prevent the pelvis increased. These anterior fibers were also active from dropping excessively (tilting later- during straight leg raising or when sitting up from ally) toward the unsupported side. the supine position. Posterior fibers were inactive during flexion of the thigh and only minimally ac- Actions tive during an effort to maximally extend the thigh.22 The gluteus medius muscle is generally recognized as the most powerful abductor Functions of the thigh.6,10,25, 27, 46 The anterior fibers of this muscle also assist medial rotation of The primary function of the gluteus the thigh. The flexion and lateral rotation medius is to stabilize the pelvis during functions of this muscle are either mini- the single-limb stance phase of ambula- mal or are highly dependent on position- tion6,10 and thereby to prevent the contra- ing of the thigh.22 lateral side of the pelvis from dropping. This stabilization function requires about Inman26 reported that the gluteus medius usu- 10% of its maximum effort.26 The evolu- ally weighs about twice as much as the gluteus tion of this muscle from a propulsive minimus, which, in turn, is nearly twice as large muscle to a stabilizing one is well de- as the only other major abductor at the hip, the scribed and illustrated.37 tensor fasciae latae. Weber76 found the gluteus medius to be more than four times as heavy as the Using fine-wire electrodes in the ante- gluteus minimus. rior and in the posterior portions of the muscle during slow and fast ambulation, Anatomically, the two-layer overlap arrange- Greenlaw22 found that the two portions of ment of the gluteus medius (Fig. 8.2) should im- the muscle had similar activity patterns at prove the effectiveness of the posterior fibers in both speeds. Lyons and co-workers39 also producing lateral rotation and the anterior fibers found that activity was greatest immedi- in producing medial rotation, as compared with ately before and through the first half of the simple fan arrangement of the gluteus mini- stance phase on the same side. Activity mus fibers (Fig. 9.3). then faded out until a brief burst ap- peared with toe-off; another brief burst Electromyographic (EMG) studies6,22,26,39,77 have anticipated heel-strike. The posterior por- confirmed the observations of Duchenne12 and the tion of the muscle showed considerably conclusion of anatomists5, 10, 62 that the gluteus medius is primarily an abductor of the thigh.","154 Part 1 \/ Lower Torso Pain less activity than the anterior portion dur- 6. SYMPTOMS ing all phases of ambulation.22 Patients with active gluteus medius TrPs The normal \\\"fan\\\" sign of the gluteus medius is are likely to complain of pain on walking, observed as a more rapid ebbing of electrical ac- especially if they have an uncorrected tivity in the posterior fibers as compared to the Morton foot structure (Chapter 20, Sec- anterior fibers during the stance phase of free tions 7 and 8). walking.53,59 This sign was lost in patients with se- vere osteoarthritis of the hip53 and reflects the dis- Patients with gluteus medius TrPs have tortion of normal sequencing of fiber activity due difficulty sleeping on the affected side. to joint dysfunction. To avoid this pressure on the TrPs, they sleep on the back or on the other side. At times, differences in the onset, duration, and However, lying on the back may painfully degree of EMG activity appeared among the ante- compress posterior gluteus medius TrPs. rior, middle, and posterior fibers of this muscle When lying on the side opposite to the during activities of walking, crawling, stair as- gluteus medius TrPs, a pillow should be cending and descending, shoe tying, sitting, and placed between the knees to prevent ex- single-limb standing while leaning forward. This cessive adduction that painfully stretches independence of activity justifies a three-segment taut bands in the muscle. The best sleep- conceptual model of this muscle.59 ing position may be half-supine, that is, turned halfway between lying on the un- Electrical activity of the gluteus medius was in- affected side and on the back, with the creased during ergometer cycling when the work- torso supported by a pillow. load, pedalling rate, or saddle height was in- creased and when the posterior foot position on Patients with active gluteus medius the pedal was used.13 TrPs are also uncomfortable when sitting in a slumped position, rolled back on the As expected, carrying a load in the ipsilateral buttocks so that body weight compresses hand reduces activity of the gluteus medius mus- these TrPs. cle, and carrying the load on the opposite side in- creases its activity.45 Ghori and Luckwill found Differential Diagnosis that walking with a load of 20% of body weight in the contralateral hand or on the back significantly Although the referred pain patterns from prolonged EMG activity of the gluteus medius gluteus maximus and gluteus medius TrPs muscle.21 overlap, it is essential to distinguish be- tween them for therapy that employs In only one of seven subjects was the gluteus stretch. Tightness of the gluteus maximus medius more than minimally active when the sub- due to TrPs restricts flexion at the hip; ject lifted a 12.8-kg box from the floor in three dif- tightness of the gluteus medius restricts ferent ways.43 Therefore TrPs in this muscle adduction. Careful attention to the loca- should not usually compromise lifting. tion of the TrPs in the buttock, as well as to restriction of motion, helps establish Loss of strength due to surgical removal of the their identification [see Section 9, Fig. gluteus medius and gluteus minimus muscles was 8.5). In the anterior superior portion of reported42 in one case when the only abductor re- the buttock, only the gluteus medius mus- maining was the sartorius muscle and, in another cle lies between the skin and the ilium.44 case, when only the abducting part of the gluteus Elsewhere in the buttock, the gluteus maximus remained. In both cases, nearly half of maximus is the superficial muscle; the maximal abduction strength was retained, but gluteus medius lies deep to it. without endurance.42 These gluteal muscles are essential for endurance and full strength. Therapeutically, distinguishing be- tween gluteus medius and gluteus minimus 5. FUNCTIONAL (MYOTATIC) UNIT TrPs is less critical, except for the extent of the spray pattern or the depth of needle The muscles that assist the abduction penetration required for TrP injection. function of the gluteus medius are the Anatomically44 and functionally, these gluteus minimus, tensor fasciae latae, two muscles are hard to differentiate; and, to a lesser extent, the sartorius, piri- however, a pain reference zone extending formis,24 and part of the gluteus max- over the full length of the thigh, and imus42 muscle. Janda27 also includes the sometimes as far as the ankle, clearly iliopsoas muscle as assisting abduction.","Chapter 8 \/ Gluteus Medius Muscle 155 identifies gluteus minimus TrPs. The sion of the aorta, common iliac, or hypo- TrPs of the piriformis muscle are not likely gastric (internal iliac) artery could have to cause low back pain over the sacrum, TrPs in the gluteus medius and tensor fas- but they do refer pain over the buttock ciae latae muscles. When TrPs were pres- and sometimes into the thigh posteriorly. ent, ischemia caused pain in their refer- ence zones. In some of the patients, walk- Reynolds48 reminds us that the pain re- ing tolerance was related more to the ferred from gluteus medius TrPs may be severity of myalgic spots (TrPs) than to confusingly like the pain originating from the decrease in blood flow. sacroiliac joint dysfunction and disease. The diagnosis of sacroiliac joint locking Vascular occlusion is identified by de- and its management by manipulation has creased pulses, impaired skin circulation, been described with detailed case re- and by ultrasound or contrast dye studies. ports75 and is reviewed in Chapter 2. This On the other hand, TrPs are identified by dysfunction is more likely to be associ- their specific referred pain patterns and ated with gluteus minimus TrPs than by restricted range of motion of the af- with gluteus medius TrPs, but should be fected muscles; palpation of the muscles considered.75 reveals spot tenderness in taut bands and may elicit a local twitch response. Re- Lumbar facet joints can refer pain to ferred pain that appears in predictable the buttock region that may be mistaken patterns is evoked by pressure on the ten- for gluteal TrPs. The recognition of this der spot, a TrP. articular source of referred pain is re- viewed in Chapter 3, pages 25-26. 7. ACTIVATION AND PERPETUATION OF TRIGGER POINTS Inflammation of the subgluteus medius (Fig. 8.3) bursa at the greater trochanter can be a cause of pain and tenderness in the region Events and activities likely to initiate of the greater trochanter.52 This pain must TrPs in the gluteus medius muscle in- be distinguished from pain referred by clude sudden falls, sports injuries, run- gluteus medius TrPs. This tenderness ning, lengthy tennis matches, aerobics, must be distinguished from musculoten- long walks on a soft sandy beach, weight dinous tenderness at the greater trochan- bearing on only one limb for an extended teric attachment of taut bands associated period of time, and injection of medica- with gluteus medius TrPs. This distinc- tions into the muscle. Such injections tion can be made by examining for the may activate latent TrPs.67 Injection of ir- TrPs. ritating medications in the immediate vi- cinity of latent or active TrPs enhances Chronic pain following spinal surgery their activity and can cause severe re- for low back pain is not uncommon. It ferred pain.67 may be due to overlooked TrPs and it can then be resolved by identifying the re- Sola60 identifies a discrepancy of at sponsible TrPs and managing them ap- least 1 cm in leg length as a cause of uni- propriately. Another source of pain is the lateral low back pain and of TrPs in the postmyelogram or postoperative compli- gluteus medius muscle. Pelvic distortion cation, arachnoiditis or arachnoradicu- can produce an apparent lower limb- litis. One important part of an effective length discrepancy [see Chapter 4, Sec- management program for this condition is tion 8 for more on this important issue). inactivation of TrPs in the gluteal mus- cles and in other muscles in the regions The long second (short first) metatarsal that are involved.47 of the Morton foot structure, which is de- scribed in detail in Chapter 20, Sections 7 Since the pain of intermittent claudica- and 8, commonly perpetuates and can ac- tion is related to muscular activity, the tivate TrPs in the gluteus medius muscle. patient's history may not clearly distin- The abnormal weight distribution on the guish between pain of vascular origin and foot usually causes excessive pronation, pain of myofascial TrP origin. Arcangeli as illustrated in Figure 8.36. The resul- and associates4 emphasized that the pain tant medial rotation and adduction of the of claudication often was similar in char- thigh at the hip tend to overload the glu- acter to that referred from TrPs. They noted that patients with stenosis or occlu-","156 Part 1 \/ Lower Torso Pain Figure 8.3. Strain of the right gluteus medius muscle adduction and medial rotation of the thigh at the hip. during ambulation caused by the relatively long sec- C, patient's attempt to relieve the resultant gluteal ond and short first metatarsal bones of the Morton foot muscle strain by laterally rotating and abducting the structure. A, ambulation with normal foot alignment, lower limb at the hip and by further everting the foot to not out-toeing. B, pronation of the right foot as the ball provide a more balanced two-point support on the first of the foot rocks inward and weight bearing pro- and second metatarsal heads at toe-off. This reduction gresses from the heel to the knife-edge of the protrud- of medial rotation and adduction at the hip minimizes ing head of the long second metatarsal bone at toe-off. the compensatory strain of hip abductors, chiefly the This produces the appearance of genu valgum with gluteus medius muscle. teus medius and vastus medialis muscles. flexed, or sitting with the seat bottom in- Rocking of the foot laterally during ambu- clined backward and thus flexing the lation often overloads the peroneal mus- thighs acutely at the hip. cles. Some individuals compensate by lat- erally rotating the thigh and further evert- Although a head-forward kyphotic pos- ing the foot (Fig. 8.3C), which imposes ture is more likely to perpetuate gluteus additional stress on the foot itself but is maximus TrPs, it can be a significant fac- less stressful on the gluteus medius mus- tor in the perpetuation of gluteus medius cle. TrPs. Displacement of the articular surfaces Sitting on a credit-card-filled wallet of the sacroiliac joint can help perpetuate placed in a deep hip pocket can concen- gluteus medius TrPs and, if present, trate pressure on gluteus medius TrPs in- should be corrected for lasting response ducing referred pain from them, produc- to therapy.75 ing a form of \\\"credit-card-wallet\\\" sciat- ica.38 Established active or latent TrPs in the gluteus medius muscle are aggravated by 8. PATIENT EXAMINATION prolonged flexion at the hip, as when sleeping in the fetal position, sitting in a If the pain distribution suggests gluteus low chair with feet on the floor and knees medius TrPs, the patient's gait should be","Chapter 8 \/ Gluteus Medius Muscle 157 Figure 8.4. Palpation of the posterior trigger point cle; and the dashed line identifies the upper (anterior) (TrP1) in the right gluteus medius muscle. The open border of the gluteus maximus, which also approxi- circle locates the greater trochanter; the solid line mates the direction of the gluteus medius fibers at this marks the crest of the ilium (also the upper margin of TrP. Palpation is performed with the tip of the examin- the gluteus medius); the doffed line delineates the up- ing digit moved perpendicularly to the dashed line. per and posterior borders of the gluteus minimus mus- observed for the distortions illustrated in on the uninvolved side as described pre- Figure 8.3 and the feet should be exam- viously, but with the uppermost thigh ex- ined for the long second metatarsal bone tended as illustrated by Kendall and Mc- (see Chapter 20, Section 8). The examiner Creary.32 Moderate and ratchety or may observe that the patient stands with \\\"break-away\\\" weakness is likely, as com- the weight predominantly on one leg in pared to the uninvolved side. order to relieve tension caused by a lower limb-length inequality or to relieve dis- With the patient lying supine on the ex- comfort caused by posterior ilial torsion amining table, lateral rotation of the lower of the pelvis with displacement of the limb on the affected side may be caused by sacroiliac joint on the opposite side. The shortening due to TrPs in one or all of the patient should be examined for other evi- following: the posterior part of the gluteus dence of lower limb-length discrepancy; medius and gluteus minimus muscles, see Volume l 7 0 and Section 8 of Chapter 4 the piriformis, and the gemelli-obturator- in this volume. The senior author de- quadratus femoris group of muscles. In the scribed examination and treatment for sa- supine position, the lower limb on the croiliac joint displacement.75 side of a posterior ilial torsion is rotated outward, if nothing else complicates the During the examination for evidence of situation. shortening of the gluteus medius muscle because of TrPs, the patient lies on the 9. TRIGGER POINT EXAMINATION uninvolved side and the uppermost thigh (Figs. 8.4 and 8.5) is flexed to 90\u00b0; normally, the knee should drop onto the examining table. Failure of All TrPs in the gluteus medius muscle are the knee to reach the table indicates re- examined while the patient lies on the striction of hip adduction that may be side opposite to the affected muscle. Fig- caused by TrP tension in the gluteus ure 8.4 illustrates the examination by flat medius muscle and also by increased ten- palpation of TrP1, which has the most sion in the fascia lata. posterior location of gluteus medius TrPs. A pillow placed between the knees helps During the examination for weakness of prevent painful stretch of exquisitely sen- this muscle due to TrPs, the patient lies sitive TrPs in this muscle. The same pa-","158 Part 1 \/ Lower Torso Pain tient position is used for examination of maximus covers much of the posterior the more anterior TrP2 and TrP3, which portion of the gluteus medius, and the are marked by Xs in Figure 8.4. The latter gluteus minimus lies deep to the distal two TrPs are covered only by skin and two-thirds of the gluteus medius. subcutaneous tissue. To find the taut bands of TrP2 and TrP3, the muscle fibers 10. ENTRAPMENTS are rolled against the underlying bone by rubbing the examining fingertip across the No nerve entrapment by the gluteus fibers (perpendicular to fiber direction), medius muscle has been identified. using the deep tissue technique of mov- ing the skin with the fingertip. Local 11. ASSOCIATED TRIGGER POINTS twitch responses elicited in the posterior and distal parts of the gluteus medius When the posterior fibers of the gluteus muscle are rarely visible through the medius harbor TrPs, secondary TrPs are overlying gluteus maximus, but may be likely to develop in the piriformis and detected by palpation with the fingers of posterior part of the gluteus minimus, the other hand. which are closely related functionally, and sometimes in the gluteus maximus Sola60 points out that, with extensive muscle. When the anterior fibers of the involvement, gluteus medius fibers along gluteus medius are involved, the tensor the entire gluteal ridge from the sacroiliac fasciae latae, as part of that functional joint to the anterior superior iliac spine unit, may also develop secondary TrPs. may contain painful TrPs. The gluteus medius commonly devel- Deep gluteus maximus TrPs may be dif- ops satellite TrPs in response to active ficult to distinguish from gluteus medius quadratus lumborum TrPs, because the TrPi, where the two muscles have similar gluteus medius lies in the pain reference fiber directions.44 Taut bands in the su- zone of that muscle. This relationship can perficial fibers of the gluteus maximus be so close that pressure on quadratus clearly feel as if they are just under the lumborum TrPs induces not only referred skin. Taut bands that feel deeper may be pain over the posterior gluteus medius in deeper gluteus maximus fibers or in muscle (referral pattern of quadratus lum- underlying muscle. If TrPs are found in borum TrPs), but also referred pain that the gluteus maximus, additional deeper extends over the upper thigh (gluteus TrPs may not be distinguishable until the medius TrP referred pain pattern) as well. overlying TrPs have been inactivated. Pressure on the satellite TrP in the glu- One should apply therapy for TrPs in teus medius induces pain only in its char- both muscles when in doubt as to which acteristic reference zone. Inactivation of is involved. only this satellite gluteal TrP usually pro- vides merely temporary relief. On the All three of the common gluteus other hand, inactivation of the quadratus medius TrPs are located cephalad to the lumborum TrPs may eliminate the glu- gluteus minimus muscle (Fig. 8.4). Thus, teus medius satellite TrPs as well. In location of the TrP, as well as extensive- other cases, both the quadratus lumborum ness of the pain pattern, helps distinguish TrPs and their satellite TrPs in the gluteus gluteus medius TrPs from gluteus mini- medius must be inactivated individually mus TrPs. for complete lasting relief. In order to identify by palpation the Furthermore, Sola60 reports the reverse muscle in which a TrP lies, a schematic situation, that gluteus medius TrPs can drawing showing the limits of each mus- induce TrPs in the quadratus lumborum cle and where the gluteal muscles overlap muscle. He notes that these gluteal TrPs is helpful (Fig. 8.5A). The gluteus medius may also interact with muscles in the cer- is limited superiorly by the rim of the pel- vical area and thus contribute to cervical vis, in front by a line from slightly behind pain and headache. We suggest that a the anterior superior iliac spine to the mechanism for this interaction may be a greater trochanter, and below (posteri- postural compensation for tilted pelvic orly) by the piriformis line (Fig. 8.56), and shoulder-girdle axes that are caused which runs along the upper border of the by weak gluteal function. Sola60 states piriformis muscle (Fig. 8.5A). The gluteus","r Chapter 8 \/ Gluteus Medius Muscle 159 Gluteus maximus, medius, and minimus Iliac crest Gluteus medius Tensor fasciae latae, Gluteus proximal attachment maximus and medius Anterior superior iliac spine Sacrum Gluteus medius and minimus Gluteus Gluteus maximus minimus and Piriformis line piriformis Greater trochanter Gluteus maximus Figure 8.5. Schematic drawing that shows overlap the gluteus minimus. Dark red shows where three of gluteal and piriformis muscles from a slightly poste- muscle layers\u2014gluteus maximus, gluteus medius, and rior, nearly lateral view. A, light red identifies the areas gluteus minimus\u2014are present. Note that the upper where only a single gluteal muscle may be palpated, border of the piriformis corresponds closely with the except for the anterior part of the gluteus minimus that lower borders of the gluteus medius and gluteus mini- is covered also by the tensor fasciae latae muscle (the mus muscles. The gluteus medius sometimes over- iliac attachment is marked by hatched line and is la- laps the piriformis. B, the piriformis line that corre- beled). In these single-muscle areas, there is little like- sponds closely to the upper border of the piriformis lihood of encountering misleading tenderness from an- muscle runs from the proximal end of the greater tro- other gluteal muscle or from the piriformis muscle. Me- chanter (open square) to the upper end of the palpa- dium red on the left side of A illustrates where either ble free border of the sacrum where it joins the ilium the gluteus medius or piriformis may be palpated (open circle). The piriformis line is divided into thirds through the gluteus maximus in an area free of deeper for convenience in locating TrPs in the posterior part of gluteus minimus sensitivity; medium red on the right the gluteus minimus and in the piriformis muscle. side of A illustrates where the gluteus medius overlies that the gluteus medius seldom causes 12. INTERMITTENT COLD WITH pain as a single muscle syndrome, but STRETCH usually is involved with other muscles as (Fig. 8.6) part of a functional unit. Details of intermittent cold with stretch Posterior ilial torsion is commonly as- appear in Volume 1, pages 63-74 for the sociated with shortening and TrP activity stretch-and-spray technique and in Chap- of the posterior part of the gluteus medius ter 2 on page 9 of this volume for the ap- muscle and of the parallel piriformis. The plication of ice instead of vapocoolant. patient is unlikely to experience pro- longed relief unless TrPs in both the glu- To restore full, active range of motion teus medius and piriformis muscles are that is restricted because of active TrPs in inactivated and the ilial torsion is cor- the gluteus medius muscle, the sequence rected. of intermittent cold with stretch is ap-","160 Part 1 \/ Lower Torso Pain Figure 8.6. Stretch position and intermittent cold eased over the edge of the examining table and al- pattern (thin arrows) for TrPs in the right gluteus lowed to drop toward the floor gently. The force of medius muscle. The solid line marks the crest of the gravity gradually enhances the stretch into adduction. ilium. The open circle marks the greater trochanter. S, intermittent cold with stretch of the posterior fibers The large arrows show the direction of passive move- (TrP, and TrP2). While applying the vapocoolant spray ment required to lengthen the muscle. A, intermittent or ice, the operator's hand brings the thigh forward to cold with stretch of the anterior fibers (TrP3). To about 30\u00b0 of flexion at the hip. As parallel sweeps of lengthen the muscle passively, the operator lifts the the cold release muscle tightness, the operator lowers thigh backward toward extension so that it can be the limb to adduct the thigh (large curved arrow). plied with the patient lying comfortably The intermittent cold is applied to nearly on the uninvolved side. A small pillow or the same area of skin for treatment of ei- towel roll may be needed under the pa- ther anterior or posterior gluteus medius tient's waist for positioning the lumbar TrPs (Fig. 8.6A and 8 ) . spine, or under the lower hip for comfort. For gluteus medius TrPs, parallel sweeps When releasing tension of anterior of ice or vapocoolant spray are applied in gluteus medius fibers, the operator one direction distalward over the muscle should also apply ice or spray to the and over its referred pain pattern fol- skin over the tensor fasciae latae muscle. lowed by gentle passive stretch (Fig 8.6). To stretch the anterior section of the glu- teus medius (or minimus), after several","Chapter 8 \/ Gluteus Medius Muscle 161 sweeps of ice or spray, the thigh should is applied promptly over the area of the be extended and then adducted, as TrP and its major pain pattern. shown in Figure 8.6A Taut bands with TrPs in the tensor fasciae latae muscle When releasing either anterior or poste- also restrict extension and adduction; rior gluteus medius fibers by intermittent lateral rotation should be added to the cold with stretch, it is important to pre- extension and adduction for a complete vent reactive cramping (TrP kickback) by stretch of the tensor fasciae latae (see stretching antagonists that harbor TrPs. Chapter 12). Caution: this maneuver can This precaution applies to the gluteus overstress the sacroiliac joint if done too maximus and hamstring muscles as an- vigorously or held too long. tagonists for anterior gluteus medius TrPs and to the adductor group of muscles as In this region, as in all regions of the antagonists for posterior gluteus medius body, treatment by lengthening to the full TrPs. range of motion is not attempted if the pa- tient is hypermobile in joints involved in Active TrPs, especially those in the the stretch procedure (see page 18 in more anterior, superficial fibers of the glu- Chapter 2 regarding hypermobility). teus medius muscle, are also responsive When this problem is encountered, one to deep massage and to ischemic com- can effectively treat the muscle non-inva- pression, which can be applied directly sively by using either ischemic compres- with the thumbs. sion or stripping massage for local stretching of the taut band (see page 9 in When gluteus medius TrPs have not Chapter 2). been completely inactivated by intermit- tent cold with stretch and these other mo- When applying intermittent cold for dalities, the patient may be able to in- posterior gluteus medius TrPs, the crease the level of functional activity by sweeps should also cover the skin over wrapping an elastic bandage or sacroiliac the piriformis muscle. To lengthen the (pelvic) belt firmly around the pelvis over posterior fibers of the gluteus medius (or the anterior gluteal and hip musculature. minimus) to full range of motion, the In principle, the effect of this technique thigh is flexed to approximately 30\u00b0 and may be analogous to the reflex effect of then adducted (Fig. 8.6B). In this posi- pinching the skin over the sternocleido- tion, medial or lateral rotation has little mastoid muscle.8,72 effect on stretch of the posterior fibers. 13. INJECTION AND STRETCH Thigh flexion to 90\u00b0 significantly alters (Fig. 8.7) the function of posterior fibers in the glu- teus medius muscle. In this position, For injection, as for intermittent cold muscle length is changed very little by with stretch, the patient lies on the unin- adduction, but posterior gluteus medius volved side. The taut band is located and and minimus fibers are stretched by lat- the spot tenderness of the posterior TrP1 eral rotation. For practical purposes, how- is positioned between the fingers (Fig. ever, that movement is often blocked by 8.7A). The probing needle is inserted di- other soft tissues, including the articular rectly toward the region of deep tender- capsule. The most effective stretch of ness. It is sometimes possible to detect by these fibers is achieved by adduction of palpation a local twitch response through the thigh at 30\u00b0 of flexion. the overlying thick gluteus maximus mus- cle. Alternative body positioning for pas- sive stretch is presented in Chapter 9 (Fig. Similarly, the more anterior TrP2 (Fig. 9.6). A passive stretch technique using 8.78) and TrP3 (Fig. 8.7C) are injected as postisometric relaxation with the patient shown. The clinician is likely to feel a lo- supine is described and illustrated by cal twitch response when the needle pen- Lewit34 and described in Chapter 2 of this etrates one of these TrPs. Since the most volume. visible twitch tends to occur at the distal end of the gluteus medius fibers where Following release of TrP tension, the they lie under the gluteus maximus mus- patient actively moves the limb slowly cle, the response is rarely seen. The pa- through full adduction and abduction range of motion several times. Moist heat","162 Part 1 \/ Lower Torso Pain Figure 8.7. Injection of TrPs (Xs) in the posterior, middle, and anterior portions (TrP1, TrP2, TrP3, respectively) of the right gluteus medius muscle. The solid line locates the crest of the ilium. The dashed line shows the anterior border of the gluteus maximus, and the dotted line delineates the upper and posterior bor- ders of the gluteus minimus muscle. The open circle marks the greater trochan- ter. A, injection of TrP1. S, injection of TrP2. C, injection of TrP3. tient may or may not be aware of a twitch. If these muscle-lengthening and TrP in- Application of intermittent cold with jection approaches produce only tempo- stretch of the involved muscle follows rary results, one should examine for over- TrP injection. The limb is then actively looked TrPs in functionally related mus- moved through full range of motion sev- cles and also evaluate perpetuating eral times, and moist heat is applied over factors (See Section 7 of this chapter and the injected muscle. Volume l69).","Chapter 8 \/ Gluteus Medius Muscle 163 14. CORRECTIVE ACTIONS (Figs. 8.8-8.10) Body Mechanics For gluteus medius TrPs that were acti- vated or perpetuated by a Morton foot structure, the shoe should be corrected temporarily by inserting a first metatarsal pad. Installation of a wedge (Chapter 20, Section 14) in the sole of the shoe pro- vides a more permanent correction. This wedge is known as a \\\"Flying Dutchman.\\\" Posture and Activities (Fig. 8.8) When a person who is prone to gluteus Figure 8.8. Safe and unsafe dressing positions. A, medius TrPs sleeps on the side, a pillow safe position, seated. The individual can also lean should be placed between the knees, as il- against a wall to provide body support and avoid the lustrated for the quadratus lumborum necessity of balancing on one lower limb. B, hazard- muscle in Figure 4.31. ous way (red X) balancing on one foot, leaning forward and sideways, and overloading the gluteal muscles on One should avoid sitting too long in the weight-bearing side. This position also runs the any one position. When driving a car, use risk of catching the foot in the clothing, thereby sud- of a cruise control permits more freedom denly straining the muscles to maintain balance and of movement. At home, use of a rocking avoid falling. chair reduces immobility and encourages muscular relaxation. One should avoid pated for taut bands and tender spots that placing a wallet full of credit cards in a are likely to be TrPs, so that those loca- deep hip pocket.38 tions can be avoided.67 The medication can be diluted with sufficient 2% pro- Individuals prone to gluteal TrPs should not cross the legs when sitting; this position shortens the anterior gluteus medius fibers on the uppermost side and often compresses the peroneal nerve against the knee underneath. Some indi- viduals tend to cross the lower limbs in lieu of using an appropriate ischial lift to correct a small hemipelvis; they should learn to use an ischial (\\\"butt\\\") lift in- stead, as described in Volume l . 7 1 Individuals should be warned to sit (Fig. 8.8A) or lean against a wall while putting on pants or socks; they should never put them on while standing up without additional support (Fig. 8.8B). If the person catches a foot in the pants and loses balance, sudden acute overload of the gluteal muscles is likely to activate TrPs, even though the person does not fall. When giving intramuscular medication in the gluteal area, it is necessary to avoid TrPs that might be activated by the in- jected solution. The muscle is first pal-","164 Part 1 \/ Lower Torso Pain Figure 8.9. Ischemic compression ap- plied to the gluteus medius and gluteus minimus TrPs using a tennis ball tor self- administered therapy. A padded book or board is required when the patient lies on a soft compressible surface. The solid circle locates the anterior superior iliac spine; the solid line, the crest of the ilium; the dashed line, the anterior bor- der of the gluteus maximus muscle; and the open circle, the greater trochanter. A, tennis ball placed under TrPs in the midportion of the gluteus medius and gluteus minimus muscles. B, pressure applied to TrPs in the anterior part of the gluteus medius and gluteus minimus muscles by rolling the body weight onto the ball. caine to make the injected solution 0.5% tors; relaxation during slow exhalation procaine. The addition of procaine greatly permits enhancement of the force of grav- reduces the chance of activating a latent ity to take up any slack that develops. TrP, should it be exposed accidentally to Self-stretch of anterior gluteus medius fi- the medication. bers is performed in the position of Figure 8.6A. Corrective Exercises (Figs. 8.9 and 8.10) The patient may be taught to lie on a tennis ball, as illustrated in Figure 8.9A to The patient should perform postisometric inactivate TrPs in the middle fibers, and relaxation36 and synchronous respira- in Figure 8.96 for TrPs in the anterior fi- tion35 (Chapter 2) as part of the Abductor bers of the gluteus medius muscle. The Self-stretch Exercise for the middle and tennis ball technique is described in Vol- posterior fibers of the gluteus medius. ume l.73 Effectiveness of this treatment is This technique employs the stretch posi- increased when the patient rolls the ball tion of Figure 8.66 and has also been de- along the taut band over the TrP, as de- scribed and illustrated for this muscle by scribed in Section 14, Chapter 9 of this Lewit.34 To lengthen the muscle, the side- volume. lying patient places the involved limb in adduction in front of the other limb with If the abductors remain weak following the knee straight and with the thigh in ap- inactivation of their TrPs, they can be proximately 30\u00b0 of flexion at the hip; the safely strengthened first under supervi- patient stabilizes the pelvis by holding sion and then at home. In order to use a onto the edge of the table. Then the pa- lengthening contraction and to avoid a tient performs slow inhalation, which in- shortening contraction of the gluteus duces a gentle contraction of the abduc- medius at this stage, the patient lies on the uninvolved side and first elevates the involved lower limb (with the knee and","Chapter 8 \/ Gluteus Medius Muscle 165 Figure 8.10. Outline drawing of bicycle exercise per- justed to the comfort of the individual patient. This ar- formed in the semireclining position using a patio rangement practically eliminates back and gluteal recliner with the leg-rest portion folded back. The an- muscle overload while it improves venous return from gle of the back support (amount of hip flexion) is ad- the lower limbs. hip straight) in \\\"false\\\" abduction (thigh 3. Ibid. (Fig. 4 - 3 8 ) . laterally rotated). The elevation move- 4. Arcangeli P, Digiesi V, Ronchi O, et al.: Mecha- ment in this position activates primarily the thigh flexors. The patient then medi- nisms of ischemic pain in peripheral occlusive ally rotates the thigh to the neutral posi- arterial disease. In Advances in Pain Research and tion (true abduction) and lowers the limb, Therapy, edited by J. J. Bonica and D. Albe-Fes- using both the tensor fasciae latae and the gluteal muscles in lengthening contrac- sard, Vol. 1. Raven Press, New York, 1976 (pp. tions, resisting gravity. These motions are described and illustrated by Lewit.33 965-973). 5. Bardeen CR: The musculature, Sect. 5. In Mor- Use of an exercise bicycle at home helps to recondition muscles suffering ris's Human Anatomy, edited by C. M. Jackson, from disuse. However, the upright seated position may aggravate gluteus medius Ed. 6. Blakiston's Son & Co., Philadelphia, 1921. TrPs. Positioning the bicycle to allow the 6. Basmajian JV, Deluca CJ: Muscles Alive, Ed. 5. patient to reach the pedals from behind it, while partially reclining with the lower Williams & Wilkins, Baltimore, 1985 (pp. 258, limbs horizontal, can avoid overloading the gluteus medius and postural trunk 316-317). muscles (Fig. 8.10). To accomplish this, a low chair or folding lounge chair is 7. Bates T, Grunwaldt E: Myofascial pain in child- placed behind the bicycle with the chair hood. J Pediatr 5 3 : 1 9 8 - 2 0 9 , 1 9 5 8 . seat at the level of the pedals. Pillows or cushions are added, as needed, to support 8. Brody SI: Sore throat of myofascial origin. Milit the patient's back at a comfortable angle. Med ? 2 9 : 9 - 1 9 , 1964. Frequent moderate exercise for short peri- ods is more effective than infrequent peri- 9. Carter BL, Morehead J, Wolpert SM, et al.: Cross- ods of strenuous exercise. A controlled Sectional Anatomy. Appleton-Century-Crofts, New slowly incremented program permits steady progress with minimum likelihood York, 1977 (Sects. 35-41, 44-46). of overload and relapse. 10. Clemente CD: Gray's Anatomy of the Human Body, References American Ed. 30. Lea & Febiger, Philadelphia, 1. Anderson JE: Grant's Atlas of Anatomy, Ed. 8. Wil- 1985 (pp. 567-568). liams & Wilkins, Baltimore, 1983 (Fig. 4-24). 11. Ibid. (p. 1236) 12. Duchenne GB: Physiology of Motion, translated by 2. Ibid. (Fig. 4 - 3 1 ) . E.B. Kaplan. J. B. Lippincott, Philadelphia, 1949 (pp.249-252, 254). 13. Ericson MO, Nisell R, Arborelius UP, et al.: Mus- cular activity during ergometer cycling. Scand J Rehabil Med 17:53-61, 1 9 8 5 . 14. Ferner H, Staubesand J: Sobotta Atlas of Human Anatomy, Ed. 10, Vol. 2. Urban & Schwarzen- berg, Baltimore, 1983 (Fig. 152). 15. Ibid. (Figs. 331, 403). 16. Ibid. (Fig. 4 0 6 ) . 17. Ibid. (Fig. 4 1 0 ) . 18. Ibid. (Figs. 4 1 5 - 4 1 7 ) . 19. Ibid. (Figs. 4 1 8 , 419). 20. Ibid. (Fig. 4 2 0 ) . 21. Ghori GMU, Luckwill RG: Responses of the lower limb to load carrying in walking man. Eur J Appl Physiol 5 4 : 1 4 5 - 1 5 0 , 1 9 8 5 .","166 Part 1 \/ Lower Torso Pain 22. Greenlaw RK: Function of Muscles About the Hip 4 6 . Rasch PJ, Burke RK: Kinesiology and Applied Anat- During Normal Level Walking. Queen's University, omy, Ed. 6. Lea & Febiger, Philadelphia, 1978 Kingston, Ontario, 1973 (thesis) (pp. 87-89, (pp. 275-276). 47. Rask MR: Postoperative arachnoradiculitis. J 132-134, 157, 191). Neurol Orthop Surg 7 : 1 5 7 - 1 6 6 , 1980. 23. Gutstein-Good M: Idiopathic myalgia simulating visceral and other diseases. Lancet 2 : 3 2 6 - 3 2 8 , 48. Reynolds MD: Myofascial trigger point syn- dromes in the practice of rheumatology. Arch 1940 (p. 328, case 6). Phys Med Rehabil 6 2 : 1 1 1 - 1 1 4 , 1981. 24. Hollinshead WH: Functional Anatomy of the Limbs 4 9 . Rohen JW, Yokochi C: Color Atlas of Anatomy, Ed. and Back, Ed. 4. W.B. Saunders, Philadelphia, 2. Igaku-Shoin, New York, 1988 (p. 418). 1976 (pp. 297-298, Fig. 18-2). 50. Ibid. (pp. 4 1 8 - 4 1 9 ) . 2 5 . Hollinshead WH: Anatomy for Surgeons, Ed. 3., 5 1 . Ibid. (p. 441). Vol. 3, The Back and Limbs. Harper & Row, New 52. Schapira D, Nahir M, Scharf Y: Trochanteric bursitis: a common clinical problem. Arch Phys York, 1982 (pp. 664-666). Med Rehabil 6 7 : 8 1 5 - 8 1 7 , 1986. 26. Inman VT: Functional aspects of the abductor 53. Schenkel C: Das Fachersymptom des M. muscles of the hip. J Bone Joint Surg 2 9 : 6 0 7 - 6 1 9 , glutaeus medius bei Hufttotalendoprothesen. Z 1947 (Fig. 4, p. 610). Orthop 110: 3 6 3 - 3 6 7 , 1972. 27. Janda V: Muscle Function Testing. Butterworths, 54. Simons, DG: Myofascial pain syndromes, Part of London, 1983 (p.172). Chapter 11. In Medical Rehabilitation, edited by 28. Kellgren JH: A preliminary account of referred J.V. Basmajian and R.L. Kirby. Williams & Wil- pains arising from muscle. Br Med J 1:325-327, kins, Baltimore, 1984 (pp. 209-215, 313-320). 1938 (see p. 327). 55. Simons DG: Myofascial pain syndrome due to 29. Kellgren JH: Observations on referred pain aris- trigger points, Chapter 4 5 . In Rehabilitation Medi- ing from muscle. Clin Sci 3 : 1 7 5 - 1 9 0 , 1938 (pp. cine edited by Joseph Goodgold. C. V. Mosby 176, 177, Fig. 1). Co., St. Louis, 1988 (pp. 686-723). 30. Kelly M: Lumbago and abdominal pain. Med J 56. Simons DG, Travell JG: Myofascial origins of Austral 7 : 3 1 1 - 3 1 7 , 1942 (p. 313). low back pain. 3. Pelvic and lower extremity 31. Kelly M: Some rules for the employment of local muscles. Postgrad Med 7 3 : 9 9 - 1 0 8 , 1983. analgesic in the treatment of somatic pain. Med J Austral 7 : 2 3 5 - 2 3 9 , 1947. 57. Simons DG, Travell JG: Myofascial pain syn- dromes, Chapter 2 5 . In Textbook of Pain edited by 32. Kendall FP, McCreary EK: Muscles, Testing and Function, Ed. 3. Williams & Wilkins, Baltimore, P.D. Wall and R. Melzack, Ed. 2. Churchill Liv- 1983 (p. 169). ingstone, London, 1989 (pp. 368-385). 33. Lewit K: Manipulative Therapy in Rehabilitation of 58. Sirca A, Susec-Michieli M: Selective type II fi- the Motor System. Butterworths, London, 1985 bre muscular atrophy in patients with osteoar- (p. 148, Fig. 4.36, p. 285). thritis of the hip. J Neurol Sci 4 4 : 1 4 9 - 1 5 9 , 1980. 34. Ibid, (p.281, Fig. 6.101b). 59. Soderberg GL, Dostal WF: Electromyographic 35. Lewit K: Postisometric relaxation in combina- study of three parts of the gluteus medius mus- tion with other methods of muscular facilitation cle during functional activities. Phys Ther 58: and inhibition. Manual Med 7 : 1 0 1 - 1 0 4 , 1986. 691-696, 1978. 36. Lewit K, Simons DG: Myofascial pain: relief by post-isometric relaxation. Arch Phys Med Rehabil 60. Sola AE: Trigger point therapy, Chapter 47. In Clinical Procedures in Emergency Medicine, edited 65:452-456, 1984. 37. Lovejoy CO: Evolution of human walking. Sci by J.R. Roberts and J.R. Hedges. W.B. Saunders, Philadelphia, 1985 (pp. 6 7 4 - 6 8 6 , see p. 683). Am 259:118-125, (November) 1988. 6 1 . Spalteholz W: Handatlas der Anatomie des Men- 38. Lutz EG: Credit-card-wallet sciatica. JAMA 240: schen, Ed. 11, Vol. 2. S. Hirzel, Leipzig, 1922 (p. 738, 1978. 350, Fig. 428). 62. Ibid. (p. 358, Fig. 4 3 6 ) . 39. Lyons K, Perry J, Gronley JK, et al.: Timing and 63. Steinbrocker O, Isenberg SA, Silver M, et al.: Ob- relative intensity of hip extensor and abductor servations on pain produced by injection of hy- muscle action during level and stair ambulation. Phys Ther 6 3 : 1 5 9 7 - 1 6 0 5 , 1983. pertonic saline into muscles and other support- 4 0 . McMinn RMH, Hutchings RT: Color Atlas of ive tissues. J Clin Invest 3 2 : 1 0 4 5 - 1 0 5 1 , 1953. Human Anatomy. Year Book Medical Publishers, 64. Toldt C: An Atlas of Human Anatomy, translated by Chicago, 1977 (pp. 264, 273, 274). M.E. Paul, Ed. 2, Vol. 1. Macmillan, New York, 4 1 . Ibid. (p. 302). 1919 (p. 340). 42. Markhiede G, Stener B: Function after removal of 6 5 . Ibid. (p. 341). various hip and thigh muscles for extirpation of 66. Travell J: Basis for the multiple uses of local tumors. Acfa Orthop Scand 5 2 : 3 7 3 - 3 9 5 , 1981. block of somatic trigger areas (procaine infiltra- 43. Nemeth G, Ekholm J, Aborelius UP: Hip load tion and ethyl chloride spray). Miss Valley Med J moments and muscular activity during lifting. 77:13-22, 1949 (see pp. 19-20). Scand J Rehab Med 16: 1 0 3 - 1 1 1 , 1984. 4 4 . Netter FH: The Ciba Collection of Medical Illustra- 67. Travell J: Factors affecting pain of injection. tions, Vol.8, Musculoskeletal System. Part I: JAMA 7 5 8 : 3 6 8 - 3 7 1 , 1 9 5 5 . Anatomy, Physiology and Metabolic Disorders. 68. Travell J, Rinzler SH: The myofascial genesis of pain. Postgrad Med 7 7 : 4 2 5 - 4 3 4 , 1952. Ciba-Geigy Corporation, Summit, 1987 (p.85). 69. Travell JG, Simons DG: Myofascial Pain and Dys- 45. Neumann DA, Cook TM: Effect of load and car- function: The Trigger Point Manual. Williams & rying position on the electromyographic activity Wilkins, Baltimore, 1983 (pp. 103-164). 70. Ibid. (pp. 1 0 4 - 1 1 0 , 6 5 1 - 6 5 3 ) . of the gluteus medius muscle during walking. Phys Ther 6 5 : 3 0 5 - 3 1 1 , 1 9 8 5 .","Chapter 8 \/ Gluteus Medius Muscle 167 71. Ibid. (pp.\u00a0109\u2010110,\u00a0651\u2010653).\u00a0 Fleischfasern\u00a0 der\u00a0 Muskeln\u00a0 in\u00a0 Allgemeinen.\u00a0 Ber-ichte 72. Ibid. (p.\u00a0209).\u00a0 uber die Verhandlungen der Kdniglich Sachsis-chen 73. Ibid. (p.\u00a0386)\u00a0 74. Ibid. (p.\u00a0432).\u00a0 Gesellschaft der Wissenschaften zu Leipzig 3: 63\u201086,\u00a0 75. Travell\u00a0 J,\u00a0 Travell\u00a0 W:\u00a0 Therapy\u00a0 of\u00a0 low\u00a0 back\u00a0 pain\u00a0 by\u00a0 1851.\u00a0 77. Wilson\u00a0 GL,\u00a0 Capen\u00a0 EK,\u00a0 Stubbs\u00a0 NB:\u00a0 A\u00a0 fine\u2010wire\u00a0 manipulation\u00a0 and\u00a0 of\u00a0 referred\u00a0 pain\u00a0 in\u00a0 the\u00a0 lower\u00a0 electrode\u00a0 investigation\u00a0 of\u00a0 the\u00a0 gluteus\u00a0 minimus\u00a0 and\u00a0 extremity\u00a0 by\u00a0 procaine\u00a0 infiltration.\u00a0 Arch Phys Med 27:537\u2010547,\u00a01946\u00a0(pp.\u00a0544\u2010545).\u00a0 gluteus\u00a0medius\u00a0muscles.\u00a0Res 0\u00a0 Am Assoc Health Phys 76. Weber\u00a0EF:\u00a0Ueber\u00a0die\u00a0Langenverhaltnisse\u00a0der\u00a0 Educ 47:824\u2010828,\u00a01976.\u00a0 \u00a0 78. Winter\u00a0 Z:\u00a0 Referred\u00a0 pain\u00a0 in\u00a0 fibrositis.\u00a0 Med Rec 157:34-37, 1944.\u00a0","CHAPTER 9 Gluteus Minimus Muscle \\\"Pseudo-Sciatica\\\" HIGHLIGHTS: The REFERRED PAIN from trig- gluteus minimus is palpated for spot tenderness ger points (TrPs) in the anterior part of the glu- deep to the tensor fasciae latae muscle. To lo- teus minimus muscle extends over the lower lat- cate TrPs in the posterior fibers, the line corre- eral buttock, down the lateral aspect of the thigh, sponding to the lower border of the gluteus mini- knee, and leg to the ankle. The TrPs in the pos- mus is identified and the region above this line terior fibers of this muscle have a similar but explored for localized deep tenderness. The cli- more posterior pattern that projects pain over nician should consider ASSOCIATED TRIGGER the lower medial aspect of the buttock, and POINTS in the quadratus lumborum as perpetu- down the back of the thigh and calf. The ANA- ators of satellite gluteus minimus TrPs. To apply TOMICAL ATTACHMENTS of the gluteus mini- INTERMITTENT COLD WITH STRETCH to this mus are similar to, but less extensive in length muscle, the involved (uppermost) thigh of the than, those of the overlying gluteus medius. The side-lying patient is adducted over the side or primary FUNCTION of this abductor of the thigh end of the examining table and the intermittent is to help keep the pelvis level during single-limb cold is applied over the muscle fibers and their weight bearing. The TrPs in this muscle cause referred pain zones. Added extension empha- SYMPTOMS of pain in a characteristic pattern, sizes lengthening of anterior fibers, and flexion especially when arising from a chair or when to 30\u00b0 emphasizes lengthening of posterior walking. To distinguish these symptoms from fibers. The INJECTION-AND-STRETCH ap- similar ones caused by radiculopathy, the re- proach first requires localization of the focal ten- sponsible TrPs must be positively identified. AC- derness characteristic of TrPs in the tight mus- TIVATION of TrPs in the gluteus minimus can be cle. Useful CORRECTIVE ACTIONS include caused by acute or chronic overload, by dis- loss of excessive body weight, keeping the body placement of the sacroiliac joint, and by nerve warm, changing hip position frequently, appro- root irritation. They may be perpetuated by priate body positioning at night, correction of sa- these factors and also by prolonged immobility croiliac joint displacement, avoidance of strenu- or by sitting on a wallet in the back pocket. The ous unaccustomed physical activities, and position for TRIGGER POINT EXAMINATION is avoidance of the injection of medications into side lying on the unaffected side. To locate TrPs the muscle. A home self-stretch program should in the anterior fibers of this muscle, the borders be established for most patients with this myo- of the tensor fasciae latae muscle are identified fascial pain syndrome. distal to the anterior superior iliac spine. The 1. REFERRED PAIN muscle that its true origin is easily over- (Figs. 9.1 and 9.2) looked. Pain referred from gluteus minimus TrPs Travell, in 1946, first distinguished can be intolerably persistent and excruci- the pain patterns of TrPs in the anterior atingly severe. The TrP source of the pain and posterior portions of the gluteus is so deep in the gluteal musculature and minimus muscle. These portions refer much of the pain is so remote from the pain down the lateral and posterior as- pects of the lower limb, respectively.56 168","Chapter 9 \/ Gluteus Minimus Muscle 169 Figure 9.1. Pattern of referred pain from trigger Figure 9.2. Composite pain pattern (bright red) re- points (TrPs) (Xs) in the anterior portion of the right ferred from TrPs (Xs) in the posterior part of the right gluteus minimus muscle (light red). The essential pain gluteus minimus muscle (darker red). The essential pattern is solid red and the spillover extension found pain pattern is solid red and the spillover pattern is when the muscle is more severely involved is stippled. stippled. The large X marks the most common loca- tion of TrPs in the posterior part of this muscle. The These patterns, unlike those of the two most anterior small X lies at the junction of the anterior more superficial gluteal muscles, may and posterior portions of this muscle. extend to the ankle, as also reported subsequently.43-47,53,54,61 that covers the posterior aspect of the thigh and calf. This referred pattern of The TrPs in the anterior portion of the pain sometimes includes the back of the gluteus minimus project both pain and knee. Referral of tenderness to the gluteal tenderness (Fig. 9.1) to the lower lateral portion of this pain pattern may account part of the buttock, the lateral aspect of for the diffuse tenderness of the gluteus the thigh and knee, and to the peroneal maximus muscle that is observed in many region of the leg as far as the ankle. Ordi- patients with posterior gluteus minimus narily, gluteus minimus referred pain TrPs. does not extend beyond the ankle.56 Rarely, however, it may include the dor- Good18 described pain in the sciatic dis- sum of the foot.53 tribution as commonly arising from ten- der spots in gluteal muscles, without Myofascial TrPs located in the posterior specifying which muscle. Kellgren24 part of the gluteus minimus muscle refer found that in 55 of 70 patients seen for pain and tenderness (Fig. 9.2) in a pattern \\\"sciatica\\\" the pain was of ligamentous or that includes most of the buttock (concen- muscular origin, commonly from the glu- trating on its lower medial aspect), and teal musculature.","170 Part 1 \/ Lower Torso Pain Gluteus medius Figure 9.3. Attachments of the right gluteus minimus muscle (red) in the pos- terolateral view. To a large extent, the overlying gluteus maximus and gluteus medius muscles have been removed. Gluteus Gluteus maximus minimus Gluteus Greater medius sciatic notch Gluteus maximus 2. ANATOMICAL ATTACHMENTS AND the tensor fasciae latae are shown in the CONSIDERATIONS serial cross sections of Figure 9.4. The (Figs. 9.3 and 9.4) greater thickness of the anterior part of the gluteus minimus, as compared with The gluteus minimus, the deepest of the its posterior part, is not generally appre- three gluteal muscles, is also the small- ciated. This difference in thickness is est in length and lightest in weight.58 Its seen in the lowest section of Figure 9.4, fan shape conforms closely to the over- the plane of which lies approximately lying gluteus medius (Fig. 9.3). Proxi- midway between the anterior superior mally, its fibers attach to the pelvis iliac spine and the anterior inferior iliac along the outer surface of the ilium be- spine. That cross section also illustrates tween the anterior and inferior glu- how one can palpate the anterior part of teal lines. This attachment closely ap- the gluteus minimus both behind the proaches the greater sciatic foramen posterior margin of the tensor fasciae (Fig. 9.3) through which the piriformis latae and between the tensor's anterior muscle exits the p e l v i s 5 0 (see Fig. 10.2). margin and the anterior border of the il- Distally, the fibers of the gluteus mini- ium. mus converge onto its tendon, which attaches to the femur at the upper- The trochanteric bursa of the gluteus most part of the anterior surface of the minimus, which lies between the anterior greater trochanter,8,22 deep and anterior part of the muscle's tendon and the to the attachment of the piriformis mus- greater trochanter, facilitates gliding move- cle.30,31,50 ment of the tendon over the trochanter.8,22 This gliding movement of the tendon is The relative thickness of the gluteus necessary for the anterior fibers of the minimus and its anatomical relation to muscle to reach full stretch range of mo- tion.","Chapter 9 \/ Gluteus Minimus Muscle 171 Pelvic viscera Rectus abdominis Internal oblique L5-S1 disc Transversus Lumbar nerve V abdominis External oblique Sacral nerve I Colon Cauda equina Gluteus minimus Spinous process lliacus ofL, Psoas major Multifidi and iliocostalis lumborum Gluteus medius Subcutaneous fat Anterior superior iliac spine Iliopsoas Gluteus minimus Sacral vertebra I Gluteus medius Sacral nerve I L5-S1 disc Gluteus maximus Subcutaneous fat Cauda equina Iliopsoas Tensor fasciae latae Multifidi and iliocostalis Gluteus minimus lumborum Gluteus medius External iliac Ilium artery and vein Gluteus maximus Internal iliac Subcutaneous fat artery and vein Sacroiliac joint Retroperitoneal fat Piriformis Sacrum Multifidi and iliocostalis lumborum Figure 9.4. Serial cross sections through the pelvis rior superior iliac spine and the anterior inferior iliac that show the gluteus minimus muscle (dark red). The spine. At the latter level, the thickest part of the ante- three sections show the relation of the anterior portion rior portion of the gluteus minimus muscle may be of this muscle to the ilium, to neighboring muscles subcutaneous between the tensor fasciae latae and (light red) and to the skin. The level of the middle sec- the gluteus medius muscles. This anterior portion is tion passes through the anterior superior iliac spine. palpated for TrPs along the posterior margin of and The plane of the lowest section lies between the ante- deep to the tensor fasciae latae muscle.","172 Part 1 \/ Lower Torso Pain Supplemental References sidered much more effective in producing medial rotation of the thigh than the pos- The entire gluteus minimus muscle is presented terior fibers are in producing lateral rota- in serial cross sections.7 Frontal sections through tion.522 This conclusion is reinforced by the hip joint show the relation of the distal por- examination of an articulated skeleton tion of this muscle to the other two gluteal mus- and noting the location of the muscle's at- cles.12 tachments. Just below the level of the anterior inferior iliac Functions spine, tenderness in the anterior gluteus minimus can be palpated only by exerting deep pressure The functions of the gluteus minimus are between the tensor fasciae latae muscle on one usually lumped with those of the gluteus side and the rectus femoris tendon and sartorius medius. Authors generally agree that all muscle on the other. A section through, and per- of the gluteus minimus fibers assist the pendicular to, the axis of the neck of the femur14,36 gluteus medius muscle in its stabilizing shows why. function of maintaining the pelvis level during ambulation.5,8, 2 0 . 3 7 It thus helps The gluteus minimus and piriformis muscles prevent the pelvis from dropping exces- are seen from behind,1,15,49,50 with vascular sup- sively (tilting laterally) toward the unsup- ply,13 and in relation to the other two gluteal mus- ported side. cles.34 Seen from the side,3 the thick anterior por- tion of the gluteus minimus is readily apparent. Duchenne10 identified no subject in whom the Seen from in front,51 the potential for palpating gluteus medius had atrophied and the gluteus the anterior portion deep to the anterior or poste- minimus remained. He assumed that the re- rior edge of the tensor fasciae latae muscle can be sponses to stimulation of the anterior and poste- appreciated. This approach can be visualized by rior portions of the gluteus medius applied noting the attachment of the tensor fasciae latae equally to the gluteus minimus. Although Green- on the ilium in relation to the attachments of the law20 recorded electrical activity separately from gluteus medius and minimus muscles.2,30,35 the anterior and posterior portions of the gluteus medius muscle, he monitored the gluteus mini- 3. INNERVATION mus in only one location, 3.7 cm (1 1\/2 in) above the tip of the greater trochanter, probably sampling its The gluteus minimus muscle is inner- middle fibers. Thus, this study provides limited vated by both the superior and inferior EMG data on the contribution by the gluteus mini- branches of the superior gluteal nerve. mus muscle to medial and lateral rotation of the The superior gluteal nerve passes be- thigh. In another EMG study,80 fine-wire elec- tween the gluteus medius and gluteus trodes were placed in the gluteus minimus 5 cm minimus muscles as it sends branches to (2 in) posterior to the anterior superior iliac spine, both of these muscles. This nerve carries which would be among the anterior or middle fi- fibers from the L4, L5, and S1 spinal bers of the muscle. These authors reported activ- nerves.9 ity with abduction and medial rotation of the thigh, as would be expected of the anterior fibers, 4. FUNCTION but not with lateral rotation. Actions The functional relationship of the gluteus mini- mus to the gluteus medius is also influenced by All fibers of the gluteus minimus muscle the fact that the gluteus minimus is considerably contribute to abduction of the thigh when smaller than the gluteus medius muscle. Inman23 the distal part of the lower limb is free to found that, in five cadavers, the weight ratio be- move. The fan-shaped arrangement of fi- tween the gluteus minimus and gluteus medius bers in this muscle corresponds closely to was nearly 1:2. Weber58 in one specimen and the fiber arrangement in the overlying Voss57 in 12 specimens reported that the weight gluteus medius. Both muscles attach to ratios of gluteus minimus to gluteus medius to the same bones at adjacent locations; gluteus maximus closely approximated 1:3:6. therefore, the actions of corresponding Mean fiber lengths for the gluteus minimus and anterior or posterior fibers of the gluteus gluteus medius were 4.8 cm and 6.8 cm, respec- minimus and gluteus medius muscles are tively.58 similar. As with the gluteus medius, the ante- rior fibers of the gluteus minimus are con-","Chapter 9 \/ Gluteus Minimus Muscle 173 The evolutionary transition of the gluteus rather than in the gluteus minimus. Low medius and gluteus minimus from propulsive to back pain in the sacral and sacroiliac re- stabilizing muscles of ambulation is well de- gions is more likely to be due to TrPs in scribed and illustrated.29 the gluteus medius than in the gluteus minimus muscle; the latter rarely, if ever, 5. FUNCTIONAL (MYOTATIC) UNIT causes pain in this area. Medial rotation at the hip by the anterior Other Myofascial Syndromes gluteus minimus and tensor fasciae latae muscles is assisted by the anterior fibers Distinguishing gluteus minimus TrPs of the gluteus medius muscle. This action from those in the piriformis and the over- is opposed chiefly by the gluteus max- lying gluteus medius depends partly on imus and piriformis muscles, together the differences in their pain patterns and with the lateral rotator group: the quad- partly on where in the buttock the TrPs ratus femoris, the two gemelli, and the are located. The gluteus minimus and pir- two obturator muscles. iformis lie beside each other with occa- sional overlap, have adjacent attach- Agonists for the hip abduction function ments, and generate somewhat similar of the gluteus minimus muscle are the distributions of referred pain. The piri- gluteus medius and tensor fasciae latae.23 formis pain pattern may occasionally ex- Abduction is countered primarily by the tend as far distally as the knee, whereas four major adductor muscles: the ad- the gluteus minimus pattern usually in- ductores magnus, longus, and brevis with cludes the calf in addition to the thigh. A the pectineus muscle and, to a lesser ex- line drawn to divide the gluteus minimus tent, by the gracilis muscle. from the piriformis is shown in the previ- ous chapter, Figure 8.5B. This piriformis 6. SYMPTOMS line extends from the upper border of the greater trochanter to the upper end of the Patients complain of hip pain that may palpable free border of the sacrum, where cause a limp during walking. Lying on the the palpating finger encounters the ilium affected side may be so painful that roll- near the caudal end of the sacroiliac (SI) ing over onto that side during the night joint. interrupts sleep. After sitting for a while, patients with active TrPs in the anterior Pain referred from the gluteus medius gluteus minimus often have difficulty ris- is less likely to involve the thigh; gluteus ing from the chair and standing up maximus TrPs restrict flexion at the hip, straight56 because the movement becomes while piriformis TrPs restrict medial rota- painful. tion. TrPs in the gluteus minimus are dif- ficult to distinguish by palpation from The pain from TrPs in this muscle can those in the overlying gluteus medius be constant and excruciating. The patient throughout their large area of overlap may not be able to find a stretching move- (Fig. 8.5A). ment or change of position that relieves the pain and can neither lie down com- Radiculopathy fortably nor walk normally. Differential Diagnosis The gluteus minimus is a potent myofas- cial source of pseudoradicular syn- The pain referred from gluteus minimus dromes.39 The symptoms produced by TrPs should be distinguished from that of TrPs in the anterior fibers of the muscle gluteus medius and piriformis TrPs; an may be mistaken for an L5 radiculop- L4, L5, or S1 radiculopathy; trochanteric athy,38,53 and symptoms from the posterior bursitis; and from the pain of articular fibers mimic an S1 radiculopathy.38 Knee (\\\"somatic\\\") dysfunction. Sciatica is a pain that suggests an L4 radiculopathy is symptom, not a diagnosis; its cause should not characteristic of gluteus minimus be identified. TrPs. Sensory or motor deficits and pares- thesias in a nerve-distribution pattern, If the myofascial pain is referred deep imaging of the spine, and electrodiagnos- into the hip joint, the source is probably tic tests distinguish neurogenic from TrP- TrPs in the tensor fasciae latae muscle","174 Part 1 \/ Lower Torso Pain referred pain. The latter is recognized by downward from the buttock over the pos- locating the TrPs and identifying their as- terior or outer side of the lower limb. sociated phenomena. However, a lanci- nating pain is more likely to be indicative The pain may be either myofascial or of radiculopathy or sciatic nerve entrap- neurological in origin. Myofascial TrPs in ment by the piriformis muscle. the posterior gluteus minimus muscle can be a common source of sciatica.47, 53 This Bursitis cause of sciatica is easily overlooked if the clinician does not examine the mus- The pain radiating from trochanteric bur- cles. sitis travels from the buttock along the lat- eral aspect of the thigh to the knee28,40 and Sciatica is usually assumed to be should not be confused with myofascial caused by compression of a nerve. A referred pain. In the patient who has bur- common neurological cause of this pain sitis and is side lying with the hip par- is entrapment of the sciatic and\/or pos- tially flexed, distinct tenderness is elic- terior femoral cutaneous nerves by the ited over the bursa; digital pressure on the piriformis muscle as the nerves exit the bursa reproduces the patient's pain com- pelvis through the greater sciatic fora- plaint. In the presence of trochanteric men (see Chapter 10). Other neurogenic bursitis, the gliding movement of the glu- sciaticas include nerve root compres- teal tendons over the greater trochanter sion by spinal tumors,41 by spinal steno- during stretching of the anterior part of sis,25 or, rarely, by variant fascial the gluteus minimus or the tensor fascia bands,4,48 and compression of the cauda latae muscle becomes exquisitely painful. equina by a herniated lumbar disc (ra- One must determine by physical exami- diculopathy).6,17,25,42,53 Compression and nation for TrPs whether the deep tender- pain may also be caused by an aneu- ness is referred, at least in part, from the rysm.21,59 gluteal and\/or quadratus lumborum mus- cles. Negrin and Fardin33 reported on the follow-up Articular Dysfunction results of 41 patients with acute sciatica (lumbo- Another associated disorder, blockage of sciatalgia) and electromyographically proven movement of the SI joint, may be sus- tained by the persistent asymmetrical monoradicular denervation. Of these, 19 under- muscle tension on the pelvis caused by gluteus minimus TrPs. When this combi- went surgery and 22 were treated medically. nation of SI joint dysfunction and gluteus minimus TrPs appears with restricted Three to eight years later, among the operated pa- mobility of the lowest two intervertebral joints of the lumbar spine and tenderness tients with severe motor impairment, 33% recov- of the L 4 - S 1 spinous processes, this group of findings is characterized by Lewit26 as a ered and 33% improved motor function; in the chain reaction. However, tenderness of the spinous processes may also be re- non-operated group, the initial paralysis remained ferred from TrPs in the adjacent multifidi and rotatores paraspinal muscles. largely unchanged. However, no significant differ- The pain referred by lumbar facet joints ence was reported in pain relief between the oper- is described and illustrated in Chapter 3 on pages 25-26. It often overlaps the pain ated and non-operated groups. The patients were pattern of gluteus minimus TrPs. more concerned about their pain than about their Sciatica motor deficits.33 The pain of these patients appar- Sciatica is a non-specific term commonly applied to the symptom of pain radiating ently was caused as much by associated TrPs, or other disorders of muscles and fasciae, as by the nerve compression. Sheon and associates42 suggest that \\\"pseudosciatica\\\" is a more appropriate diagnosis than \\\"sciatica\\\" when sensory and motor neurological findings are nor- mal. In these cases, they suggest that bur- sitis and myofascial pain probably cause the symptoms. Kellgren24 reported, as noted in Section 1, that, in 50 of 70 cases of sciatica, the pain was caused by liga- mentous and muscular lesions. Others note that many of the patients designated as having sciatica without evidence of","Chapter 9 \/ Gluteus Minimus Muscle 175 neurological disease probably suffer pain The post-lumbar laminectomy pain of myofascial origin.38,61 syndrome39 is frequently caused by resid- ual myofascial TrPs that had been acti- 7. ACTIVATION AND PERPETUATION vated by the radiculopathy, for which a OF TRIGGER POINTS successful laminectomy had been per- formed. These active TrPs remain like Myofascial TrPs in the gluteus minimus dust on the shelf that must be wiped muscle may be activated or perpetuated clean. Such residual gluteus minimus by sudden acute or repetitive chronic TrPs are particularly confusing when they overload, SI joint dysfunction, injection mimic the pain for which the laminec- of medications into the muscle, and nerve tomy was performed. root irritation. Perpetuating factors may include prolonged immobility, tilting the Perpetuation of Trigger Points pelvis by sitting on a wallet, and unstable equilibrium when standing. Prolonged immobility is a potent source of aggravation of TrPs. Since the position Activation of Trigger Points of the right foot is fixed on the accelerator when one drives a car, the right hip mus- Gluteus minimus TrPs may be activated cles are effectively immobilized unless a by an acute overload imposed by a fall; by special effort is made to reposition the walking too far or too fast, especially on thigh and hip. Automatic cruise control rough ground; or by overuse in running permits safe intermittent repositioning of and sports activities, such as tennis and the foot, knee, and hip. handball. Distortion of the normal gait sufficient to induce gluteus minimus TrPs The gluteus minimus and gluteus was caused in one case by a painful blis- medius muscles are relatively immobi- ter on the foot and, in another case, by lized during prolonged standing, as when walking extensively for 2 days while waiting in line or when standing at a limping on a painful knee. cocktail party. Unless the individual fre- quently shifts weight from one lower limb In the senior author's experience,56 re- to another, the latent TrPs may become ferred pain in the lower limbs following active. SI joint displacement results most fre- quently from TrPs located in the gluteus Sacroiliac joint dysfunction can both minimus muscle. The next most likely activate and perpetuate these gluteal muscles to be involved with SI joint dys- TrPs. function are the erector spinae, quadratus lumborum, gluteus medius, gluteus max- Sitting on a wallet placed in a long back imus, piriformis, and, less frequently, the pocket can impinge on gluteus minimus adductors of the thigh.56 TrPs and produce referred pain in a sciat- iclike distribution.19 The gluteus minimus is the least desir- able of the gluteal muscles as a site for in- When standing, if the feet are placed tramuscular injection of irritant medica- close together, the base of support is re- tion; neither the gluteus maximus nor the duced. For those who have suffered a loss gluteus medius muscle is as prone to de- of equilibrium, the resultant unsteadiness velop TrPs following medication injec- can increase the demands on the gluteus tions as is the gluteus minimus.52 The minimus and gluteus medius muscles, minimus is too deep to permit easy iden- chronically overloading them. tification of spot tenderness caused by la- tent TrPs. Latent TrPs in this muscle, 8. PATIENT EXAMINATION when activated by injection of irritant medications, can refer severe \\\"sciatica\\\" Patients with gluteus minimus TrPs ex- that may last for months. The gluteus hibit some degree of antalgic gait, which minimus muscle and the nearby sciatic may be so severe that they must either nerve can be avoided by injecting the limp awkwardly or walk with a cane. medication into the gluteus medius mus- When the TrPs are very hyperirritable, cle in the upper outer quadrant of the but- the seated patient is unable to cross the tock, or into the deltoid muscle. affected leg over the opposite knee be- cause of painfully restricted adduction. Passive stretch of the involved muscle is","176 Part 1 \/ Lower Torso Pain Figure 9.5. Flat palpation of TrPs in the anterior and posterior portions of the right gluteus minimus muscle. The open circle marks the greater trochanter. The solid circle identifies the anterior supe- rior iliac spine and terminates the solid line, which follows the crest of the ilium. The dotted line outlines the gluteus mini- mus muscle and the Xs locate its trigger points. A, palpation of an anterior glu- teus minimus TrP deep to the posterior border of the tensor fasciae latae mus- cle, with the patient supine. The adjacent small X is an intermediate TrP between the anterior and posterior parts of the muscle. The large X locates the most common TrP in the posterior part of the muscle. S, with the patient side lying, palpation of the most frequent posterior TrP (large X in A). The two most poste- rior small Xs locate less common poste- rior TrPs. The more anterior small X is the intermediate trigger point noted above in A. The most anterior, incom- plete large X identifies the most common anterior trigger point. The uppermost thigh is positioned in about 30\u00b0 of flexion and in as much adduction as is comfort- able, using the pillow to support the up- permost thigh. limited in range and is painful; active feel the tension of taut bands deep in the contraction is likely to elicit \\\"ratchety\\\" buttock, and snapping palpation of active weakness. Altered sensations of pain, TrPs in the posterior fibers of the gluteus dysesthesia, or numbness may be elicited minimus may rarely induce a thigh jerk in the pain reference zone. Otherwise, no caused by a local twitch response. Occa- neurological deficits are observed due to sionally, the referred pain pattern can be gluteus minimus TrPs. induced by sustained pressure on the ten- der TrP, but pain referred from this mus- 9. TRIGGER POINT EXAMINATION cle usually is evoked only by a needle en- (Fig. 9.5) countering its TrPs. Myofascial TrPs in the gluteus minimus Anterior Trigger Points muscle usually lie deep to both the glu- teus maximus and the gluteus medius For examination of anterior gluteus mini- muscles or deep to the tensor fasciae mus TrPs, the patient lies supine, as illus- latae. Therefore, taut bands in the gluteus trated in Figure 9.5A, with the thigh of the minimus are unlikely to be palpable, but affected limb extended to the limit of TrP spot tenderness can be clearly local- comfort. If necessary, the knee is sup- ized. Occasionally, if the overlying glu- ported by a pillow. The anterior superior teal muscles are fully relaxed, one can iliac spine is palpated at the anterior end","Chapter 9 \/ Gluteus Minimus Muscle 177 of the iliac crest. The tensor fasciae latae per border of the piriformis muscle (see muscle is identified by asking the patient black line in Chapter 8, Fig. 8.58). The pir- to try to rotate the thigh medially against iformis line begins 1 cm (1\/2 in) cephalad resistance while the clinician palpates to to the upper edge of the palpable protu- locate the tensed muscle that lies just berance of the greater trochanter (attach- under the skin. ment of piriformis tendon) and runs to the upper end of the palpable border of The anterior fibers of the gluteus mini- the sacrum just below the SI joint, where mus are then explored for TrP tenderness the piriformis muscle enters the pelvis. by palpating deeply, first anterior to and then posterior to the tensor fasciae latae The region of the most posterior TrPs in muscle, just distal to the level of the ante- the gluteus minimus muscle can be esti- rior superior iliac spine. In some patients, mated by use of the black (piriformis) line a thin layer of gluteus medius muscle in Figure 8.58. These TrPs are found su- may cover all of this anterior portion of perior to that line between its midpoint the gluteus minimus.35 In other patients, and the junction of its middle and lateral the gluteus medius may cover the gluteus thirds (Fig. 9.58 and Fig. 8.58). The most minimus muscle deep to the posterior inferior (posterior) dotted line in Figure border, but not the anterior border, of the 9.5 is in the same location as the piri- tensor fasciae latae muscle.2,16,30 Thus, ex- formis line of Figure 8.58. amining deep to the anterior border of the tensor fasciae latae muscle is usually 10. ENTRAPMENTS more satisfactory when palpating for the spot tenderness of anterior gluteus mini- No neurological entrapments have been mus TrPs. identified as being due to tension in- duced by TrPs in this muscle. The accessibility of the anterior fibers of the gluteus minimus muscle to direct 11. ASSOCIATED TRIGGER POINTS palpation depends on the location of the overlying fibers of the tensor fasciae latae, Active myofascial TrPs in the gluteus and possibly the gluteus medius muscle, minimus muscle rarely present as a sin- in that individual (see Section 2). The gle-muscle syndrome. The TrPs in this lowest cross section in Figure 9.4 shows muscle are most often observed in associ- how spot tenderness in the gluteus mini- ation with TrPs in the piriformis, gluteus mus may be elicited by deep palpation medius, vastus lateralis, peroneus longus, applied along either the anterior or poste- quadratus lumborum, and, sometimes, rior margin of the tensor fasciae latae the gluteus maximus muscle. muscle. Which site is most useful de- pends on individual anatomical varia- The two muscles that are most closely tions of the ilial attachments of these two associated functionally with the gluteus muscles. The ilial attachments portrayed minimus (the gluteus medius and the pir- by McMinn and Hutchings30 would per- iformis) are also the most likely to de- mit direct access to the gluteus minimus velop secondary TrPs. The posterior fi- only along the anterior border of the ten- bers of the gluteus minimus and the sor fasciae latae slightly lateral and distal piriformis muscle frequently develop as- to the anterior superior iliac spine. sociated TrPs. Similarly, the anterior fi- bers of the gluteus minimus and the ten- Posterior Trigger Points sor fasciae latae are closely related func- tionally and may develop associated To locate strongly active TrPs in the TrPs. The fact that the flexion and exten- posterior portion of the gluteus minimus, sion functions of the gluteus minimus are the patient lies on the uninvolved side inconstant and variable37 accounts for the with the uppermost thigh adducted and lack of associated functional unit TrPs in slightly flexed to about 30\u00b0 (Fig. 9.56). the hamstring and calf muscles. The lower posterior (medial) border of The vastus lateralis may develop TrPs the gluteus minimus muscle is identified that are satellites to those in the anterior by locating the piriformis line that repre- part of the gluteus minimus muscle. sents its common boundary with the up- Myofascial TrPs commonly develop in the posterior portion of the gluteus","178 Part 1 \/ Lower Torso Pain Figure 9.6. Stretch positions and intermittent cold the pull of gravity, fully elongating the anterior portions patterns (thin arrows) for TrPs in the anterior and pos- of the gluteus minimus and gluteus medius. B, to inac- terior portions of the gluteus minimus muscle. The jet tivate posterior TrPs, the thigh is flexed 30\u00b0 at the hip, stream of the vapocoolant spray or ice covers first the medially rotated, and then adducted by the pull of TrP region of the muscle and then its referred pain gravity as intermittent cold is applied. An alternative pattern. The thick arrows identify the direction of position is to swing the lower limb over the side of the movement to stretch the muscle passively. In the treatment table as illustrated in Figure 8.6 for the glu- stretch position shown, the lower limb extends beyond teus medius; the intermittent cold pattern illustrated in the end of the table. A, for inactivation of anterior TrPs, this figure is also used with the alternative position. the thigh is gradually extended while it is adducted by minimus muscle, and less frequently in Similarly, the peroneus longus, which the anterior portion, as satellites to lies in the pain reference zone of the ante- quadratus lumborum TrPs. This cou- rior part of the gluteus minimus, has been pling can be so strong that pressure ex- seen to develop satellite TrPs from that erted on the quadratus lumborum TrPs part of this gluteal muscle. induces not only the expected referred pain in the buttock but also unexpected 12. INTERMITTENT COLD WITH pain referred down the back of the STRETCH lower limb. This additional pain results (Fig. 9.6) from activation of satellite TrPs in the posterior part of the gluteus minimus; Details of using intermittent cold with pressure applied to these gluteal TrPs stretch are found in Volume 1 on pages elicits the same lower limb pain. Some- 63\u201474 for the stretch-and-spray technique times elimination of the quadratus lum- and in Chapter 2 on page 9 of this volume borum TrPs inactivates the satellite glu- for the application of ice instead of vapo- teal TrPs. In other patients, TrPs in the coolant spray. two muscles must be inactivated sepa- rately. Intermittent cold with stretch can be applied to the gluteus minimus muscle with the patient lying on the uninvolved","Chapter 9 \/ Gluteus Minimus Muscle 179 side and the buttocks close to the end of Posterior Fibers the treatment table (Fig. 9.6A and B). The lower limb to be treated extends over the For TrPs in the posterior fibers (Fig. end of the table, but is supported by the 9.6B), the patient lies on the uninvolved operator to avoid overloading the in- side with the involved limb hanging over volved muscle. The patient may grasp the the end of the table. The thigh of the limb side of the table for stabilization. to be treated is flexed to only about 30\u00b0. This positions the trochanteric attach- For intermittent cold with stretch, one ment of the gluteus minimus so that ad- must first determine whether the TrPs are duction at the hip produces maximum located in the anterior or the posterior fi- lengthening. The pull of gravity is either bers of the gluteus minimus. lessened or augmented as described pre- viously for the anterior part of the muscle. Anterior Fibers Alternative positions for intermittent To release TrP tension in the anterior fi- cold with stretch of the anterior and pos- bers, the thigh of the opposite (nonin- terior parts of the gluteus minimus are volved) lower limb is flexed at the hip to presented in Section 12 of Chapter 8 (Fig. stabilize the patient's pelvis (Fig. 9.6A). If 8.6A and 6 ) , and have been described the knee of the limb being treated is elsewhere.43,45 flexed about 90\u00b0 (not shown in the figure), gravity tends to produce some lateral ro- Parallel sweeps of vapocoolant or ice tation of the thigh, which helps to elon- are applied over the posterior portion of gate the anterior fibers of the muscle. the muscle and continued distalward over the posterior buttock, thigh, and calf The edge of a plastic-wrapped block of to the ankle, covering all of the pain refer- ice or the jet stream of vapocoolant spray ence zones. As the thigh is gently lowered is applied in parallel sweeps first over the into adduction, relaxation is augmented, anterior half of the muscle and then over as described previously, by asking the pa- the pain reference zones\u2014the buttock, tient to exhale slowly while parallel lateral thigh, and leg\u2014as depicted in Fig- sweeps of intermittent cold are applied. ure 9.6A The anterior fibers are passively This intermittent-cold-with-stretch se- lengthened by first moderately extending quence is repeated until full range of mo- the thigh and then adducting it by gently tion is reached or until no further gains allowing the foot to ease further down- occur. ward toward the floor, assisted by gravity. At first, the operator may need to support After the procedure has been com- part of the weight of the limb. As TrP ten- pleted, the skin is rewarmed promptly sion eases, the full effect of gravity is tol- with a moist heating pad. Then the pa- erated. Finally, for some patients, gentle tient actively moves the limb slowly pressure may be added to assist the pull through the full range of motion in abduc- of gravity. The patient can look upward tion and adduction at least three times to during inhalation, which encourages gen- help restore normal muscle function. tle isometric contraction, and then look downward and \\\"let go\\\" during exhalation Other muscles in the functional unit of to augment relaxation. the posterior part of the gluteus minimus are the posterior fibers of the gluteus Other muscles that form a functional medius, which have an overlapping pain unit with the anterior part of the gluteus pattern and a similar stretch position, the minimus include the anterior fibers of the piriformis, and the gluteus maximus. gluteus medius and the tensor fasciae However, the gluteus maximus pain refer- latae. All three muscles have overlapping ence zone and intermittent cold pattern pain patterns and similar stretch posi- may include the sacral region; also, the tions and should be released by intermit- gluteus maximus requires full flexion of tent cold with stretch of the gluteus mini- the thigh at the hip for its complete pas- mus. However, for full lengthening of the sive stretch (see Fig. 7.5 in Chapter 7). tensor fasciae latae muscle, the thigh should be rotated laterally. Alternative Methods Another stretch position is portrayed by Evjenth and Hamberg.11 They strap the","180 Part 1 \/ Lower Torso Pain side-lying patient to a plinth with the pa- The method of locating the most anterior tient lying on the involved gluteus mini- gluteus minimus TrPs has been described mus, which renders the muscle and re- in Sections 2 and 9 of this chapter. ferred pain pattern inaccessible to spray and requires the operator to stretch the The clinician localizes a TrP in the an- muscle by lifting the lower limb against terior gluteus minimus muscle by deep gravity. The positions that we prefer in- palpation and notes carefully the precise stead for passive lengthening of the mus- direction of pressure that elicits maxi- cle are assisted by gravity, and the patient mum tenderness. When inactivating can be taught to use these positions, gluteal TrPs by injection, distinguishing which are shown in Figures 9.6 and 9.8, whether the tender spot is in the gluteus in a home self-stretch program. medius or the gluteus minimus is not crit- ical. Usually, multiple probing move- In many patients, the gluteus minimus ments of the needle in a fanlike pattern in is too deep to permit effective digital is- the region of maximum tenderness are re- chemic compression. If compression is quired to inactivate a cluster of TrPs. It is tried, it usually requires the pressure of essential that the needle penetrate far two hands applied with one thumb on enough in the direction of spot tender- top of the other. Some operators recom- ness to reach the deepest gluteus mini- mend use of the elbow; we consider this mus fibers. A 50-mm (2-in) or 62-mm (21\/2- less desirable because the operator may in) needle may be required. not feel the nature of the tissues being compressed, resulting in less precise lo- In this muscle, needle contact with the calization of pressure and in the appli- TrP usually evokes the predictable pat- cation of excessive force. Application of tern of referred pain that the patient can pressure distal and medial to the gluteus describe in detail, if requested ahead of minimus muscle over the sciatic nerve time to note any pain radiation. may cause a tingling, painful sensation and possibly neurapraxia. Production If the needle passes through the gluteus of these nerve compression symptoms minimus, the needle encounters either should be avoided. the ilium or the capsule of the hip joint. The needle should be replaced immedi- The tennis-ball technique described ately if contact with bone has bent its tip and illustrated in the previous chapter for and its movement through the muscle TrPs in the gluteus medius muscle (Chap- produces a scratchy sensation. Such en- ter 8, Section 14 and Fig. 8.9) enables the counters with the periosteum are usually patient to apply ischemic compression to painful to the patient only momentarily. himself or herself (Section 14, this chap- ter). Posterior Fibers 13. INJECTION AND STRETCH For injection of TrPs in the posterior fi- (Fig. 9.7) bers, the patient is placed fully side lying on the uninvolved side (Fig. 9.7C). Fre- For injection, gluteus minimus TrPs must quently, there are multiple TrPs in this be precisely localized and their relation part of the muscle. Posterior TrPs are lo- to the sciatic nerve identified. It is prefer- cated by palpation as noted in Section 9. able to inject any gluteus maximus and The lower posterior border of the gluteus gluteus medius TrPs before attempting to minimus is located by defining the upper inject gluteus minimus TrPs. The in- limit of the piriformis muscle. Directing creased TrP tension of the overlying mus- the needle above, not below, this line and cles and their additional tender spots in an upward direction normally elimi- make the precise localization of gluteus nates the risk of accidentally penetrating minimus TrPs unnecessarily difficult. the sciatic nerve as it exits the pelvis through the sciatic foramen. Injection is Anterior Fibers then performed essentially as described previously for the anterior fibers. For injection of TrPs in the anterior fibers, the patient is propped up partly side ly- After completion of each probing by the ing (Fig. 9.7-4) or lies supine (Fig. 9.76). needle, prompt hemostasis is applied by the palpating hand as the needle is with-","Chapter 9 \/ Gluteus Minimus Muscle 181 Figure 9.7. Injection of TrPs (Xs) in the anterior and posterior parts of the right gluteus minimus muscle. The solid line follows the crest of the ilium to the ante- rior superior iliac spine (solid circle). The dotted line marks the borders of the glu- teus minimus muscle and indicates its attachment to the greater trochanter (open circle). A, probing close to the posterior border of the tensor fasciae latae muscle to locate anterior gluteus minimus TrPs (anterior large X). B, prob- ing under the anterior border of the ten- sor fasciae latae muscle to inject the trig- ger-point location shown in A by the large anterior X. C, injection of the most common posterior gluteus minimus TrPs (in the area marked by the posterior large X in A and B). drawn. Prolonged superficial capillary All Fibers oozing may indicate low tissue reserves of ascorbic acid. If possible, aspirin medi- After injection, the clinician should reex- cation should be discontinued several amine the site for residual tenderness to days before TrP injection to reduce local detect any remaining active TrPs. Injec- bleeding. tion is followed by passive stretch, then","182 Part 1 \/ Lower Torso Pain by active abduction and adduction vated not only by direct chilling of these through full range of motion at the hip. muscles, but also by cooling of the body The application of a moist heating pad or as a whole. hot pack also helps restore normal func- tion of the muscle and minimize post- If intramuscular medicinal injections injection soreness. must be given in the buttock, they should not be injected as deep as the gluteus Immediately following injection, one minimus muscle. can conclude that the TrP was probably penetrated and inactivated if: (a) injection Corrective Posture and Activities elicited a local twitch response, (b) deep spot tenderness at the site of injection dis- For patients with active gluteus minimus appears within a few minutes, (c) sponta- TrPs, standing is more painful than sit- neous pain and tenderness in the reference ting. They should be encouraged to sit zone disappear or diminish, and (d) there whenever possible, especially in situa- is an appreciable increase in the range of tions where one usually stands, as when motion.56 Surprisingly, reproduction of the working in the kitchen. If standing is una- patient's referred pain pattern during in- voidable, weight should be shifted regu- jection is not conclusive; the needle may larly from one foot to the other. Relief by only be pressing against the outside of the this alternation of weight bearing and TrP, thus setting off the referred pain. A change of position is enhanced if one foot similar (usually more intense) pain is ex- is placed on a footrest that is elevated 5- perienced when the needle actually pene- 7.5 cm (2 or 3 in). The feet should be sep- trates the TrP and inactivates it. arated to widen the base of support. Even when sitting, it is helpful to change posi- When a very active TrP in this muscle is tions every 15 or 20 minutes by standing injected, a sensation of heaviness or weak- up, moving around the room, and sitting ness of the limb may ensue within a min- down again. An interval timer placed ute or two. The muscle is capable of a brief across the room is a helpful reminder to contraction in response to voluntary effort, change positions when a person is preoc- but is unable to maintain the contraction. If cupied with a task. the patient attempts to stand on the in- jected limb immediately, the hip may \\\"give When an individual sleeps on the side way\\\" and the patient may fall. When 0.5% with the thighs flexed, a pillow between procaine solution is used, this weakness the knees and legs helps maintain the up- should last, at most, 15 or 20 minutes.56 permost thigh horizontal and the in- Precautions should be taken by allowing volved gluteus minimus muscle in a neu- the patient to rest for a suitable period of tral position, as illustrated in the follow- time following the injection, while moist ing chapter in Figure 10.10. heat is applied, and by testing the motor power of the limb before weight bearing is A hemipelvis that is small in the ante- attempted. This weakness is similar to that roposterior diameter can be a significant which would occur if some of the local an- perpetuating factor for gluteus minimus esthetic solution reached the sciatic nerve. and gluteus medius TrPs, causing a twist- ing tilt of the pelvis whenever the patient 14. CORRECTIVE ACTIONS is lying supine. This should be corrected (Fig. 9.8) by an ischial lift, as illustrated in Figure 4.12B. The obese patient should undertake a weight-loss program, but not by excessive Displacement of the sacroiliac joint exercise that overloads the gluteal mus- should be corrected by mobilization32 or cles. The wide-based waddling gait manipulation55,56 techniques. adopted by very obese patients reduces demands on the gluteus minimus and Patients with symptoms from posterior gluteus medius muscles. gluteus minimus TrPs should carry the wallet elsewhere than in the back pocket. The patient with gluteus minimus TrPs The wallet can cause \\\"back-pocket sciat- should keep the body warm. Latent TrPs i c a \\\" 1 9 when sitting on it compresses a glu- in the gluteal muscles are readily acti- teus minimus TrP, and it can also tilt the pelvis (see Chapter 4)."]