142 K. Baessler and H.Kiilbl abdominis muscle contraction. Neurourol Urodyn. 34. Peschers UM, Fanger G, Schaer GN, et al. Bladder 2003;22:582-588. neck mobility in continent nulliparous women. 21. Nguyen JK, Hall CD, Taber E, et al. Sonographic BJOG. 2001;108:320-324. diagnosis of paravaginal defects: a standardiza- tion of technique. Int Urogynecol J Pelvic Floor 35. Howard D, Miller JM, Delancey JO, et al. Differen- Dysfunct.2000;11:341-345. tial effects of cough, valsalva, and continence 22. Schaer GN, Schmid T, Peschers U, et al. Intraure- status on vesical neck movement. Obstet Gynecol. thral ultrasound correlated with urethral histol- 2000;95:535-540. ogy. Obstet Gynecol 1998;91:60-64. 23. Fischer JR, Heit MH, Clark MH, et al. Correlation 36. Miller JM, Perucchini D, Carchidi LT, et al. Pelvic of intraurethral ultrasonography and needle elec- floor muscle contraction during a cough and tromyography of the urethra. Obstet Gynecol. decreased vesical neck mobility. Obstet Gynecol. 2000;95:156-159. 2001;97:255-260. 24. Umek WH, Obermair A, Stutterecker D, et al. Three-dimensional ultrasound of the female 37. King JK, Freeman RM. Is antenatal bladder neck urethra: comparing transvaginal and transrectal mobility a risk factor for postpartum stress incon- scanning.Ultrasound Obstet Gynecol.2001;17:425- tinence? Br J Obstet Gynaecol. 1998;105:1300-1307. 430. 25. Chen GD, Lin LY, Gardner JD, et al. Dynamic dis- 38. Schaer GN, Perucchini D, Munz E, et al. Sono- placement changes of the bladder neck with the graphic evaluation of the bladder neck in con- patient supine and standing. J Urol. 1998;159:754- tinent and stress -incontinent women. Obstet 757. Gynecol. 1999;93:412-416. 26. Dietz HP, Clarke B. The influence of posture on perineal ultrasound imag ing parameters. Int 39. Schaer GN, Koechli OR, Schussler B, et al. Useful- Urogynecol J Pelvic Floor Dysfunct. 2001;12:104- ness of ultrasound contrast medium in perineal 106. sonography for visualization of bladder neck 27. Brandt FT, Albuquerque CD, Lorenzato FR, et al. funneling-first observations. Urology. 1996;47: Perineal assessment of urethrovesical junction 452-453. mobility in young continent females. Int Urogyne- col J Pelvic Floor Dysfunct. 2000;11:18-22 . 40. SchaerGN, Koechli OR,Schiissler B,et al. Improve- 28. Peschers UM, Vodusek DB, Fanger G, et al. Pelvic ment of perineal sonographic bladder neck imag- muscle activity in nulliparous volunteers. Neuro - ing with ultrasound contrast medium. Obstet urol Urodyn . 2001;20:269-275. Gynecol. 1995;86:950-954. 29. Reed H, Freeman RM, Waterfield A, et al. Preva- lence of bladder neck mobility in asymptomatic 41. Dietz HP, Clarke B. Translabial color Doppler uro - non-pregnant nulliparous volunteers. BJOG. 2004; dynamics. Int Urogynecol J Pelvic Floor Dysfunct. 111:172-175. 2001;12:304-307. 30. Dietz HP, Eldridge A, Grace M, et al. Pelvic organ descent in young nulligravid women. Am J Obstet 42. Alper T, Cetinkaya M, Okutgen S, et al. Evaluation Gynecol 2004;191:95-99. of urethrovesical angle by ultrasound in women 31. Reilly ET, Freeman RM, Waterfield MR, et al. Pre- with and without urinary stress incontinence. Int vention of postpartum stress incontinence in pri- Urogynecol J Pelvic Floor Dysfunct . 2001;12:308- migravidae with increased bladder neck mobility: 311. a randomised controlled trial of antenatal pelvic floor exercises. BJOG. 2002;109:68-76. 43. Wijma J, Potters AE, de WolfBT, et al. Anatomical 32. Lin LY, Chen SY, Lee HS, et al. Female bladder and functional changes in the lower urinary tract neck changes with position. Int Urogynecol J following spontaneous vaginal delivery. BJOG. Pelvic Floor Dysfunct. 1999;10:277-282. 2003;110:658-663. 33. Meyer S, De Grandi P,Schreyer A, et al. The assess- ment of bladder neck position and mobility in 44. Dietz HP, Jarvis SK, Vancaillie TG. The assess- continent nullipara, mulitpara, forceps-delivered ment of levator muscle strength: a validation of and incontinent women using perineal ultra- three ultrasound techniques. Int Urogynecol J sound: a future office procedure? Int Urogynecol Pelvic Floor Dysfunct 2002;13:156-9. J Pelvic Floor Dysfunct. 1996;7:138-146. 45. Peschers U, Schaer G, Anthuber C, et al. Changes in vesical neck mobility following vaginal deliv- ery. Obstet Gynecol. 1996;88:1001-1006. 46. Morkved S, Salvesen K. Pelvic floor muscle strength and thickness of the pelvic floor muscles in continent and incontinent nulliparous women. Neurourol Urodyn. 2001;21:358-359. 47. Schaer GN, Siegwart R, Perucchini D, et al. Exami- nation of voiding in seated women using a remote- controlled ultrasound probe . Obstet Gynecol. 1998;91:297-301.
2.6. Ultrasound Imaging 143 48. Dietz HP, Wilson PD, Clarke B. The use of 50. Sapsford R. Rehabilitation of pelvic floor muscles perineal ultrasound to quantify levator activity utilizing trunk stabilization. Man Ther. 2004;9: and teach pelvic floor muscle exercises. Int 3-12. Urogynecol J Pelvic Floor Dysfunct. 2001;12:166- 168. 51. Solomon MJ, Pager CK, Rex J, et al. Randomized, controlled trial of biofeedback with anal manom- 49. Peschers UM, Gingelmaier A, Jundt K, et al. Evalu- etry, transanal ultrasound, or pelvic floor retrain- ation of pelvic floor muscle strength using four ing with digital guidance alone in the treatment of different techniques. Int Urogynecol J Pelvic Floor mild to moderate fecal incontinence. Dis Colon Dysfunct. 2001;12:27-30. Rectum. 2003;46:703-710.
2.7 Magnetic Resonance Imaging Thomas Treumann, Ralf Tunn, and Bernhard Schussler Key Message tion of structural damage to pelvic organs and pelvic floor structures, e.g., as a result of The aim of this chapter is to briefly introduce the childbirth. technical background of MRI, to provide insight • Cross-sectional images in various planes. This into the anatomy of the pelvis and pelvic floor, to allows for a three-dimensional understanding outline the possible damage to the pelvic floor of organ position and movement. (part 1), and to depict dynamic changes in the • Generation of dynamic sequences. This offers pelvis and pelvic floor during contraction, strain- the ability to depict changes in the pelvic floor ing, and defecation (part 2). and pelvic organ prolapse during contraction, coughing, and straining. Introduction and Technique The cross-sectional imaging techniques currently being used are ultrasound (US),computed tomog- Stress urinary incontinence and genital prolapse raphy (CT), and magnetic resonance imaging are clinical entities that originate from changes (MRI). Apart from the fact, that MRI is the most of soft tissue structures, i.e., pelvic floor muscles expensive of the three techniques, it is the only (PFMs), nerves, and connective tissues, sur- technique that matches all four requirements; rounding the pelvic organs . Clinical examination therefore, it is superior to US and CT in pelvic of the perineal region, the PFMs, the vagina, and floor imaging. rectum at rest, at Valsalva maneuver, and during PFM contraction (see Chapter 2.1) allow for a When conservative treatment is planned, MRI basic assessment of various parameters, such as is not a necessary precondition. However, it hypermobility of the urethra, muscle function, serves well for two reasons: and pelvic organ prolapse. However, when metic- ulous assessment of the underlying changes in 1. To understand functional anatomy of PFMs anatomy is needed, imaging techniques may offer and sphincters under dynamic conditions and, better insight. thus, to enhance the results of clinical inspection and palpation in dysfunction of the pelvic floor. Imaging techniques, when applied for this purpose, should meet the following criteria: 2. To visualize soft tissue damage. • Large field-of-view imaging. This gives an MRI Technique overview over the pelvis and the pelvic floor with the position, size, and structure of the Magnetic resonance imaging is based on the pelvic organs. property of magnetism of the atomic nucleus of hydrogen. Hydrogen is present in nearly every • High spatial resolution and high soft tissue molecule of the human body. When exposed to contrast. This allows for the separate visualiza- 144
2.7. Magnetic Resonance Imaging 145 an external magnetic field, the nucleus of the 1. Multiple parallel slices with the same tech- hydrogen atom begins to rotate around the lon- nical characteristics (plane, resolution, and con- gitudinal axis of the magnetic field. In this state , trast) , acquired together as a block or stack of the nucleus can be excited by radio frequency images over a certain period of time. electromagnetic waves. After some time, the 2. As a dynamic sequence of the same image nucleus is emitting the absorbed energy in the at different points of time, repeated at the same form of similar radiofrequency waves. This is position, while the patient is exercising (e.g., con- called the relaxation process . The answering traction or straining). A sequence of such images waves can be registered by an antenna outside the is a dynamic sequence and can be arranged as a patient and are used for the calculation of cross- movie (see DVD). sectional images. The images have a high soft- tissue contrast. By applying different forms of radio frequency excitations, the tissue contrast Static MRI can be varied. Thus, tissues can be characterized by MRI. The main image-contrast types are Anatomy, Normal Variation, and Pathology called Tl-weighted and T2-weighted images. Images with intermediate contrast are called The best results for static imaging are obtained proton density (PD) images.' in high-field MR systems with a magnetic field strength of 1.5 Tesla units. Such systems are A single MR image represents one slice of the closed ring units with a tube-like gantry in hori- human body. A slice is characterized by its zontal orientation, where the patient is brought imaging plane (transverse, coronal, or sagittal) into the magnet in the supine or prone position. (Fig. 2.7.1), by its slice thickness (i.e., l-lOmm or For pelvic organs, T2-weighted images are supe- more), and by its position in relation to the center rior to Tl -weighted images. For PFMs, PD images of the magnetic field. Images are depicted in two are superior to Tl- and T2-weighted images. The ways: spatial resolut ion should be below 1mm. The slice thickness should be 3 mm or 4 mm. Acquisi- onal Plane tion time for a series is usually between 3 and 5 minutes, depending on the characteristics of the MRI system and on the spatial resolution of the image resolution. Static MRI of the pelvic floor in the supine position holds great promise because ofits poten- tial for identifying injuries to muscles and fascia of the pelvic floor. It allows muscle thickness to be measured. Anatomical variation between normal women, as well as anatomic changes in pelvic floor dysfun ction, can be studied. Although static MRI is not yet ready for clini- cal use, visualization of the anatomy and defects may contribute to a better understanding and, hence, better conservative treatment of patients with pelvic floor disorders. FIGURE 2.7.1. Magnetic resonance imaging imaging planes. MRI: Anatomy inHealthy Nulliparous Women At the level of the middle and proximal urethra, the levator ani muscle sling (the puborectalis and pubococcygeus portion) is seen to the left and the
146 T.Treumann et al, FIGURE 2.7.2. Axialsection atthe level ofmiddle urethra showing athicker muscle (36-year-old nullipara).Note also thatthe muscle difference in levator ani muscle thickness and configuration. In is shaped more like a V in a and more like a Uin b. The closed this and subsequent illustrations, two individuals are compared arrowhead marks the right levator ani muscle and the open withone displayed in theleft column and theother in theright arrowhead marks the insertion ofthearcus tendineus ofthe fascia column. a represents athinmuscle (31-year-old nullipara) and b pelvis intothe pubic bone inb. right, surrounding the levator hiatus and rising At axial planes at the level of midurethral from the inside of the pubic bone . Length, attachment to the arcus tendineous fasciae pelvis area, and volume measures of the levator ani (DeLancey level III), the intact morphology of the muscle vary considerably in continent nullipar- endopelvic fascia is shown with a typical vaginal ous women, with two- to threefold differences configuration because of the musculofascial con- between the minimum and maximum measure nection between the lateral vaginal wall and (Fig. 2.7.2). In 10 % of the women investigated, a levator ani muscle.' The anterior vaginal wall has visible attachment of the levator ani muscle to the a symphysis -oriented, concave (hammock-like or inside of the pubic bone is absent on both the left \"butterfly-shaped\") configuration at the level of and the right (Fig. 2.7.3), and in another 10% it the middle/proximal urethra in all of the nullipa- absent on only one side. This finding is associated rous women investigated (Fig. 2.7.2). Because with a significantly greater mean urogenital of technical difficulties, such as slice thickness, hiatus area, measured on an axial plane at the of the MRI images, however, direct attachment of level of the proximal urethra, compared to those the vaginal wall to levator ani muscle at the level with an intact levator ani muscle attachment. of attachment of the urethra and the bladder base FIGURE 2.7.3. Levator ani muscle thick- ness (closed arrowhead) shown oncoronal images at the level of the urethra (a and b) and the level ofthe rectovaginal space (eand d) comparing thin muscle (a and c; 31-year-old nullipara) with a thicker muscle (b and d; 28-year-old nullipara). Note that the levator ani muscle ends at the perineal membrane (open arrow- head). The puborectal muscle isselected in d (*). B=bladder, 01 =obturator inter- =nus muscle, R rectum.
2.7. Magnetic Resonance Imaging 147 (DeLancey level II and III) (Fig. 2.7.4), as well as Reversible and Permanent Birth-Related the arcus tendenious of the pelvic fascia, is not Changes ofthe Levator Ani Muscle clearly visible in all women. Having understood variations of normal found The three layers of the urethra (mucosa, sub- by MRI, investigating women after childbirth is mucosa/smooth muscle, and striated muscle an exciting technique to elucidate birth-related layer) are reproducible with MRI. The striated changes within muscle and connective tissue . As muscle layer is composed of the circular shaped expected from clinical understanding, a com- external urethral sphincter muscle, the omega plete loss of levator ani tissue was found in a few shaped compressor urethral muscle (proximal women only.' In all women, however, by 1 day urethra; the muscle is covering the anterior part postpartum, the T2-weighted signal intensity of of the urethra and vaginal wall, respectively), and the levator ani muscle was higher compared with the urethrovaginal sphincter muscle (middle the obturator internus muscle. By6 months, these urethra). This composition of the striated muscle differences had disappeared in most women. layer of the urethra causes the dorsal part to appear smaller compared to the lateral and ante- The change in MR signal intensity suggests a rior part (Fig. 2.7.4). There is also a great varia- change in the chemical composition of the muscle tion in diameter area or volume measures of during the first 6 months after delivery. There are these muscles, which parallels findings in the several possible explanations for these observed levator ani muscle. changes . An increase in extracellular fluid, FIGURE 2.7.4. Axial planes at the level of the middle urethra (a Iipara (a, open arrowhead; b, closed arrow) and an indirect con- andb) and bladder base (candd) showingthedifferences inthe relationship between the vagina and the levator ani muscle nection in a 29-year-old nullipara (b, open arrowhead; d, closed (closed arrowhead); both adirect connection ina31 -year-old nul- arrow) are seen. B=bladder, 01 =obturator internus muscle, R= rectum .
148 T. Treumann et al, FIGURE 2.7.5. Changes in T2-signal inten- sity of the LA (arrow) on transverse sections following spontaneous vaginal delivery.32-year-old woman, para 3, (a,b) with higher signal intensity 1day postpar- tum (a) and normal muscle signal intensity 6 months postpartum compared to the obturator internus muscle (arrowhead). glycogenolysis, and accumulation of lactate are the increased size of the urogenital hiatus and the known causes of changes in muscle signal inten- descent of the perineal body, returns to normal sity. Such changes are reflected by an increase in in the resting supine position relatively rapidly, signal intensity on T2-weighted sequences (lighter the internal chemical changes are not completely muscle) and are reversible (Fig. 2.7.5, a and b}Y back to normal as late as 6 months after delivery. Changes in signal intensity caused by a decrease This may reflect different types of parturition- of striated muscle and increase of connective induced changes. In multiparous women the tissue or fat content in the levator ani muscle are signal intensity of the levator ani muscle needs a permanent (Fig. 2.7.5, c and d, and Fig. 2.7.6}.5 longer time (6 months) to return to normal com- pared to primiparous women (2 months). Vaginal birth may lower the perineum and stretch the levator hiatus. However, significant As one with clinical experience might expect, changes at 2 weeks postpartum are suggestive of remarkable variations in levator ani structure a return of normal levator ani geometry.' Eleva- changes are found among different individuals. tion in perineal body position, as well as a One woman's delivery may leave the pelvic floor decrease in the area of the urogenital hiatus by almost unchanged, whereas others may have 27% and of the levator hiatus by 22%. Although profound changes in muscle geometry and the elongation of the muscle, which is reflected by signal intensity. Larger studies are necessary to FIGURE 2.7.6. T2-weighted transverse sections atthelevel ofthebladder neck of a 20-year-old woman, para 1, after spon- taneous vaginal delivery showing disap- pearance ofLA signal atdifferentfollow-up times. (a)Disrupted LA signal in thepara- vaginal region ontheright (arrow) isseen 2 weeks postpartum. (b) Lack of visible signal in the area ofthe right LA (arrow) 6 months postpartum suggests atrophic changes.
2.7. Magnetic Resonance Imaging 149 define the variations in normal recovery and to of the levator ani origin at the pubic bone in some determine what extent postpartum MRI changes continent nulliparous women, which was associ- are associated with long-term pelvic floor ated with a significantly larger urogenital hiatus, dysfunction. makes one suspect that these women have a higher constitutional risk for the development of Women with Stress Urinary Incontinence pelvic floor dysfunction. Comparing the anatomy of the urinary conti- The association of changes in signal intensity nence mechanism in nulliparous continent associated with morphologic and biochemical women and women with stress urinary inconti- muscle changes have been confirmed by studies nence shows a wide range of overlapping find- comparing MRI and histologic findings. MRI ings.2,6 Changes such as the loss of the symphyseal findings also correlate with the results of electro - concavity (\"butterfly\" shape) of the anterior myography studies.\" The increased signal inten- vaginal wall are significantly more common in sity can, thus, be explained by histologically women with stress urinary incontinence, but demonstrated myogenic changes of the PFMs. have also been reported in women without symp- toms and, hence, could be both constitutional The urethral sphincter muscle shows a reduced and delivery related .?\" thickness in its posterior portion (37%), an omega shape (13%), or higher signal intensity (50%); However, recent data in a large series of configurations that are considered abnormal women with stress incontinence have revealed were associated with an increased signal inten- relevant pathomorphologic changes of the levator sity in 70% of women with stress urinary incon- ani muscle, endopelvic fascia, and urethra.\" In tinence. Central defects of the endopelvic fascia the levator ani muscle, unilateral loss of sub- were present in 39% of women and lateral defects stance in approximately one third of women, a were present in 46%. There was a significant asso- higher signal intensity in approximately one ciation between loss of the symphyseal concavity quarter, and alterated origin in approximately of the anterior vaginal wall and lateral fascial one fifth (Fig. 2.7.7). The discovery of an absence defects and levator ani changes. These findings confirm theories on the pathogenesis of stress FIGURE 2.7.7. Axial PO-weighted MR images at the level of the depiction ofitsorigin atthe inner surface ofthe pubic bone (open proximal urethra showing different defects of the levator ani arrow) and atrophy ofanterior muscle portions onthe right where muscle (solid arrowheads) in women with stress urinary inconti- only itsorigin atthe AlLA isdepicted ina48-year-old woman with nence. (a) Bilateral nonvisualization of the origin of the levator stress urinary incontinence. Increased signal intensity of the ani atthe pubic bone while origin at the arcus tendineus levator levator ani relative to theobturator internusmuscle in a51-year- ani (AlLA) is seen (solid arrows) in a 34-year-old woman with old woman withstress urinary incontinence. stress urinary incontinence. (b) Intact levator ani onthe leftwith
150 T. Treumann et al. urinary incontinence, such as the hammock The pubococcygeal line represents a fixed static hypothesis by Del.ancey\" and the integral theory line from the posterior point of the pubis sym- by Petros and Ulmsten. \" In both theories the physis to the last visible coccygeal or sacrococ- intact attachment of the vaginal wall to the levator cygeal intervertebral disk. The H-Line represents ani muscle are considered crucial for maintain- the level of the puborectalis muscle sling and ing continence. leads from the symphysis, to the muscle sling posterior, to the rectoanal junction. Its length Dynamic MRI ofthe Pelvis represents the width of the anogenital hiatus. For this technique, the best results are obtained As a measure for the position of the muscular in high-field systems, with the patient in a supine pelvic floor in relation to the bony pelvis, a third position.\" Although it may be difficult for the line is introduced. The M-line measures the dis- patient to contract, strain, and defecate in the tance of the puborectalis muscle sling to the supine position, dynamic MRI in closed magnets PCL.IS is preferred to MRI in open upright devices such as the Ponare system because closed high-field In asymptomatic nulliparous women, the posi- units offer much better image contrast, spatial tion of the pelvic floor does not exceed 2em below resolution, and temporal resolution, and there- the pubococcygeal line at rest and Sem during a fore allow for more precise evaluation of the Valsalva maneuver. The width of the hiatus pelvis and pelvic floor. Procedural restrictions (H-Line) is between 4 and 6cm at rest, not exceed- seem not to playa major role. Comparison of the ing 8.Scm during Valsalva. An H-line of more two methods has shown that no significant than 9em is considered to be pathologic. pathology was missed in the supine position compared with the upright position during The depth of a rectocele is measured as the dynamic MRI.14 distance from the center of the anal canal to the anterior wall of the rectocele. Anything less than As the urethra, the urethral sphincter, the 3em long is not called a rectocele. The depth of a vagina and uterus, the anal sphincter, the anal cystocele is measured as the distance from the canal, the rectum, and the coccyx are located in internal urethral orifice to the lowest point of the midline of the pelvis, this plane offers optimal the bladder wall. A cystocele starts at 1em in insight into the organs, as far as their reaction to length. PFM contraction and straining is concerned. It has to be kept in mind, however, that the puborec- Visualization ofPFM Function talis muscle sling is mainly located lateral to the midline and is not seen in midline MRIs, except Dynamic MRI sequences (see DVD) visualize for the small part going around the anus posteri- PFM function and changes in the pelvic organs orly. The function of the puborectalis muscle is under various conditions. For physiotherapy assessed indirectly by observation of the shorten- treatment, the understanding of the following ing and widening of the anogenital hiatus (Fig. standard situations of the pelvic floor is impor- 2.7.8, A-C). tant (Fig. 2.7.8, A-C): Standard Reference Lines14 1. Pelvic floor at rest 2. Maximum contraction of the PFMs 3. Maximum relaxation of the PFMs and descent of the pelvic floor and organs during Valsalva maneuver and defecation. For the interpretation and grading of perineal Pelvic Floor at Rest descent and organ prolapse , three main reference lines are used (Fig. 2.7.9): Dynamic MRI investigation of the pelvic floor starts with the pelvic floor in a resting position 1. The pubococcygeal line (PCL) (Fig. 2.7.8A) at normal intraabdominal pressure. 2. The hiatus line (H-Line) Anteriorly, the abdominal wall is seen. The pelvic 3. Descent of the pelvic floor (M-Line) organs are supported by the pelvic floor. Within
2.7. Magnetic Resonance Imaging 151 AB FIGURE 2.7.8. A.12 - weighted images of a 26 year old nullipa- ( rous woman (midline section) Position of pelvic organs at rest. Abd.w. =abdominal wall, Sym. = Symphysis pubis, Urin. 81. = Urinary bladder, U. =urethra, Ut. =uterus, Rect. =rectum, Coco = coccyx, PRM = puborectalis muscle (midline part), An. = anal sphincter and canal. B.Position of pelvic organs during contrac- tion of the pelvic floor muscles. C. Position of pelvic organs Val- salva maneuver. the pelvis, from anterior to posterior, the urinary Anteriorly, the puborectalis muscles are seen in bladder, the vagina, and the rectum can be iden- cross-section lateral to the vagina and urethra. tified. The urethral sphincter muscle is seen below the urinary bladder. The bladder contains Pelvic Floor Contraction urine, and the rectum and vagina are filled with contrast medium. During contraction, the ileococcygeus muscle elevates the pelvic floor, and the puborectalis The puborectalis muscle sling can be identified muscle sling shortens the anogenital hiatus. posterior to the rectoanal junction. Posterior to Pelvic floor contraction elevates the pelvic organs the anorectum, the anococcygealligament leads upwards and moves the urethra towards the to the coccyx. The sacrum, coccyx, and analliga- back of the pubic symphysis . (Fig. 2.7.8 B) ment form the posterior border of the pelvis. In Because the coccyx has remained mobile, it is coronal images, the ileococcygeus muscle is seen pulled anteriorly by tension on the anococcygeal as a curved structure leading from the perineum ligament. to the inner surfaces of the ischium and os pubis.
152 T. Treumann et al, FIGURE 2.7.9. For quantification ofprolapse onMRI, thefollowing In the posterior compartment, the anterior reference lines have gained acceptance: rectal wall may bulge the posterior vaginal wall. 1. The PCl level (PCl) The posterior vaginal wall may be bulged inside 2. H: The width ofthegenital hiatus the vagina or everted to the outside . 3. M:The level ofthePFM in relation tothepubococcygeal level During defecation, the anterior wall of a recto- Quantification of pelvic muscle contraction is cele can move towards the anal canal, leading to completed by measuring the anogenital hiatus a low intussusception. If the puborectalis muscle width and the muscular pelvic floor position in sling does not relax during Valsalva, the rectum relation to the PCL, and then comparing these can be compressed between anococcygeal liga- findings to the corresponding values at rest . An ment and the peritoneal sac or the uterus, leading elevation of the pelvic floor and a shortening of to stool-outlet obstruction or fragmented defeca- the hiatus of 1em are normal values for pelvic tion. In addition to that, the rectum can develop floor contraction (Fig. 2.7.9). an internal intussusception at the point where the rectum is pressed over the hypomochlion of the ileococcygeus muscle (see DVD). The pouch of Douglas usually ends at the vaginal vault. As an anatomic variation, the pouch of Douglas can extend between the rectum and the vagina . Investigations in nulliparous women have shown that the pouch of Douglas can extend as far down as to the level of the pelvic floor, thus, totally separating the posterior vaginal wall from the anterior rectal wall. This is suggested to be the origin of a posterior entero- cele later in life (Fig. 2.7.10).16 Recurrent pressure upon the pelvic floor, relaxation of the PFM, or ventral dislocation of the anterior compartment (e.g., Burch Colposuspension) may lead to a gradual widening of the pouch of Douglas and to Pelvic Floor During Valsalva Maneuver Valsalva maneuver is performed by increasing FIGURE 2.7.10. Open pouch ofDouglas in a 56-year-old female. the intraabdominal pressure while relaxing the Arrows indicate entrance and end ofthis pocket. PFMs. This leads to a descent of the pelvic floor, widening of the anogenital hiatus, elongation of the anococcygeal ligament, and the posterior movement of the pelvic organs. (Fig. 2.7.8 C) In the anterior compartment, the urethra and the bladder rotate around the posterior aspect of the pubic symphysis. In the middle compartment, the vagina and the uterus normally move posteriorly. In genital descent, the vagina shortens and descends , and the uterus goes into an upright position into the longitudinal axis of the vagina and may descend within the vagina down to (descent) or below the pelvic floor (prolapse).
2.7. Magnetic Resonance Imaging 153 A B FIGURE 2.7.11. A. Images ofa 72-year-old female with perineal c descent and an enterocele twenty years after hysterectomy. At rest, there isnormal position ofthepelvic organs. Urinary bladder (Urin.bl.) is filled with urine. Vagina (V) and rectum (Rect) are filled with ultrasound gel. B. During Valsalva manoeuvre, the levator ani is totally effaced and elongated. An enterocele con- taining sigmoid colon (Ent) protrudes into thespace between the vagina (V) and the rectum (Rect). Part ofthe posterior vaginal wall is everted (arrows due to an enormous descent of the perineum relative totheplane between theinterior border border ofthetuber ishiadicum. Furthermore, theanterior rectal wall as well astheposterior vaginal wall are pushed outwards.). * =ure- thral orifice. pb=perineal body. C. MRI ofthesame patient after defecation: After examination ofthe rectum this space is filled with theperitoneal sac, which is descending down totheperineum and everting parts ofthe posterior vaginal wall (arrows). Hiatus width (H) is abnormal with 10 em. Position of muscular pelvic floor (M) in relation to PCl is abnormal with 7em. (* = anus) (pb =perineal body) the development of an enterocele. An enterocele crease. MRI has shown that these changes in is the descent of peritoneal fat, sigmoid colon, or outer shape are the result of a tremendous elon- small bowel within the perineal sac down to the gation of the PFMs and the anococcygeal liga- perineum, between the rectum and vagina . Such ment (Fig. 2.7.11, A and B). an enterocele can bulge or evert the posterior vaginal wall, similar to a rectocele. It can also Significance ofDynamic MRI ofthe evert the anterior rectal wall into or out of the anal canal. MRI is the method of choice to dif- Pelvic Floor ferentiate if prolapse of the posterior vaginal wall is caused by a rectocele, an enterocele, or both Dynamic MRI is a method to quantify the (rectocele first; enterocele after defecation). laxity and descent of the pelvic floor and to depict abnormal behavior of the pelvic organs Laxity of the pelvic floor can cause a balloon- during strain and contraction. MRI is of ing of the perineum, thus, effacing the gluteal
154 T. Treumann et al. importance for pelvic organ prolapse and 6. Tunn R, Paris S, Fischer W, et al. Static magnetic dysfunctional defecation. resonance imaging of the pelvic floor muscle mor- phology in women with stress urinary inconti- As far as the anterior compartment is con- nence and pelvic prolapse. Neurourol Urodyn . cerned, MRI and ultrasound findings are similar. 1998;17:579-589. In the posterior compartment, MRI is superior to clinical evaluation and ultrasound in the detec- 7. Huddleston HT, Dunnihoo DR, Huddleston PM, tion and differentiation of rectoceles and entero- et al. Magnetic resonance imaging of defects in celes, causing a bulge of the posterior vaginal DeLancey's vaginal support levels I, II, and III. wall. It has to be kept in mind, however, that the Am} Obstet Gynecol. 1995;172:1778-1782. hernial sac can contain structures that are not located in the midline. To get these structures 8. Klutke C, Golomb }, Barbaric Z, et al. The anatomy into the images, additional planes (transverse, of stress incontinence: magnetic resonance imag- coronal) are required. However, this is not part ing of the female bladder neck and urethra. }Uro!. of the standard investigation protocol. Some- 1990;143:563-566. times, the final answer is given only during surgery. For rectal intussusception, MRI is the 9. Tunn R, Schaer G, Peschers U, Bader W, Gauruder only imaging method for detection. For rectal A, Hanzal E, Koelbl H, Koelle D, Perucchini D, prolapse, MRI can be used to differentiate rectal Petri E, Riss P, Schuessler B, Viereck V. Updated mucosal prolapse from rectal wall prolapse. recommendations on ultrasonography in urogy- Mobility of the coccyx can be assessed by MRI, necology. Int Urogynecol I Pelvic Floor Dysfunct. but the role of the coccyx function and dysfunc- 2005;16(3):236-241. tion of the pelvic floor is not quite clear. The coccyx probably does not playa major role. 10. McDonald CM, Carter GT, Fritz RC, et a!. Mag- netic resonance imaging of denervated muscle: References comparison to electromyography. Muscle Nerve. 2000;23:1431-1434. 1. Tress BM, Brant-Zawadski M. Nuclear magnetic resonance imaging. Basic principles. Med } Aust. 11. DeLancey}O. Structural support of the urethra as 1985;142:21-24 . it relates to stress urinary incontinence: the hammock hypothesis. Am I Obstet Gyneco!. 1994; 2. Tunn R, DeLancey JO, Howard D, et a!. Anatomic 170:1713-1720. variations in the levator ani muscle, endopelvic fascia, and urethra in nulliparas evaluated by 12. Petros PE, Ulmsten U. An integral theory of female magnetic resonance imaging. Am}Obstet Gyneco!. urinary incontinence. Experimental and clinical 2003;188:116-121. considerations. Acta Obstet Gynecol Scand 1990; 153:7-31. 3. Tunn R, DeLancey TO, Howard D,et al. MRimaging of levator an i muscle recovery following vaginal 13. Lienemann A, Fischer T. Functional imaging delivery. Int Urogynecol [, 1999;10: 300-307. of the pelvic floor. Eur J Radio!. 2003;47:117- 122. 4. Fleckenstein }L, Watumull D, Conner KE, et al. Denervated human skeletal muscle: MR imaging 14. Bertschinger KM, Hetzer FH, Roos }E, et a!. evaluation. RadioI.1993;87:213-218. Dynamic MR imaging of the pelvic floor per- formed with the patient sitting in an open-magnet 5. De Smet AA. Magnetic resonance findings in skel- unit versus with patient supine in a closed-magnet etal muscle tears . Skeletal Radiol. 1993;22:479- unit. Radio!. 2002;223:501-508. 484. 15. Stoker }, Halligan S, Bartram C. Pelvic floor imaging. A review. Radio!. 2001;218:621-641. 16. Baessler K, Schussler B. The depth of the pouch of Douglas in nulliparous and parous women without genital prolapse and in patients with genital prolapse. Am I Obstet Gyneco!. 2000;182: 540-544.
2.8 Electrophysiology Clare J. Fowler and David B. Vodusek Key Message muscles necessary to maintain posture arise from the vestibular nuclei and reticular forma- Nerve and muscle cells produce and conduct tion. More detailed information about general electrical activity. Two main types of investiga- motor control can be found in a number of stan- tions are used - electromyograph, to detect dard physiotherapy texts. Motor units of muscles signals for striated muscle, and conduction that comprise the pelvic floor are tonically active. studies, which employ electrical, magnetic, and Unlike most other skeletal muscles, this activity mechanical stimuli to detect sensory, motor, and cannot be voluntarily suppressed, except as part reflex responses of the nervous system. These of the coordinated process of micturition or def- tests may be used to investigate patients with ecation, which requires relaxation of the pelvic central and peripheral nerve lesions affecting floor. the urogenital anal region and for research purposes. As explained in preceding chapters, the muscles of the pelvic floor include those that Introduction form its base and provide general support to the pelvic organs, i.e., the pubococcygeus and levator Movement is achieved by activation of the motor ani and, as separate structures, the striated units in muscles. A motor unit is defined as all muscle of the urethral and anal sphincters. It muscle fibers within an anatomical muscle that seems likely, although is by no mean s proven, are innervated by the same motor axon. The that whereas the muscles that provide pelvic essential components of the motor units are organ support are activated in response to pos- shown in Figure 2.8.1. Coordinated muscle activ- tural changes and changes in pressure within the ity, voluntary activation of a muscle, and the abdominal cavity, control of the sphincters is resting tone of the muscle are determined by the more intimately related to the function of the pattern of activations of motor neurons, which lie bladder and rectum, respectively. in the anterior horn of the spinal cord. Activation results from descending spinal inpu t and seg- Striated Muscle Activity and mental spinal reflexes. Electromyography Skilled voluntary movement, as needed to Urethral Sphincter perform tasks which requ ire manual dexterity need individual motor units to be activated in a This small circular muscle surrounding the highly refined pattern generated by the motor urethra has a critical role in urinary continence. cortex. In contrast, patterns of activation of axial Studies in experimental animals and humans 155
156 (.J.Fowler and 0.8. Vodusek FIGURE 2.8.1. Schematic representation ofa motor unit showing maneuver\" in patients and volunteers, but it is, of themotor cell body, its myelinated axon in the peripheral nerve, course, by this mechanism that incont inence may and muscle fibers, which are all innervated by thatmotor axon. be avoided if urgency is experienced. The pathway involved requires connections between the motor cortex and sacral cord and is therefore often affected in patients who have spinal cord disease. It is, however, available to patients with idio- pathic detrusor overactivity, i.e., an overactive bladder in the absence of neurological disease. Striated Anal Sphincter have shown that activity in this muscle increases The neural processes involved in fecal continence with increasing bladder distension. This is part have been studied even less than those of bladder of the \"guarding reflex,\" which is organized at a control. However, the same pattern of tonic acti- spinal level. Increases in motor unit activation vation during the filling phase is thought to occur with sudden rises in abdominal pressure, occur, with suppression of activity at the onset of such as occur during coughing, sneezing, etc. defecation . Voiding is achieved by the activation of a group Increases in motor unit activity in the sphinc- of neurons that lie in the dorsal part of the pons ter are, again, crucial in maintaining fecal or that send inhibitory input to Onuf's nucleus in flatal continence, and it seems likely that activa- the sacral spinal cord, the nucleus formed by the tion of this muscle has an inhibitory effect on anterior horn cells that innervate the urethral rectal contraction. sphincter. Cessation of motor unit activity in the sphincter is the first recordable event of volun- Methods ofRecording EMG Activity tary micturition, and th is is followed some from the Pelvic Floor seconds later by a contraction of the detrusor smooth muscle. This coordinated sphincter The method preferred by electromyographers for relaxation and detrusor contraction depends on recording muscle motor unit activity is usually intact spinal cord connections between the pons the concentric needle electrode (CNE). In pre- and the sacral part of the cord (Fig. 2.8.2). If vious years, some very specialized recordings spinal disease disrupts these connections, sacral were made using single-fiber needles, but these segmental reflexes emerge, which cause the are no longer commonly being used. They have detrusor muscle to contract in response to low an expensive construction and therefore, non- bladder volumes, i.e., detrusor overactivity. A disposable . Some approximation to the signal second feature of the spinal disruption is that the recorded by a CNE may be obtained by using synergistic behavior of the sphincter and the surface electrodes of various sorts, but the preci- bladder is lost and detrusor sphincter dyssyner- sion of what is being recorded, and the details of gia occurs, i.e., the striated urethral sphincter the electrical signal are inevitably less refined contracts when the detrusor muscle is using such devices. contracting. Concentric Needle Electrode In addition to the striated urethral sphincter's role in micturition and bladder emptying, volun- A CNE consists of a central recording wire that tary contraction of the sphincter has a powerful forms the core of an outer cannula. As with inhibitory effect on detrusor contraction. This all electrophysiological recordings, a measured effect has been studied little in animals because change in voltage is recorded between an active of the obvious difficulty of experimental design, and a reference electrode. In the CNE, the central but there is some neurophysiological data point- wire forms the active electrode and the cannula ing to an inhibitory influence. Curiously, there have been few studies of this \"pro continence
2.8. Electrophysiology 157 + satellit e spike part duration 100 ~v IE------s--l;o--w p--a--r,t,.-d--u,--r-a--:t-i,o..n-----~ o 5 10 15 20 ms +turn • phase FIGURE 2.8.2. Component phases ofmotor unit potential (bottom) recorded with a CNE (top). The spike ofthemotor unit is produced by themuscle fibers closest totheelectrode, whereas thelate phases result from activity in more distant fibers. forms the reference. The distal end of this com- pected cauda equina lesions, and the innervation bination is sharpened to a bevel tip to facilitate of those muscles, differential diagnosis of various its insertion into tissue, and the recordings are forms of Parkinsonism. Used in these circum- made from a hemispherical recording volume stances, it is the prolongation and enlargement with a diameter of 0.5mm . The CNE will, there- of motor units that is being sought. These are, fore, be recording the extracellular currents of in fact, the consequence of reinnervation and approximately 20-30 muscle fibers, and because provide no evidence about the extent of denerva- each of these are part of separate motor units, tion that has occurred. Using a CNE, the only when a CNE is used to record from the striated clue to the extent of a denervating injury is the muscle of either sphincter approximately five or reduction in the number of firing motor units six motor units are found firing tonically while at that can be reflexively or voluntarily recruited. rest. With voluntary recruitment this number Unfortunately, this is inevitably a somewhat sub- increases, which also happens if the subject jective assessment, although the sophisticated coughs, sneezes, etc. The ongoing activity in software that exists in some EMG machines these muscles precludes the possibility of detect- attempts to provide a statistical and more objec- ing spontaneous fibrillations, which is the hall- tive approach. For the physiotherapist's assess- mark of denervation in other skeletal muscles. ment of the pelvic floor, the only advantage to be gained from using a concentric needle electrode In the clinical neurophysiology laboratory, the would be the certainty of knowing precisely electromyographer would inspect the configura- which muscle information is being recorded tion of individual motor units, a procedure easily from. This information is lost when using surface performed using a CNE in conjunction with an electrodes, but the design of the CNE has been EMGmachine that has a \"trigger and delay line.\" such as to optimize its \"in-out\" insertion for Captured motor units are stored, and their ampli- what the electromyographers call \"sampling\" a tude, duration, and number of phase reversals muscle, and not long-term recording situations. (polyphasicity) measured up in some detail (Fig. 2.8.2), either by setting cursors or, nowadays, by Hook Wire Electrodes using automated analysis techniques. Individual motor unit analysis of the urethral, but more A recording system which combines the commonly of the anal, sphincter is carried out for precision for a selected site together with the diagnostic purposes in the investigation of sus-
158 ('J. Fowler and0.8.Vodusek W R:50IlV.ldiv. W L:50IlV.ldiv. tA Voluntary contraction FIGURE 2.8.3. A kinesiological EMG recording with hook wire coccygeus muscle, and recruitment of motor units is brisk and electrodes from the right and left pubococcygeus muscle in a relatively short lasting. Such activity pattern has been called female. The detection sitein theright muscle detects continuous \"phasic\" (on theleft). Such patterns can berecorded in a normal firing ofmotor unitpotentials during relaxation (\"tonic\" activity). pubococcygeus muscle atdifferent detection sites and,in thecase Also, ontheright, a more prolonged recruitment ofmotor units presented, donot signify pathology. Akinesiological EMG record- has occurred. Such pelvic floor muscle activity pattern has been ing ofa pathological pattern ofactivity ofpubococcygeus muscles called \"tonic\" (on the right). There is no firing of motor units can beobserved in Figure 1.2.9. during relaxation attheparticular detection site in theleft pubo- possibility of making long-term recordings is the area and furthermore, the soft tissues, i.e., con- \"hook wire electrode.\" The essential part of this nective tissue, fat, and skin, between the muscle recording system consists of a twisted pair of and the electrode, may significantly attenuate the coated wires with exposed tips shaped into a amplitude of the signal. Thus, with a CNE the hook. These are inserted into the particular amplitude of the EMG activity from the levator muscle to be studied through a hollow core needle ani might be expected to be up to 500mV, but and the needle then withdrawn. The hook is an amplitude of one tenth of that would be retained in the muscle for long-term recordings considered \"good\" if recorded using a surface and is removed at the end of the recordings by electrode. tugging gently. The difficulty of using this type of electrode is that, whereas with a CNE the posi- The advantages of surface electrode recordings tion of the electrode can be adjusted to give the are that the attachment of the electrodes is pain best EMG signal by listening over the audio free and that movement is less likely to dislodge output system of the recording machine, this is the recording position. However, surface elec- not possible with the hook wire electrodes trodes will pick up EMG activity from muscles because the quality of the signal can only be distant from the one being studied, the amplitude examined when the ensheathing needle has been of the signal may be low, and the contribution of removed, and at that point little adjustment of the interference considerable. These limitations not- wires is possible. Notwithstanding these difficul- withstanding, this is the type of recording elec- ties, some groups have succeeded in making very trode most commonly used in physiotherapy useful \"kinesiological\" recordings from the pelvic practice when recording from pelvic floor floor and shown asymmetries in activity at rest structures. and on coughing in women with stress inconti- nence (Fig. 2.8.3). An important practical aspect of using these recording devices is that the raw recording should Surface Electrodes be carefully inspected for the veracity of its EMG content before any subsequent analysis is per- The principle of recording EMG with surface formed (Fig. 2.8.4). Ideally an audio output of the electrodes is that the active electrode is placed signal should be obtained so that any recogniz- over the main body of the muscle and the refer- able electrical interference can be minimized. ence is placed over the tendon insertion of that When what is thought to be a good EMGsignal is muscle. A surface electrode has a large pick up obtained, the subject should be asked to volun- tarily contract, and an increase in ongoing EMG activity listened for. Because the EMG signal is
2.8. Electrophysiology 159 A vagina, with a th ird electrode placed over a bony point to act as a ground electrode. In an B effort to increase the proximity of the surface electrode to a structure deeper within the pelvis, c such as the urethral or anal sphincter, especially devices on which the recording electrode is -.J 100IJV mounted have been made. In particular, there is a commercially available sponge electrode that 80rns can be used to record from the urethral sphinc- ter, a range of device probes that are used to FIGURE 2.8.4. EMG recording withsurface electrodes from rectus record activity from the pubococcygeus muscles abdominis (A)well separated, artifact free recording, (8) record- in women , and a variety of anal probes that are ingelectrodes poorly placed, (e) poor EMG signal withhigh mains inserted into the anal canal to record activity interference content. from the anal sphincter and puborectalis muscle in men and women. recorded as a waveform, cont inuously crossing from positive to negative, and the need in muscle Other Neurophysiological building sessions is often only to look at the level Investigations of increase in the signal with voluntary activa- tion, various online analysis facilities are avail- There are various other neurophysiological tests able, which perform rectification, i.e., converting that can be performed in the laboratory, which all signals to positive, and integration of the orig- are somet imes referred to as «electrodiagnostic inal EMGsignal. Although th is has the advantage tests\" or more inaccurately «EMG\" (because that that a single line may be watched and observed term should properly be reserved for electromyo- to go up when there is an increase in muscle graphic recordings). The other tests are reflex activity, if the fundamental signal is of poor studies, nerve conduction studies, or evoked quality this may not be recognized. Poorly potentials. attached recording electrodes, which allow high amplitude, mains interference may also display a Reflex Studies rise in the integrated signal if, during a contrac- tion, the configuration of the electrodes moves Reflex studies look at the timing of a muscle and the interference component increases. response after an electrical stimulation of skin or a nerve. Specifically, in the pelvic region, where there are many physiological reflexes, two have been studied; the bulbocavernous and the anal reflex. Each requires a recording system to pick up the respective muscle response, and stimuli are given to the urogenital area . A reflex analo- gous to the bulbocavernosus in men is not easily recorded in women, but recordings from the anal sphincter are more robust. Types ofSurface Electrodes Nerve Conduction Studies Sticky pads incorporating a small metal surface The principle of nerve conduction studies is that are easily applied to the skin, and many papers an electrical pulse is given at a point along a have been published on the use of such electrodes ner ve, and a response is recorded either from a attached to either side of the anal sphincter or muscle which that nerve innervates or from the nerve itself, from some distance away. The
160 c.J. Fowler and D.8. Vodusek recordings that are taken are referred to as \"com- Pudendal Motor Latency pound muscle action potentials\" or \"sensor action potentials,\" respectively. Based on the established clinical value of conduc- tion studies to detect the entrapment condition If a motor nerve is stimulated at two points, of carpal tunnel syndrome, it was proposed that giving a proximal and distal motor latency, and stimulation of the pudendal nerve at the level of the figures subtracted from one another (so that the ischial spine and recording from muscles it slowing of the nerve in its distal parts where it innervates, such as the pubococcygeus or the enters the muscle are removed from the sum) the urethral or anal sphincter, would be of value in figure left is known as the \"conduction time.\" detecting nerve damage following childbirth. This, divided into the measured distance between Theoretically, however, there have always been the two stimulation sites, gives the measured arguments against this test as a means of detect- conduction velocity of that nerve segment in ing significant pelvic floor weakness. Chief meters per second . However, the conduction amongst these was the concern that a prolonga- velocity of a nerve is not as valuable as might be tion of latency does not give an indication of the supposed. This is because, unless any pathology extent of muscle denervation. The investigation affecting the nerve causes a loss of the fastest that might have reflected axonal loss was the conducting axons, conduction velocity may be compound muscle action potential recorded reduced by very little, possibly by as little as 10%, either from the urethral sphincter or pelvic floor despite severe nerve fall out and muscle weak- muscles. Initial reports did not include any data ness. The real value of the conduction times of on amplitude of the recorded compound muscle nerves is in detecting either generalized or focal action potentials and, unfortunately, more recent regions of demyelination. Demyelination is the attempts to design recording electrodes that process whereby the axon of the nerve remains in could pick up well from these muscles have not tact, but its insulating sheath of concentric wraps been successful, and the recorded amplitudes are of myelin is disrupted, leading to an impairment often only a few microvolts. Although it seems of the physiological salutatory conduction of that likely that stretching of the pudendal nerve nerve. If there is uniform demyelination along occurs with parturition, attempts to demonstrate the whole nerve, as occurs in an inherited demy- this using pudendal motor latency have not elinating neuropathy, the measured conduction proved useful, and measurement of this conduc- velocity can be reduced from the normal range of tion figure is certainly not used in clinical labo - 50-60 m/sec down to 20-10 m/sec. If, however, ratories to investigate women with suspected impulses still manage to get through, albeit stress incontinence, nor is it now recommended slowly, the clinical deficit associated with this as a research investigation. laboratory-measured, slow-conduction velocity can be quite minimal. Evoked Potentials Regions of focal demyelination occur where a Evoked potentials are the electrical response nerve is entrapped, most famously at the carpal recorded from neural tissue, either the spinal tunnel of the wrist. In this condition, stimulation cord or cortical surface, in response to repeated of the median nerve above the wrist , while record- peripheral stimulation. First introduced to test ing from a muscle of the thumb, the abductor conduction in the optic nerves, the visual- pollicis brevis, will demonstrate focal slowing of evoked response is recorded with scalp electrodes conduction velocity. It should be noted, however, over the visual cortex while the subject looks that the degree of slowing is not likely to correlate at a checked board on which the black and with the weakness of the muscle. white squares alternate. Critical in detecting the cerebral response is the process of Of greater possible clinical relevance, but \"averaging,\" whereby electroencephalographic unfortunately more subject to technical variabil- activity time locked to the onset of the stimulus ity, is the amplitude of the compound muscle action potential because this envelope contains a summation of all the motor units that can be activated by electrical stimulation of the nerve.
2.8. Electrophysiology 161 becomes more pronounced and background potential is technically easy to record, it clinical activity from the random ongoing waveforms is value in detecting a spinal cord deficit can be diminished. equally well accomplished by recording the stan- dard tibial evoked responses - it is rare to find an This same principle of averaging the cortical abnormality of the former without the latter also signal in response to a repeated stimulus such as being abnormal. an electrical pulse to a peripheral nerve is the basis of the somatosensory evoked potentials Conclusion (SSEPs). Although stimulation of the median nerve at the wrist or tibial nerve at the ankle Over the course of many years, various neuro- are the SSEPs most commonly performed in physiological techniques have been developed clinical neurophysiological laboratories, it is that have quite quickly been transferred to the also possible to record an SSEP after stimulation investigation of the pelvic floor. Only a few of of the pudendal nerve. For this the subject these have been shown to be of enduring value, holds the stimulator on the dorsal nerve of whereas some, such as single-fiber EMG and use the clitoris or penis and electrical stimuli of magnetic stimulation, are no longer recom- given at an intensity of two to three times that of mended even as research techniques. For the threshold for sensation, i.e., a non-painful investigation of neurological patients with pelvic intensity. organ complaints some of the more complex investigations may still be used but for physio- Although when first introduced it was hoped therapy practice - both clinical and research - that this recording would provide insight into the surface EMG recordings are likely to continue to afferent innervation of the pelvis, this has not give the best results . proved to be the case. Electrical stimulation depolarizes the largest myelinated nerve fibers Acknowledgment. We would like to thanks Prof of a sensory nerve, those which convey muscle Grace Dorey PhD, FCSP for her advice about the afferent activity or the sensory modalities oflight text. touch and vibration and does not activate those small unmyelinated nerve fibers involved in vis- ceral sensation . Although the pudendal evoked
2.9 Outcome Measures in Pelvic Floor Rehabilitation Kate H. Moore and Emmanuel Karantanis Introduction How to\"Validate\" an Outcome Measure Throughout this textbook, many different mea- sures are used to evaluate the pelvic floor and First, it is useful to briefly define what is meant urinary or fecal incontinence. In this chapter, by \"validation.\" The design of symptom score or those measures that are also suitable for evaluat- questionnaire is not a simple process, and the ing posttreatment response , or \"outcome,\" are development of a physical test (e.g. perineome- considered. In the past 3-4 decades, numerous try) for use as an outcome measure also requires tests, scoring systems, and quality-of-life instru- considerable work. ments have been created . Unfortunately many of these tests have not been formally validated as The process of validation for symptom scores outcome measures. Therefore they may not give and quality of life tests requires one to demon- an accurate picture of the \"quantity\" of a patient's strate validity, reliability, and responsiveness to response to treatment. Also, when many different change after treatment. These items must also be outcome measures are used to gauge response to demonstrated for tests of physical function, but any treatment (by different authors) , it is almost some differences in methods occur between psy- impossible to compare results. chometric tests and physical tests. This chapter gives a brief overview of some of Validity refers to whether the test measures the early nonvalidated outcome measures that what it is supposed to measure. There are three are still in use, and then describes more recent main aspects : tests that have been fully validated. The system of categorization used is that of the Standardiza- 1. Content/face validity is the assessment of tion Committee of the International Continence whether a questionnaire makes sense to the Society (rCS),! which recommends that there patients and clinicians, i.e. that it is understand- should be five main groups, or \"domains\" of able, unambiguous, and clinically sensible. outcome measures: Construct validity involves assessing how the questionnaire performs in a range of setting and 1. Patient's observations (symptoms) patient groups . One example is differentiating 2. Quantification of symptoms (e.g. urine loss on between patient groups, such as hospital patients and individuals in the community. Criterion diary or pad test) validity describes how well a questionnaire 3. Physician's observations (anatomical and correlates with a \"gold standard\" measure that already exists. This \"criterion validity\" also is functional e.g. perineometry, and compliance important for tests of physical function, e.g. with treatment) leakage, on ultrasound of the bladder neck 4. Quality of life measures 5. Socioeconomic evaluations. 162
2.9. Outcome Measures in Pelvic Floor Rehabilitation 163 may need to be validated against leakage on TABLE 2.9.1. Three point scales videourodynamics. Stamey Grading 2. The reliability of a test refers to its ability to I Leak withstressful activities ego cough. sneeze etc measure quantities reproducibly. There are two II Leak with minimal activities egowalk/standing up aspects: (a) internal consistency and (b) repro- III Leak at all times, all activities irrespective ofposition ducibility. Internal consistency refers to the Ingelmann - Sundberg Scale extent to which items within a questionnaire are I Incontinence only when coughing, sneezing, orlifting heavy consistent with each other. It can be assessed by statistical techniques such as item-total correla- objects tion or Cronbach's alpha. Reproducibility is an II Incontinence during daily activities ego rising from a chair, or important concept for both questionnaires and physical tests that measure outcome, as one must fast walking demonstrate that responses are stable over a III Dripping incontinence intheupright position short period of time in a pretreatment sample (i.e, by giving the same test to respondents 2-6 never validated, yet they are still commonly used weeks apart, before treatment starts). Reproduc- today. For example, Stamey scores are commonly ibility is assessed by using analysis of variance used in studies assessing urethral bulking (to find the standard deviation for repeated mea- agents'< because the score continues to be stipu- surements), or by determining the intraclass cor- lated as an outcome measure for research by the relation to determine variability between and US Food and Drug Administration, whereas within subjects, or by using the Bland-Altman several European groups continue to use the method to derive the limits of agreement.2,3 Many Ingelmann-Sundberg Scale.\" studies of test-retest reliability quote the correla- tion coefficient between the first and second test, The Lagro-Ianssen 12-point score comprises 4 but this is not a correct measure of reliability categories which each have a score of 1-3. These because two tests of the same measure will gener- comprise frequency of urine loss (weekly, more ally correlate (or \"co-relate\") to a large degree. than weekly, daily), amount of urine loss (drops, Correlation between two tests does not measure a little, a lot), use of pads (none, occasionally, the degree of variation between the two tests. most of the time) and effect upon lifestyle (none, some, a 10t).9The score is used to define mild (4- 3. The responsiveness of a test describes its 6), moderate (7-9), and severe incontinence (10- response to change after treatment. This is usually 12). Although studies of repeatability are not done either by measuring effect sizes in random- available, it is interesting that the terms used in ized trials, or by analyses of covariance. There- this 1991 score are very similar to the more recent fore in order for a questionnaire to be fully lSI and ICIQ-SF, which are descibed in the fol- validated and \"robust,\" multiple experiments lowing sections. assessing all of the aforementioned components must be undertaken. The Incontinence Severity Index was devel- oped by Sandvik et al.\" It is a very short measure- Patient Symptom Scores as ment tool, having only two items. The responses Outcome Measures for the first and second question are multiplied together to give the total score a range of 0 to 8 (Table 2.9.2). TABLE 2.9.2. The incontinence severity index In the 1970s, before the advent of validated con- How often isurineleakage experienced? tinence scores, grading systems were developed Never = 0 to measure the severity of incontinence. These 1toseveral times a month = 2 were \"doctor controlled,\" with the doctor making the final impression as to what the response 1 toseveral times per week =3 should be. Popular formats included the Stamey grading system' and the Ingelmann-Sundberg Every day and/or night = 4 Scale.' These 3-point scales (Table 2.9.1) were How much urineislosteachtime? Afew drops = 1 Alittle = 1 More = 2
164 K.H. Moore and E. Karantanis ITJ ITJITJITIJ tcic-sr DD DO DO Initial number CONFIDENTIAL DAY MONTH YEAR Today's date Many people leak urine some of the time. We are trying to find out how many people leak urine, and how much this bothers them . We would be grateful if you could answer the following questions , think ing about how you have been, on average, over the PAST FOUR WEEKS . 1 Please write in your date of birth: DD DD DD DAY MONTH YEAR 2 Are you (tick one): D'Female DMale 3 How often do you leak urine? (Tick one box) Dnever Dabout once a week or less often 0 Dtwo or three times a week 1 Dabout once a day 2 Dseveral times a day 3 4 0all the time 5 4 We would like to know how much urine you think leaks. How much urine do you usually leak (whether you wear protection or not)? (Tick one box) Dnone Da small amou,:,t 0 0a moderate amount 2 4 0a large amount 6 5 Overall, how much does leaking urine interfere with your everyday life? Please ring a number between 0 (not at all) and 10 (a great deal) o 2 3 4 5 6 7 8 9 10 a great deal not at all D DICIQ score: sum scores 3+4+5 6 When does urine leak? (Please tick all that apply to you) 0never - urine does not leak 0leaks before you can get to the toilet 0leaks when you cough or sneeze 0leaks when you are asleep 0leaks when you are physically activelexercising Dleaks when you have finished urinating and are dressed Dleaks for no obvious reason Dleaks all the time Thank you very much for answering these questions. Copyright@ \"Icia Group\" FIGURE 2.9.1. The ICIQ-SFQuestionnaire.
2.9. Outcome Measures inPelvic Floor Rehabilitation 165 Severity on a 48-hour pad test and severity of The final ICIQ comprises three scored items (Fig. 2.9.1) and an unscored self-diagnostic item. the score correlates strongly (r = 0.59; P < It allows the assessment of the prevalence, fre- quency, and perceived cause of urinary inconti- 0.001}.1l nence, and its impact on everyday life using just 3 questions on one page, producing an overall The St. George Score for urinary incontinence maximum score of 21. Women can complete the was developed to parallel the Wexner scale for questionnaire quickly and completely with low fecal incontinence (see below), It asks whether levels of missing data (mean 1.6%). patients leak with stress or with urge, whether they have damp or soaked pads, and how much It discriminates well across different groups of the leakage affects quality oflife. Each of the four individuals, indicating good construct validity. questions is then graduated by the patient as to Convergent validity was acceptable, with most how often the problem occurs (weekly, daily, items demonstrating \"moderate\" to \"strong\" more than daily, etc). The 5 subscales, thus, each agreement with other questionnaires. Reliability have 4 maximum points (total maximum 20).The testing revealed \"moderate\" to \"very good\" sta- construct validity, reliability, and responsiveness bility in test-retest analysis and a Cronbach's to change have been published,\" and its suitabil- alpha of 0.95. The ICIQ correlates strongly with ity for telephone administration of long-term follow-up has been shown.\" the 24-hour pad test (r =0.458; P =0.000}.17The The Groutz Score is not just a symptom score, test is also responsive to treatment. Because it is but combines results of a patient questionnaire very simple, yet very \"robust\" and is recom- (0, cured; 1, improved; 2, failed) along with point mended by the WHO/ ICI, it will probably become scores from the 24 hour voiding diary (0, no the gold standard in this area . leaks; 1, 1-2 leaks; 2, ~3Ieaks) and a 24-hour pad test (0, <8g; 1, 9-20 g; 2, >20g}.14 This is a very The Wexner Score for fecal incontinence was attractive scoring system because it combines the originally designed as a 20-point score concern- first 3 domains of the ICS recommendations. ing 3 types of incontinence and one category for Because patients grade their degree of cure in the impact upon lifestyle, but was later modified to questionnaire, it cannot be used for baseline include a score for the need to wear a pad, the assessment , which is a minor shortcoming in sta- need to take constipating medication, or fecal tistical analysis. urgency (Table 2.9.3). The ICIQ-SF is the most recently validated The internal consistency, test-retest reliability, questionnaire. It is a symptom severity and construct validity, criterion validity, and sensi- quality of life instrument, developed under the tivity to change of the Wexner score appear to be auspices of the International Consultation on adequate.\" The score is widely used as an outcome Incontinence (ICI) and has undergone full psy- measure in North America, the United Kingdom, chometric testing.\":\" Australia, and several European countries. TABLE 2.9.3. Modified faecal incontinence score (Vaizey et a11999) Never Rarely Sometimes Weekly Daily Incontinent Solid Stool o 2 3 4 Incontinent LiquidStool o 2 3 4 Incontinentto Gas o 2 3 4 Alters lifestyle 2 3 4 o No Yes 2 Need to wear pad/plug o 2 Take constipatingmeds o 2 Unable to defer 1S min o
166 K.H. Moore and E. Karantanis Quantification ofSymptoms Pad Tests Frequency ofLeakage on Bladder Diaryl The Pad Test Frequency Volume Chart The paper towel test was first published by Miller Moving away from scores and questionnaires, et al.2S This study provided the protocol and we now consider tests that actually measure formula for calculating the degree of leakage leakage severity. The most commonly used is made on a paper towel folded in 3 layers (placed the bladder chart. This is a generic term used against the perineum), based on the diameter of to indicate several types of records: the micturi- the patch formed by the leak, when certain pro- tion chart, which only requires the patient to vocative maneuvers are performed with a com- document times of voiding and incontinence epi- fortably full bladder. The same authors\" later sodes; the frequency volume chart (FVC), which found that the test failed to correlate with other also requires patients to record their fluid intake measures of severity, and concluded that the test and their voided volumes, and the changing of was inaccurate. pads; and the urinary diary, which includes the details of the FVC but also includes symptoms 7-hour Pad Tests and activities at leakage episodes, including urgency, and assessment of the severity of each Sutherst\" and Walsh28 originally described the leakage episode. Although the urinary diary pro- use of perineal pads in the objective assessment vides more detail about the episodes of leakage, of urinary loss. The test procedures were then it results in poorer compliance because of the standardized,\" andafter being endorsed by the detail required.\" International Continence Society in 198830 they became a widely used outcome measure. Patients A FVC or urinary diary is a useful outcome were asked to attend with a comfortably full measure, with the simplest parameter being bladder, then drink 500ml of water over 15min, the number of leakage episodes per 24 hours. then perform a preset group of activities to One of the main debates about diaries is provoke leakage (walking and stair climbing for the degree to which a clinician can trust what 30min; standing up 10 times, coughing 10 times , a patient annotates. The quality of the in- running 1min , bending 5 times, and washing formation depends upon patient compliance, hands for 1minute). The voided volume was then which needs to be assessed with the patient measured. face-to-face. The repeatability of the l-hour pad test has Another controversy about diaries is the dura- been heavily criticized. In the mid-1980s, four tion over which they should be undertaken. groups of authors studied repeatability in small Seven-day diaries have been shown by several sample sizes (18-23 patients per study). Klarskov authors to have excellent test-retest reliability\":\", and Hald31found that the physical tasks dictated are the most sensitive and accurate, but also by the test were quite demanding, and many produce the least compliance\" . Recently, a test- patients completed them to a variable degree. retest reliability study of the seven-day voiding Lose et al.32 found wide divergence of results in diary was performed (n = 138)23 The test-retest approximately 50% of patients, which they attrib- reliability for the number of weekly incontinence uted to differing degrees of diurese during the episodes was high (r = 0.83). The correlation two tests, in accordance with Jorgensen et a1.33 between the first 3 days and the last 4 days was and Christensen et al.34 very high (r = 0.9). They concluded that a 3-day diary is an appropriate outcome measure in stress Lose et a1.3Slater assessed repeatability using incontinence. the Bland-Altman method\" in 25 incontinent women at a standardized bladder volume, but Although longer durations may be most reli- found differences of up to 24g between two test able, the ICI committee for research methodol- results. Because a large bladder volume may ogy suggested that, in most cases, a single 24-hour increase leakage,\" they improved repeatability diary is sufficient. 24 by catheterization and retrograde filling of a
2.9. Outcome Measures inPelvic Floor Rehabilitation 167 large standard volume (which appears unneces- mainly because the test requires 2 hours of careful sarily invasive). A larger (n = 56) repeatability nursing attention in the laboratory. The test does study was undertaken by Simons et al.37 Bladder not correlate with a visual analogue score of volume was standardized by repeated ultrasound severity.\" A home 2-hour pad test was investi- during natural fill, so that the test volume at the gated by Wilson et al,\" but has not been further second occasion was close to that of the first test. validated. Nevertheless, substantial variations between the two tests were found . The test-retest reliability of The 24-hour Pad Test the l-hour pad test was found to be clinically inadequate, making it unsuitable for use as an In the mid-I980s, several authors investigated 24- outcome measure. hour and 48-hour home pad tests.\":\" Women were given a set of pre-weighed pads in sealed The l-hour test also appears to be less sensitive bags, to be worn for a 24-hour or 48-hour period. than a longer test for detecting incontinence, par- Such tests are not embarrassing, and reflect ticularly in women with mild incontinencer \":\" everyday function/ provocation of incontinence. Another problem is that patients must be suffi- Several authors have demonstrated that there is ciently robust to climb stairs, lift shopping bags, no loss of accuracy by evaporation from the and jump 10 times. Consequently, many authors sealed plastic bag for durations ofn hours,\" one have adapted and modified the test, making any week,\" and two weeks.\" Thus, wet pads can be interpretation between studies impossible.\" The returned via the mail from any location. l-hour pad test also fails to correlate with other measures of severity. Theofrastos et al.\" and The 24-hour pad test has been found to be Fantl et al.\" et al. showed that the UDIIIIQ did more sensitive than the l-hour test.\" In 31 incon- not correlate with the l-hour pad test measures tinent women who underwent both tests, 13 of severity, nor did urodynamic assessment of patients were dry after the l-hour test, compared severity correlate .\" to 3 on the 24-hour test, giving a false-negative rate of 39% for the l-hour test. The l-hour and Until recently, the l-hour pad test was the only 24-hour pad test results did not correlate objective method that could be used to differenti- significantly. ate mild, moderate, and severe incontinence. The volume leaked was divided by the total volume of Normal ranges for the 24-hour pad test in the bladder at the start of the test, and the per- continent women have been controversial. Versi centage of total volume leaked was divided by the et al,50 and Mouritsen et al.51 tested 24 \"young total volume of the bladder at the start of the test. nursing and physiotherapy students\" and 25 The percentage of total volume leaked was used nursing and physiotherapy staff (median age 41) to calculate 33% centiles for the patient sample . respectively. Such young patients are not repre- This yielded definitions of \"mild\" (1-10g), \"mod- sentative of the typical age group presenting with erate\" (11-50g), and \"severe\" (>50g).31 urinary incontinence. Lose et al.\" recruited 23 continent women with a more appropriate age The 2-hour Pad Test group (34-69 years), and Ryhammer et al.52 tested 78 continent postmenopausal women, (age range The 2-hour pad test was designed by Sutherst 45-57 years). In all these studies, home kitchen et al.27 to reduce the problem of variable and scales were used to weigh the pads, with accuracy often inadequate diuresis rates that are noted of only ± 1gm. These studies gave normal values within 45min of drinking 500ml in the l-hour of between 3 and 8 grams, which seems a large test.\" In the 2-hour pad test, after emptying the amount of fluid to be tolerated by an asymptom- bladder (thus, starting at a known zero volume), atic woman . Recently, the normal values were the patient drinks 1L, and then waits for 1 hour defined in 120 women of median age 48 (IQR before commencing the same provocations given 32-60); using scales accurate to 0.1g, a median in the l-hour test. This was found to be more value of 0.3g (IQR 0.2-0.6; 95th centile 1.3g) was sensitive,\" but repeatability studies are lacking, obtained.
168 K.H. Moore and E. Karantanis Charaderization ofMild, Moderate, and Severe The measurement of PFM strength is fully described in Chapter 2.1.Measuring PFMstrength Because PFMexercises are more likely to be cura- (or power) is only one component of the assess- tive in patients with mild incontinence, and ment, which includes testing endurance, repeti- surgery is often offered to patients with severe tions, and fast contractions.56 The assessment of leakage, a pad test should be able to differentiate PFM strength is usually performed using digital severity groups and help to prognosticate the assessment, or by use of a perineometer. The outcome of treatment. Recently, mild, moderate, Oxford scoring system has become the predomi- and severe leakage were characterized as 1.3-20 g, nant grading method for digital assessment of 21-74g, and>75g per 24 hours, 53 respectively. PFM strength.57 During digital examination, the clinician asks the woman to tighten her pelvic Repeatability floor, and then assigns a score out of 5 (Table 2.1.6). The examiner must coach the patient first, The repeatability of the 24-hour pad test has been to ensure that the patient is performing the test controversial. Three studies have concluded that correctly, as Bump et al.58 has shown that patients repeatability is adequate/9,54,50 whereas one study who are simply given verbal instruction (without has disagreed.\" Fewstudies have assessed repeat- digital examination) are unable to contract the ability according to the type of urodynamic muscles correctly in 51% of cases. Without this diagnosis, and no studies have assessed the con- method, subsequent outcome testing is not tribution of activity to the repeatability of the possible. test. This is particularly relevant when consider- ing a woman who leaks once per week during Although the Oxford score has been in use sporting activities. A study of 108 women who since 1989, the test-retest reliability has only performed 7 consecutive 24-hour pad tests recently been demonstrated.59 More recently, the showed that, on repeated measures analysis of perineometer has been developed as an alterna- variance, there was no statistically significant tive measure of PFM strength. This involves the difference in mean pad weight during the 7 days vaginal insertion of a pressure-measuring device of pad testing. Over the 7 days, 51% of patients that measures vaginal pressures both at rest and did not change their severity grade at all and 18% during pelvic floor tightening. changed by 1 grade on 1 day.55 Bo et al. compared the findings of the Oxford Criterion Validity score to that of a perineometer and found no sig- nificant correlation, but the study was limited The 24-hour pad test has seldom been com- to 25 physiotherapy students.\" In contrast, pared to other measures of severity, but as men- Isherwood et al.59 found good agreement between tioned, the correlation with the ICIQ is highly the Oxford scale and perineometry in 263 women significant. with a wide age range. Similarly, Kerschan- Schindl et al.\" showed better repeatability and Anatomical and reliability with the digital examination rather Functional Observations than the perineometer. An advantage of the Oxford score over the perineometer is that an The most common anatomical and functional examining finger can detect any counterpro- parameters that have been used as an outcome ductive Valsalva or strain that patients may measure comprise the following: (a) PFMstrength perform. assessment, (b) urodynamic testing, (c) urethral pressure profile, and (d) leak-point pressures. Urodynamic Assessment These tests are all described in detail in Chapter 2.1 and 2.3, but their suitability as an outcome Urodynamics describes the laboratory investiga- measure will be summarized here. tion of incontinence. The main components are filling cystometry, the cough test at maximum bladder capacity, uroflowmetry, and determina- tion of the postvoid residual. The use of X-ray
2.9. Outcome Measures inPelvic Floor Rehabilitation 169 (fluoroscopy) at the time of urodynamics is the and Wickham method.\" or rnicrotransducers\" (see Chapter 2.3). gold standard, although more recently, transla- A major problem with UPP measurement is the bial ultrasound has been adopted to look for the lack of standardization. Recently, the ICS pub - lished a standardization report guiding future degree of funneling or the degree of bladder neck authors as to the basic requirements to be docu- mented in UPP studies.\" Clear documentation mobilit y associated with leakage on coughing. on patient position, bladder volume, maneuvers, and probe types is required by the ICS, but the Further description is given in Chapter 2.3. use of any standardized methods or techniques over others was not recommended. Two studies have shown that cystometric The UPP technique has been shown to be capacity measurement repeatability is poor. 62 63 repeatable. Using the Brown and Wickham fluid • perfusion method, Martin and Griffiths\" found agreement between 2 observations to be ±2 cm In a study of 50 women with stress incontinence H20 pressure. Meyhoff et al.\" examined the reproducibility of various parameters of the UPP symptoms who were filled to a minimum of in both consecutive observations on the same day, and 2 observations separated by 1 month. 300ml during cystometry, the cough test has The variability in same-day observations was adequate, but they noted significant variation in been shown to be repeatably posit ive and repeat- observations repeated after a l-rnonth interval. Hilton and Stanton\" analyzed the short- and ably negative.\" long-term variance of the microtip transducer UPP method and found good reliability. During urodynamic tests, many clinicians Only one study has attempted to correlate UPP classify severity of USI in women as mild, moder- results with severity on pad tests and validated questionnaires. The study showed no correlation ate, or severe. However, there is no standardized between maximal urethral closure pressure and the l-hour modified pad test, or between the UDI approach to grading severity. Thus, clinicians' and IIQ.41 assessment of the degree of leakage during cough Valsalva Leak Point Pressures is highly subjective , varies from unit to unit, and, The VLPP is defined as the minimal pressure within the bladder to cause urinary leakage in as such, is a poor outcome measure. For example, the absence of a bladder contraction.\" VLPP research regarding reproducibility is scant. A fluid in the proximal urethra can only be seen on study by Song et al.\" found VLPP is reproducible; however, the correlation coefficient was used. fluoroscopy, but is often considered evidence of Recently, Fleischmann et al.\" studied VLPP urethral sphincter incompetence. Yet, when uro- pressures in 65 women with stress incontinence. The 24-hour pad test results, the number of dynamic testing is used to judge \"cure,\" the leakage episodes on FVC, and the degree of urethral mobility did not correlate with the authors do not always state whether fluoroscopy VLPPvalue. This study disputes McGuire's earlier finding that low VLPP readings correlated was used. They may employ twin channel cys- with worse leakage. A study by Nitti and Combs\" found a strong correlation between tometry and define \"cure\" as no leakage of urine the subjective degree (SEAPI-QMN) of urinary from the external urethral meatus. The classic type I, II, and III categorization of stress incontinence on videourodynamic testing with urethral pressure measurement developed by McGuire65 does not appear to have been sub- jected to repeatability assessment and is not gen- erally regarded as an outcome measure. Only one study has correlated urodynamic severity grading with severity on the l-hour pad test. In this study, women at maximum capacity in an erect oblique position were asked to cough as hard as possible. Severity ofleakage was deter- mined arbitrarily: severe, leakage occurred on the first cough ; moderate, on the second or third cough; slight, if leak only after multiple coughs and encouragement. The study showed no sig- nificant correlation between the clinician's impression and l-hour pad test. \" Urethral Pressure Profilometry Urethral pressure profilometry (UPP) may involve the use of water-perfused catheters the Brown
170 K.H. Moore and E. Karantanis incontinence and VLPP in 51 women with stress languages. Its disadvantages are its length and incontinence. complicated scoring system. Leak-point pressure measurement has been Many other quality oflife tests have been vali- hindered by the same lack of standardization dated for use as outcome measures in male incon- seen with the UPP. The VLPP is thought to be tinence, or for patients with the overactive bladder. most accurately measured at bladder volumes of These are not considered here, as they do not 250-300 ml,\" but this varies from study to study. directly relate to rehabilitation of the pelvic floor; The VLPP remains to be standardized regarding for further details see Donovan et al.82 catheter size, bladder volume , and the presence of cystocoele.\" In addition, the pressure record- Socioeconomic Evaluation ing at the moment of leakage is difficult to standardize. The ICS Standardization Committee recom- mends that the costs of incontinence should be The definition of high or low VLPP is not stan- an important outcome measure. If a treatment dardized. Generally, a VLPP of 60em H20 or less reduces leakage, it should also reduce the costs of is thought to represent severe leakage (\"intrinsic managing that leakage . A balance occurs when sphincteric deficiency\"),\" although this defini- the cost of the treatment is less than the pretreat- tion varies, e.g. some authors use a VLPP cut-off ment management costs, but the time frame over for ISD of <100ern H20 .78 Furthermore, there is a which all these costs are calculated is important. poor correlation between VLPP and UPP.71 For further details of economic evaluation see Hu et al.83 Quality ofLife Scores The ICS recommends that incontinence costs In the last decade , attempts have been made to be gathered in seven aspects: standardize and validate self-completed ques- tionnaires as instruments assessing subjective 1. The costs of clinicians' time and services. severity and quality of life associated with 2. The costs of laboratory tests and imaging incontinence. studies. The Urogenital Distress Inventory (UDI) and 3. Expenses for procedures and medications. the Incontinence Impact Questionnaire (IIQ) 4. The costs of disposable and reusable pads, were developed by Shumaker et al.\" to assess the impact of urinary incontinence symptoms on undergarments, bed protectors, etc. quality of life for women . The original forms of 5. The costs of managing side effects and adverse the IIQ and UDI had 30 and 19items, respectively. Later work by Uebersax et al.\" created a 7-item events arising from treatment (e.g., de novo version of the IIQ and a 6-item version of the UDI. detrusor overactivity after bladder neck These are now widely used in both clinical and surgery). research applications. 6. The costs of travel to obtain treatment. 7. The loss of wages from receiving care or The Kings Health Questionnaire,was first surgery. developed at Kings College Hospital London by Kelleher and Cardozo and published in 1997.81 It These items have been assembled into a nurse- has 21 items and was designed to measure symp- toms and quality of life for men and women with administered cost index, for which the construct urinary incontinence. The 21 items are distrib- uted to form 8 domains that are scored between validity, test-retest reliability, and responsive- o and 100, with 100 indicating a greater impact ness to treatment change have been published on quality of life. Domains include sociallimita- (the Dowell-Bryant Incontinence Cost Index 84 8S . tions and sexual function. It was developed in the •) United Kingdom, making it most appropriate for that population, but has been translated to many The ICS recommends that such measurements of cost be built into the design of any new therapeu- tic trial. Full economic analysis of the efficacy of treat- ment usually involves use of a specific type of quality oflife test that allows one to calculate the benefit in terms of Quality of LifeYears (or QALY). For more details see Hu et al.83
2.9. Outcome Measures inPelvic Floor Rehabilitation 171 Conclusion 12. Blackwell AL, Yoong W, Moore KH. Criterion validity, test retest reliability and sensitivity to When reporting the success of any new treat- change of the St. George Urinary Incontinence ment, fully validated objective measures should Score . Br J Urol Int. 2004;93:331-335. be employed. Clinicians should not \"create\" a new outcome test unless they are prepared to 13. Moore KH, O'Sullivan RJ, Simons A, et al. Ran- validate it thoroughly. Our common research domised controlled trial of nurse cont inence interests would be best served by choosing vali- advisor therapy compared with standard urogyn- dated outcome measure at the start of any inter- aecology regimen for conservative incontinence vention tr ial. treatment: efficacy, costs and two year follow up. BJOG. 2003;110:649- 657. References 14. Groutz A, Blaivas JG, Rosenthal JE. A simplified 1. Lose G, Fantl JA, Victor A, et al. Outcome mea- urinary incontinence score for the evaluation of sures for research in adult women with symptoms treatmentoutcomes.NeurouroIUrodyn.2000;19:127- of lower urinary tract dysfunction. Neurourol 135. Urodyn. 1998;17:255-262. 15. Donovan JL, Badia X, Corcos J, et al. Symptom and 2. Karantanis E, O'Sullivan R, Moore KH. The 24- quality of life assessment. In : Abrams P, Cardozo hour pad test in continent women and men : L, Khoury S, Wein A, editors. Incontinence, normal values and cyclical alterations. Br J Obstet volume I, second edition. Bristol: Health Publica- Gynaecol. 2003;110:567-571. tion, Ltd.; 2002:269-316 . 3. Bland JM, Altman DG. Statistical methods for 16. Avery K, Donovan J, Peters TJ, et al. ICIQ: A brief assessing agreement between two methods of clinical measurement. Lancet. 1986;1:307-310. and robust measure for evaluating the symptoms and impact of urinary incontinence. Neurourol 4. Stamey T. Urinary incontinence in the female . Urodyn. 2004;23:322-330 . Campbells Urolog y, 4th ed. Philadelphia: WB 17. Karantan is E, Fynes M, Moore KH, et al. Compari- Saunders Co.; 1979:2272-2293. son of the ICIQ-SF and 24-hour pad test with other measures for evaluating the severity of urody- 5. Ingelmann-Sundberg A. Uri n inkont inens hos namic stress incontinence. Int Urog ynecol J. kvinnan. Nord Med. 1953;50:1149-1152. 2004;15:111-116. 18. Vaizey C, Garapeti E, Cahill 1, et al. Prospective 6. Bent A, Dmochowski RR, Herschorn S, et al. Eval- comparison of faecal incontinence grading uation of Uryx versus contigen as periurethral systems. Gut. 1999;44:77-80. bulking agents in female stress incontinence: a 19. Groutz A, Blaivas JG, Chaikin DC, et al. Non inva- mulitcenter random ized controlled study. Int sive outcome mea sures of urinary incontinence Urogynecol J Pelvic Floor Dysfunct. 2002;13:S24. and lower ur inary tract symptoms: a multicenter study of micturition diary and pad tests. J Urol. 7. Sand PK, Dmochowski RR. Clinical experience 2000;164:698-701. with coaptite urological bulking agent. Int Urogy- 20. Locher JL, Goode PS, Roth DL, et al. Reliability necol J Pelvic Floor Dysfunct. 2000;13:S20. assessment of the bladder diary for urinary incon- tinence in older women. J Gerontol A Bioi Sci Med 8. Soulie R. Bladder suspension by retropubic endos- Sci. 2001;56:M32-M35. copy. Techniques and preliminary results (24 21. Robinson D, McClish DK, Wyman JF, et al. Com- cases). [in French] Prog Urol. 1996;6:60-69. parison between urinary diaries completed with and without intensive patient instructions. Neuro- 9. Lagro-Janssen TLM, Debruyne FMJ, Smits AJA, urol Urodyn. 1996;15:143-1488 . et al. Controlled trial of pelvic floor exercises in 22. Wyman JF, Choi SC, Harkins SW. The urinary the treatment of ur inary stress incontinence in diary in evaluation of incontinent women: a test - general practice. Br J Gen Prac. 1991;41:445-449. retest analysis. Obstet Gynecol. 1988;71:812-817. 23. Nygaa rd I, Holcomb R. Reproducibility of the 10. Sandvik H, Hunskaar S, Seim A, et al. Validation seven -day voiding diary in women with stress of a severity index in female ur inary incont inence urinary incontinence. Int Urog ynecol J Pelvic and its implementation in an epidemiological Floor Dysfunct. 2000;11:15-17. survey.JEpidemiol CommunityHealth. 1993;47:497- 24. Payne C, Van Kerrebroeck P. Research methodol- 499. ogy in urinary incontinence. In: Abrams P, Cardozo L, Khoury S, Wein A, eds. In continence. 11. Sandvik H, Seim,A, Vanvik A, et al. A severity index for epidemiological surveys offemale urinary incon- tinence: comparison with 48-hour pad-weighing tests. Neurourol Urodyn. 2000;19:137-145.
172 K.H. Moore and E. Karantanis 1 vol. Bristol: Health Publication, Ltd.; 2002: 38. Lose G, Jorgensen L, Thunedborg P.24-hour home 1047-10n pad weighing test versus l-hour ward test in the assessment of mild stress incontinence. Acta 25. Miller 1M, Ashton -Miller lA, Delancey 10. Quan- Obstet Gynecol Scand. 1989;68:211-215. tification of cough-related urine loss using the 39. Thind P, Gerstenberg TC. One-hour ward test vs paper towel test. Obstet Gynecol. 1998;91:705- 24-hour home pad weighing test in the diagnosis 709. of incontinence. Neurourol Urodyn. 1991;10:241- 245. 26. Miller 1M, Ashton-Miller lA, Carchidi LT, et al. On 40. Soroka D, Drutz HP, Glazener CM, et al. Perineal the lack of correlation between self-report and pad test in evaluating outcome of treatments for ur ine loss measured with standing provocation female incontinence: a systematic review. Int Uro- test in older stress-incontinent women . I Womens gynecol I Pelvic Floor Dysfunct. 2002;13:165-75. Health. 1999;8:157-162. 41. Theofrastous JP, Bump RC, Elser DM, et al. Cor- relation of urodynamic measures of urethral 27. Sutherst I, Brown M, Shawer M. Assessing the resistance with clinical measures of incontinence severity in women with pure genuine stress incon- severity of urinary incontinence in women by tinence. The Continence Program for Women weighing perineal pads. Lancet. 1981;1:1128- Research Group . Am J Obstet Gynecol. 1995;173: 1130. 407-412 . 28. Walsh IB, Mills GL. Measurement of urinary loss 42. Fant! JA, Harkins SW, Wyman JF, et al. Fluid loss quantitation test in women with urinary inconti- in elderly incontinent patients. A simple and accu- nence: a test-retest analysis. Obstet Gynecol. 1987; rate method. Lancet. 1981;1:1130-1131. 70:739-743. 29. Bates P, Bradley W, Glen E, et al. Fifth report on the standardisation of terminology of lower 43. Versi E, Cardozo LD. Perineal pad weighing versus urinary tract function. Bristol: International Con- videographic analysis in genuine stress inconti- tinenence Society; 1983. nence . Br J Obstet Gynaecol. 1986;93:364-366. 30. Abrams P, Blaivas IG, Stanton SL, et al. The stan- 44. Haylen BT, Frazer MI, Sutherst JR. Diuretic response to fluid load in women with urinary dardisation of terminology of lower urinary tract incontinence: optimum duration of pad test . Br J function. The International Continence Society Urol. 1998;62:331-333. Committee on Standardisation of Term inology. 45. Richmond DH, Sutherst JR, Brown MC. Quantifi- Scand I Urol Nephrol Suppl. 1988;114:5-19. cation of urine loss by weighing perineal pads. 31. Klarskov P, Hald T. Reproducibility and reliability of urinary incontinence assessment with a 60 min Observation on the exercise regimen. Br I Urol. test. Scand I Urol Nephrol. 1984;18:293-298. 1987;59:224-227. 32. Lose G, Gammelgaard I, Iorgensen T. The one- 46. Frazer MI, Haylen BT,Sutherst JR. The severity of hour pad-weighing test: Reproducibility and the urinary incontinence in women . Comparison of correlation between the test result , the start volume in the bladder and the diuresis. Neurourol subjective and objective tests. Br I Urol. 1989; Urodyn. 1986;5:17-21. 63:14-15. 33. [orgenson L, Lose G, Andersen IT. One-hour pad- 47. Wilson PD, Mason MV, Herbison GP, et al. Evalu- weighing test for objective assessment of female ation of the home pad test for quantifying incon- urinary incontinence. Obstet Gynecol. 1987;69:39- tinence. Br J Urol. 1989;64:155-157. 42. 48. Pierson CA. Assessment and quantification of 34. Christensen SJ, Colstrup H, Hertz JB, et al. Inter- urine loss in incontinent women. Nurse Pract. and intra-departmental variations of the perineal 1984;9:18-19. pad weighing test. Neurourol Uroydyn. 1986;5:23- 49. Ekelund P, Bergstrom H, Milsom I, et al. Quanti- 28. fication of urinary incontinence in elderly women 35. Lose G, Rosenkilde P, Gammelgaard J, et al. with the 48-hour pad test. Arch Gerontol Geriatr. Pad-weighing test performed with standardized 1988;7:281-287. bladder volume. Urology. 1988;32:78-80. 50. Versi E, Orrego G, Hardy E, et al. Evaluation of the 36. Jakobsen H, Kromann-Andersen B, Nielsen KK, home pad test in the investigation of female et al. Pad weighing tests with 50% or 75% bladder filling. Does it matter? Acta Obstet Gynecol Scand. urinary incontinence. Br I Obstet Gynaecol. 1996; 1993;72:377-381. 37. Simons AM, Yoong WC, Buckland S, et al. Inade- 103:162-167. quate repeatability of the one hour pad test: the 51. Mouritsen L, Berild G, Hertz J. Comparison of need for a new incontinence outcome measure. BJOG. 2001;108:315-319. different methods for quantification of urinary
2.9. Outcome Measures in Pelvic Floor Rehabilitation 173 leakage in incontinent women. Neurourol Urodyn. NR, Sterling AM (eds). Female Incontinence. New 1989;8:579-587. York: Alan R Liss; 1980. 52. Ryhammer AM, Laurberg S, Djurhuus JC, 66. Brown MC. The urethral pressure profile. Proc R Hermann AP. No relationship between subjective Soc Med. 1970;63:701. assessment of urinary incontinence and pad test 67. Hilton P, Stanton SL. Urethral pressure measure- weight gain in a random population sample of ment by microtransducer: the results in symptom- menopausal women. J Urol. 1998;159:800-803. free women and in those with genuine stress 53. O'Sullivan R, Karantanis E, Stevermuer TL, et al. incontinence. Br J Obstet Gynaecol. 1983;90:919- Definition of mild , moderate and severe inconti- 933. nence on the 24-hour pad test. Br J Obstet Gynae- 68. Lose G, Griffiths D, Hosker G, et al. Standardisa- col. 2004;ll1:859-862. tion of urethral pressure measurement: report 54. Rasmussen A, Mouritsen L, Dalgaard A, et al. from the Standardisation Sub-Committee of Twenty-four hour pad weighing test: reproducibil- the International Continence Society. Neurourol ity and dependency of activity level and fluid Urodyn . 2002;21:258-260. intake. Neurourol Urodyn. 1994;13:261-265. 69. Martin S and Griffiths DJ. Model of the female 55. Karantanis E, Allen W, Stevermuer TL, et al. The urethra: Part l-Static measurements of pressure repeatability of the 24-hour pad test. Int Urogyne- and distensibility. Med Bioi Eng. 1976;14:512-518. col J Pelvic Floor Dysfunct. 2005;16:63-68 70. MeyhoffHH, Nordl ing J, Walter S. Short and long 56. Laycock J. Clinical evaluation of the pelvic floor. term reproducibility of urethral closure pressure In Schussler J, Laycock J, Norton P, Stanton S (eds), profile parameters. Urol Res. 1979;7:269-271. Pelvic Floor Re-education, Vol 1. London: 71. McGuire EJ, Fitzpatrick CC, Wan J, et al. Clinical Springer-Verlag; 1994:42-48. assessment of urethral sphincter function. J Urol. 57. Sampselle C, Brink C, Wells T. Digital measure- 1993;150:1452-1454. ment of pelvic floor muscle strength in childbear- 72. Song JT, Rozanski TA, Belville WD. Stress leak ing women. Nurs Res. 1989;38:134-138. point pressure: a simple and reproducible method 58. Bump RC, Hurt WG, Fant! JA, et al.. Assessment utilizing a fiberoptic microtransducer. Urology. of Kegel pelvic muscle exercise performance after 1995;46:81-84. brief verbal instruction. Am J Obstet Gynecol. 73. Fleischmann N, Flisser AJ, Blaivas JG, et al. 1991;165:322-327. Sphincteric urinary incontinence: relationship of 59. Isherwood PI, Rane A. Comparative assessment of vesical leak point pressure, urethral mobility and pelvic floor strength using a perineometer and severity of incontinence. J Urol. 2003;169:999- digital examination. BJOG. 2000;107:1007-1011. 1002. 60. Bo K, Finckenhagen HB. Vaginal palpation of 74. Nitti VW, Combs AJ. Correlation of Valsalva leak pelvic floor muscle strength: inter-test reproduc- point pressure with subjective degree of stress ibility and comparison between palpation and urinary incontinence in women. J Urol. 1996;155: vaginal squeeze pressure. Acta Obstet Gynecol 281-285. Scand. 2001;80:883-887. 75. Faerber GJ, Vashi AR. Variations in Valsalva leak 61. Kerschan-Schindl K, Uher E, Wiesinger G, et al. point pressure with increasing vesical volume. Reliability of pelvic floor muscle strength mea- J Urol. 1998;159:1909-1911. surement in elderly incontinent women. Neuro- 76. Haab F, Zimmern PE, Leach GE. Female stress urol Urodyn. 2002;21:42-47. urinary incontinence due to intrinsic sphincteric 62. Mortensen S, Lose G, Thyssen H. Repeatability deficiency: recognition and management. J Urol. of cystometry and pressu re-flow parameters in 1996;156:3-17. female patients. Int Urogynecol J Pelvic Floor Dys- 77. McGuire EJ, Cespedes RD, O'Connell HE. Leak- funct . 2002;13:72-75. point pressures. Urol Clin North Am. 1996;23:253- 63. Brostrom S, Iennurn P, Lose G, et al. Short-term 262. reproducibility of cystometry and pressure-flow 78. Hsu TH, Rackley RR, Appell RA. The supine stress micturition studies in healthy women. Neurourol test: a simple method to detect urethral sphincter Urodyn . 2002;21:457-460. dysfunction. J Urol. 1999;162:460-463 . 64. Swift SE, Yoon EA. Test-retest reliability of the 79. Shumaker SA, Wyman JF, Uebersax JS, et al. cough stress test in the evaluation of urinary Health-related quality of life measures for incontinence. Obstet Gynecol. 1999;94:99-102. women with urinary incontinence: the Inconti- 65. McGuire EJ.Urodynamic findings in patients after nence Impact Questionnaire and the Urogenital failure of stres s incontinence operations. In Zinner Distress Inventory. Continence Program in
174 K.H. Moore and E. Karantanis Women (CPW) Research Group. Qual Life Res. \"Incontinence\", Eds: Abrams P, Cardozo L, Koury 1994:3:291-306. S, Wein A. Health Publications Ltd., Plymouth; 80. Uebersax JS,Wyman JF,Shumaker SA, et al. Short 2001:965-983. forms to assess life quality and symptom distress 83. Hu TW,Moore KH, Subak L, et al. \"The economics for urinary incontinence in women: the Inconti- of incontinence\". Report of World Health Organi- nence Impact Questionnaire and the Urogenital sation, Editors : Abrams P, Cardozo L, Koury S, Distress Inventory. Continence Program for Wein A. Plymouth, UK: Health Publications Ltd., Women Research Group. Neurourol Urodyn. 1995; Plymouth; 2001;14:965-983. 14:131-139. 84. Dowell CJ, Bryant CM, Moore KH et al. Calcula- 81. Kelleher CJ, Cardozo LD, Khullar V, et al. A new tion of the direct costs of urinary incontinence: questionnaire to assess the quality of life of the DBICI, a new test instrument. Br J Urol. 1999; urinary incontinent women. Br J Obstet Gynaecol. 1997;104:1374-1379 83:596-606. 82. Donovan JL, Badia X, Corcos J, et al. Symptom and Quality of Life Assessment. Report of World 85. Simons AM, Dowell CJ, Bryant CM, et al. Use of Health Organisation Consensus Conference: the Dowell Bryant incontinence cost index as a post-treatment outcome measure. Neurourol Urodyn. 2001;20:85-93.
Part III Techniques of Pelvic Floor Rehabilitation and Muscle Training
3.1 Concepts of Neuromuscular Rehabilitation and Pelvic Floor Muscle Training Jo Laycock Key Messages Introduction • The principles of muscle training are overload, Muscle training involves the improvement in the specificity, and reversibility. tone of muscles or muscle groups, providing a readiness for action , and includes improvement • Pelvic floor muscles work synergistically with in stiffness, strength, endurance, coordination, the deep abdominal muscles, the lumbar mul- and function. Much of the evidence of the tifidi muscles, and the respiratory diaphragm, efficacy of muscle tra ining and the principles forming a cylinder to support the lumbar involved has come from sports medicine litera- spine. tu re.!\" In addition to increasing the cross- sectional area and neuromuscular function, • With contraction of the transverse abdominis strength training has been shown to increase the muscle, the pelvic floor muscle is coactivated, connective tissue within and around the muscles,22 and this pattern can be used in pelvic floor and , in theory, should improve the support of the re-education. pelvic organs afforded by the pelvic floor muscles. However, there are a number of differences • Reduced endurance of pelvic floor contraction between pelvic floor muscle rehabilitation and is mainly a slow-twitch fiber disorder and the training of muscles of sports women and requires endurance training by increasing men, which should be considered alongside the the length of contractions and the number of general principles described below. The main dif- repetitions. ferences are the difficulty of teaching and assess- ing correct pelvic floor muscle contractions in • Reduced pelvic floor strength is predominantly functional posit ions and the motivation for a fast-twitch fiber disorder and requires people to carry out a program of exercises. Teach- strength training with maximum voluntary ing and assessing a correct pelvic floor muscle contractions until the muscles fatigue. contraction is addressed in Chapter 2.1 and also in the section on biofeedback (see Chapter 3.2). • In patients with stress urinary incontinence, Motivation and adherence to training programs even moderate pelvic floor contractions before is discussed in the following sections. increases in intraabdominal pressure can reduce stress incontinence. Another fact has to be considered; athletes in training usually have normal and strong muscles, • In patients with OAB, during an episode of and training aims to hypertrophy these muscles urgency, several maximum contractions may and improve performance. However, patients help by inhibiting the overactive detrusor with pelvic floor muscle dysfunction may have muscle. • Adherence to a pelvic floor exercise program is influenced by the patient's understanding of the causes, the consequences of the condition, and the perceived sequelae of noncompliance. 177
178 J.Laycock damaged muscles, damaged muscles and fascial on-going process, which takes 15-20 weeks; attachments (see Chapter 1.1), partially dener- top athletes are continuously improving. Re- vated/re-innervated muscles (see Chapter 1.2), versibility implies that the training effect is and lack of pelvic floor awareness. The aim here reversed; hypertrophy is lost and performance is is to rehabilitate, re-educate, and so restore reduced if the training stops; this is a gradual normal or near-normal function, and to intro- process.' :' duce a compensational muscle action to counter- balance other insufficiencies, such as connective Principles in Pelvic Floor tissue weakness and irreparable changes. Yet Muscle Training another problem in pelvic floor rehabilitation is the often difficult diagnosis of the underlying Overload and Specificity causes, the damage, and the functional defects. Principles ofGeneral Muscle Training Pelvic floor muscle assessment of a patient with incontinence will establish whether the muscles A muscle-training program should satisfy the are weak (reduced strength - predominately a following principles: overload, specificity, and fast-twitch fiber disorder), or easily fatigued reversibility.'? (reduced endurance - mainly a slow-twitch fiber disorder), or dysfunctional. The latter case is Overload seen when a woman either cannot perform a vol- untary pelvic floor muscle contraction, or can This term implies the need to make the particu- perform a strong pelvic floor muscle contraction lar muscles work more than they have been used while lying supine, but cannot manage this while to; to work harder, to work longer, to push their standing or during coughing . Specificity implies performance to the limit. Overload can be applied that if the muscles are weak, then strength train- to strength, endurance, and function/technique. ing is required. This involves maximum volun- Exercise regimens progress by demanding more tary contractions until the muscles fatigue effort over a longer period of time to push the (overload). If on assessment the muscles are performance to a higher limit. found to tire easily (producing only short con- tractions and/or few repetitions), endurance Specificity training is needed . This will involve the patient aiming to increase the length of contraction (hold Specificity describes \"training for a purpose,\" time) and increase the number of repetitions. and examines the specific objective of the exer- This is done by repeating longer, submaximal cise. Overload and specificity can generally be contractions. considered together. For example, a sprinter may train specifically for speed, recruiting mainly Many patients present with a deficiency in both fast-twitch muscle fibers, whereas a marathon strength and endurance. Continuous reassess- runner requires endurance, which is when pre- ment during a course of treatment is necessary to dominately slow-twitch muscle fibers are ensure that overload is satisfied. This highlights recruited; thus, these runners would apply speci- a further difference between training athletes ficity to their training programs. By running and training women with incontinence; the faster than previously (sprinter) or longer than exercise science literature recommends 8-12 previously (marathon runner), they are also maximum contractions in three sessions, and applying overload. three or four training sessions per week, with rest days for recovery.'? Many patients with weak Reversibility: Loss ofHypertrophy pelvic floor muscles who are in a rehabilitation program cannot perform eight maximum con- With athletes, strength training aims to hyper- tractions of sufficient strength and endurance to trophy the appropriate muscles; this is an have a training effect; thus, they need to practice several times each day, at least 6 days a week.
3.1. Concepts ofNeuromuscular Rehabilitation and Pelvic Floor Muscle Training 179 Improving function is the most important continence, or reduced incontinence. However, training parameter, and this should be assessed because of the ageing process\" and other factors, and addressed accordingly. In a study by Miller e.g. constipation,\" when muscles weaken because et al., older women with stress urinary inconti- of reduction of motor units it is necessary to con- nence on coughing were taught \"The Knack .\" tinue with pelvic floor muscle exercises not only This is an anticipatory pelvic floor muscle con- to keep the training effect but also to compensate traction before and during a cough.' Th is study for these additional confounders so as to prevent is a fine example of specificity, and demonstrated incontinence from recurring. This is not true that it is not necessarily the strength of the con- reversibility, but implies that incontinence symp- traction, but the ability to use the pelvic floor toms may worsen if pelvic floor muscle exercises muscles specifically when needed, to prevent are discontinued or reduced. However, Bo sug- incontinence, that is important. Another good gests that telling patients that they should con- example of specificity is \"holding on,\" which is tinue with pelvic floor muscle exercises for life described by Norton, for patients with fecal urge may demotivate them.\" The key is, when strength incontinence.\" A randomized controlled trial\" training has been carried out successfully, to demonstrated that patients who only practiced integrate the pelvic floor muscles into daily \"holding on\" to defer defecation improved, as routine and functional tasks. They should start well as those practicing \"holding on\" sphincter to act automatically whenever there is an increase exercises and biofeedback. in intraabdominal pressure, thus, maintaining a training effect. Taking specificity a step further dictates the way pelvic floor muscle exercises are taught. Pelvic Floor Muscle Exercises: Coaetivation Patients are instructed to \"squeeze and lift the of Synergists muscles between the legs, as if preventing urina- tion/defecation\"; this is thought to enhance cor- During low levels of activity, the smooth muscle tical awareness of the specific function of fibers and fatigue-resistant slow-twitch fibers in the muscles . Simply instructing the patient to the periurethral part of the levator ani are pre- \"squeeze and lift\" may reduce this effect. dominately activated. When activity increases, fast-twitch fibers are also recruited.?'? The pelvic Rothstein et al. suggest that to integrate an floor muscles act along with the abdominal activity or skill into normal, automatic, or uncon- muscles (especially transversus abdominis [TrA]), scious function, many repetitions must be per- the lumbar multifidi muscles, and the respiratory formed under diverse functional situations.' This diaphragm, forming a cylinder of support for the supports the use of ambulatory surface EMGbio- spinal column (Fig. 3.1.1).11 feedback to ensure appropriate muscle recruit- ment in different positions. Furthermore, Grimby The muscles of this cylinder all respond to and Hannerz directly relate proprioceptive dys- changes in intraabdominal pressure; this includes function to dysfunction of tonic or slow motor changes in posture, coughing, walking, talking, unit recruitment,\" and so submaximal pelvic deep breathing, and using the upper limbs. The floor muscle contractions with extended hold timing of this response may be critical, and times should be practiced. studies have shown that a delay in recruitment or inhibition of the multifidis muscles may be caused As with athletes, all patients will start at dif- by pain \" or muscle weakness.\" Constantinou ferent levels, and so will require patient-specific and Govan demonstrated that recruitment of the exercise programs that are applicable to their periurethral muscles on coughing occurred needs. As fitness improves, the program should 250msec before an increase in intraabdominal become more challenging. pressure.\" This suggests that a delay in periure- thral muscle recruitment may be a cause of Reversibility: Loss of Function with incontinence. However, Verelst and Leivseth \" Deterioration ofCofaetors have shown no difference in this parameter between continent and incontinent patients. In pelvic floor rehabilitation, therapy continues until agreed goals are reached; e.g., this may be
180 J.Laycock D iaphragm -~-\"\"\"\"\"- support the training ofTrA alone, and Dumoulin et a1.22 showed no difference between pelvic floor Transversus muscle strength training alone and combined abdominis with TrA training. Clearly, more research is needed to clarify the optimum way the pelvic Pelvic floor --+~~\".II'i~ floor muscles are trained. FIGURE 3.1.1. Diagrammatic representation ofthe muscular cyl- A good posture requires that the muscles of the inder (capsule) ofsupport for the lumbar spine. Itincludes the cylinder of support for the spinal column (pelvic diaphragm, multifidi, transversus abdominis and pelvic floor floor, multifidi, and transverse abdominis) work muscles. synergistically together. An improvement in posture initially produces increased activity in Clearly, in health, all of these cylinder muscles the pelvic floor muscles, and so good posture orchestrate their recruitment as required, and so should be encouraged in sitting and standing. rehabilitation of the pelvic floor muscles should Exercising on an air cushion or balance ball while include attention to these other muscle groups. maintaining an upright posture is thought to There is evidence of functional activation of the recruit the pelvic floor muscles,\" but more pelvic floor muscles - in particular pubococ- research is needed in this area . cygeus - with the TrA muscle,\" and so it has been suggested that exercises for the TrA can be used Another coactivation concerns the glutei to indirectly activate the pelvic floor muscles, muscles, which contribute to movement of the and should be part of the rehabilitation program. coccyx (see Fig. Ll.8, A and B). A mobile coccyx The TrA muscle is activated by instructing the probably supports the ventro -cranial movement patient to \"gently draw in\" the lower abdominal of the puborectalis muscle and elevation of the wall, minimizing any movement of the upper bladder neck. abdominal wall and the rib cage. This contrac- tion should be around 25% of a maximum volun- Concept ofPelvic Floor Muscle tary TrA contraction. As the aim is to enable the Recruitment inStress Incontinence patient to use the pelvic floor muscles and TrA functionally, a normal breathing pattern should Involuntary loss of urine caused by an increase be used . Once both TrA and the pelvic floor in intraabdominal pressure, e.g., coughing, muscles have been identified, they should be assumes that bladder pressure has exceeded ure- exercised together, aiming for lO-s sustained thral pressure; consequently, therapies aimed at contractions repeated 10 times.\" However, there increasing urethral pressure should reverse this are no randomized controlled trials (RCTs) to situation and ameliorate the problem (Fig. 3.1.2). Urethral pressure is caused by a number of factors including smooth and striated muscles, and elastic and vascular tissues . In addition, muscu- lar and fascial support of the urethra and bladder maintains the organs in position (see Chapter l.l), Of the factors listed above, striated muscles are the target of physiotherapy, and these include the striated urethral sphincter muscles and the levator ani muscle. The urethral sphincter is responsible for increasing intraurethral pressure, and the pelvic floor muscles, particularly the pubococcygeus and puborectalis, are responsible for elevating the proximal urethra and maintain- ing this position during increased intraabdomi- nal pressure. Clearly,both of these muscle groups should be targeted in an exercise program. In
3.1. Concepts ofNeuromuscular Rehabilitation and Pelvic Floor Muscle Training 181 A( FIGURE 3.1.2. A. Pelvic floor at rest. B. Apelvic floor contraction asa pre-contraction (\"Knack\"). (Source: modified from Schussler results in cranio-ventral displacement ofthebladder neck (arrow B. Aims of pelvic floor evaluation. In: Schussler B, Laycock J, shows the vector). C. This contraction can actas an opposition Norton P, Stanton S, editors. Pelvic floor re-education: principles during coughing e.g. Physiologically this contraction is generated and practice. London:Springer-Verlag; 1994:39.) viaareflex and co-contraction. In incontinent patients itis trained continent women, co-contraction of the pelvic Adherence to an Exercise Protocol floor and sphincter muscles is demonstrated before and during coughing; consequently, this The evidence supporting factors that influence should be taught to women with SUI on motivation/adherence to an exercise program for coughing. This has been described as \"The incontinence is scant. The literature on adher- Knack\".' This technique can be applied to any ence relating to heart disease and asthma high- activity causing incontinence, e.g., lifting. In lights a number of interesting options described many cases, a moderate contraction is sufficient by Chiarelli,\" Those, as well as other principles to prevent urine loss. Using ambulatory EMG and strategies to enhance recall, are shown in biofeedback or perineal ultrasound (see CD Boxes 1_3.18 The aims of pelvic floor rehabilita- and Chapter 2.6), patients can monitor their tion are to teach an appropriate exercise program, performance. which, along with advice on types and quantities of fluid intake, along with medication, will Concept ofPelvic Floor Muscle address the patient's symptoms. Clearly, such a Recruitment in Urge Incontinence program requires patient cooperation and will not be suitable for everyone. The perineodetrusor-inhibiting reflex described Box #1 by Mahoney et al. clearly describes detrusor inhi- Adherence toanexercise regimen depends on: bition as a response to pelvic floor muscle tone.\" Consequently, one can assume that the greater a • The patient's understanding of the diagno- pelvic floor muscle contraction, the greater the sis and cause of symptoms inhibition. As most patients with an overactive bladder cannot maintain a strong contraction • The patient's comprehension and recall of during an episode of urgency, they may need the exercise program to perform several maximum contractions of shorter duration, with a minimal rest period • The patient's beliefs and understanding (e.g. 1s) between contractions. As the detrusor is of the long-term consequences of the made of smooth muscle, it is very slow to respond, condition and so a short pause in the pelvic floor muscle contraction should not diminish the inhibitory • Any barriers to treatment effect. This is a further example of the principle • The perceived benefits and sequelae of non- of specificity in a training program. compliance • Ways of increasing the opportunities to practice • Providing cues or reminders to practice
182 J.Laycock Box #2 6. Norton C, Kamm M. Randomised controlled trial Factors to encourage adherence of biofeedback for faecal incontinence. Neurourol and Urodyn. 2002;21:295-296. • Perception of self-efficacy • Improving communication with the patient 7. Rothstein J, Roy S, Wolf S. The rehabilitation spe- • Goal setting cialist's handbook. Philadelphia: FA Davis Co.; • Program with minimal lifestyle changes; 1991. least disruptive to daily routine 8. Grimby Land Hannerz J. 1976. Disturbance in • Simple (less complex) program • Check adherence voluntary recruitment order of low and high fre- quency motor units on blocades of proprioceptive Box #3 afferent activity. Acta Physiol Scand. 1976;96: Strategies to enhance recall 207-216 . 9. Petros PP, Skilling PM. Pelvic floor rehabilitation • Primacy - presenting the most important in the female according to the integral theory of information first female urinary incontinence. First report. Eur J Obstet Gynecol Reprod BioI. 2001;94:264-269. • Stressing and repeating important facts 10. Jones R, Comerford M, Sapsford R. Pelvic floor • Using specific advice stability and trunk muscle co-activation. In: • Check on comprehension by asking patient Laycock J, Haslam J, editors . Therapeutic manage- ment of incontinence and pelvic pain. London: to repeat instructions in their own words Springer -Verlag; 2002:66-71. • Use written instructions, and , wherever 11. Bo K. Pelvic floor muscle training is effective in treatment of female stress urinary incontinence, possible, have the patient write these but how does it work? Int Urogynecol J. 2004; • The use of reminders e.g. small colored stick- 15:76-84. 12. Hodges P, Richardson C. Altered trunk muscle ers around the house recruitment in people with low back pain with upper limb movement at different speeds . Arch References Phys Med Rehabil. 1999;80:1005-1012. 13. Hides JA, Richardson CA,[ull G. Multifidus muscle 1. Astrand PO, Rodahl K. Textbook of work physiol- recovery is not automatic after resolution of acute, ogy: physiological basis for exercise. McGraw Hill first-episode low back pain . Spine. 1996;21:2763- Company; 1988. 2769. 2. American College of Sports Medicine Position 14. Constantinou CE and Govan DE. Spatial distribu- Stand. The recommended quantity and quality of exercises for developing and maintaining card io- tion and timing of transmitted and reflexly gener- vascular and muscular fitness in healthy adults. ated urethral pressures in healthy women. J Urol. Med Sci Sports Exerc. 1990;22:265-274. 1982;127:964-969. 15. Verelst M, Leivseth G. Are fatigue and distur- 3. Bo K. Pelvic floor muscle exercise for the treat- bances in pre-programmed activity of pelvic floor ment of stress urinary incont inence: an exercise muscles associated with female stress inconti- physiology perspective. Int Urogyecol J. 1995;6: nence? Neurourol and Urodyn. 2004;23 :143-147. 282-291. 16. Sapsford R, Hodges PW. Contraction of the pelvic floor muscles during abdominal manoeuvres. 4. Miller J, Ashton-Miller J, DeLancey JOL. A pelvic Arch Phys Med Rehabil. 2001;82(8):1081-1088. muscle precontraction can reduce cough related 17. Mahoney DT,Laferte RO,Blais DJ.Integral storage urine loss in selected women with mild SUI. J Am and voiding reflexes. Neurophysiologic concept of Geriatr Soc. 1989;46:870-874. continence and micturition. Urology. 1977;9: 95-106. 5. Norton C, Chelvanayagam S. Conservative man- 18. Chiarelli PE. Improving patient's adherence. In: agement of faecal incontinence in adults. In: C LaycockJ, Haslam J, editors. Therapeutic manage- Norton and S Chelvanayagam, editors. Bowel con- ment of incontinence and pelvic pain. London: tinence nursing. Beaconsfield, UK: Beaconsfield Springer-Verlag; 2002:73-74. Publishers; 2004 :118-119. 19. Wagg A. The ageing lower urinary tract. In: Laycock J, Haslam J, editors. Therapeutic manage- ment of incontinence and pelvic pain . London: Springer -Verlag; 2002:39-44.
3.1. Concepts ofNeuromuscular Rehabilitation and Pelvic Floor Muscle Training 183 20. Snooks SJ,Barnes PRH, Swash M and Henry MM. trolled trial of pelvic floor rehabilitation with or Damage to the innervation of the pelvic floor mus- without abdominal muscle rehabilitation com- culature in chronic constipation. GastroenteroI. pared to the absence of treatment. Neurourol 1985;89:977-981. Urodyn . 2003;22:543-544. 22. Stone M. Implications for connective tissue and 21. Dumoulin C, Lemieux M, Bourbonnais D, et aI. bone alterations resulting from resistance exercise Conservative management of stress urinary in- training. Med Sci Sports Exerc. 2003;20 :162-168. continence: a single-blind, randomized, con-
3.2 Exercise, Feedback, and Biofeedback Pauline E. Chiarelli and Kate H. Moore Key Messages The second stage involves \"fine tuning\" of the new skill. Mistakes are made less and less fre- • Feedback is essential in motor learning. quently until, finally, the task becomes automatic • Intrinsic feedback: the subject self-assesses or and does not require much attention during its execution, which is the third stage of skill acquisi- senses the contraction. tion .' Although practice of the specific motor • Augmented feedback: involves the help of an learning task is of prime importance, feedback is considered the next most important variable.' assessor or device. • Biofeedback techniques include digital (tactile), When learning how to correctly perform a motor task, e.g. an effective PFM contraction, verbal, visual, electromyographic (visual or sensory information or feedback is received by auditory), and manometric (simple or com- the person either during or after each contraction puterized) methods; perineal and abdom- attempt. This feedback can be internal (intrinsic: inal ultrasound; andvaginal retention sensation, the subject self-assesses or senses the contrac- as provided by weighted vaginal cones or tion) or external (augmented: feedback with the catheters and visual feedback during help of an assessor or device).' In the case of cystourethroscopy. a PFM contraction, intrinsic feedback means • Proprioceptive, kinesthetic, and tactile per- \"feeling\" the muscle contraction, which involves ception of a pelvic floor muscle (PFM) con- proprioceptive, kinesthetic, or tactile cues.' traction are valuable to develop \"contraction During initial attempts at PFM contraction, many awareness.\" women cannot perform or perceive a contraction • Biofeedback can be used for autonomic func- and therefore receive little intrinsic feedback . For tions, such as detrusor overactivity and bladder this reason, digital assessment of PFM contrac- sphincter dyssynergia, during cystometry. tions with verbal feedback to the patient/subject is very important in the early stages ofPFM reha- Motor Learning and Biofeedback bilitation.' Subsequently, other forms of aug- mented feedback might be helpful. Motor learning is a complicated process resulting in the acquisition of new and, after practice, rela- Definition tively permanent motor skills . There are three stages to motor learning. The first stage is called Biofeedback in pelvic floor re-education consti- the cognitive stage and involves a person learning tutes an operant, cognitive, and respondent exactly what is required to perform a particular process by which the subject learns to reliably task and exactly how to perform that task cor- improve pelvic floor function. It entails repetitive rectly.' In this stage oflearning, feedback is essen- tial if the motor task is to be reproduced precisely. 184
3.2. Exercise, Feedback, and Biofeedback 185 responses and repeated teaching. It can involve feedback from the clinician during vaginal pal- pelvic floor functions that are not usually under pation can be used to describe a muscular voluntary control (such as detrusor muscle con- response that would otherwise be unnoticed by tractions), as well as responses that are usually the woman. This positive feedback should moti- under voluntary control, but are no longer easily vate the woman to contract the right muscles and regulated because of trauma or disease (e.g. PFMs continue with the exercise program. Extrinsic following traumatic vaginal delivery). Biofeed- feedback seems an appropriate strategy during back can be used to teach women to sustain, early intervention.' strengthen, direct, or eliminate a body action or reaction. The ultimate clinical goal of biofeed- To be able to contract, a muscle needs to have back is \"self\"-control without the need to use an intact nerve supply. In cases where nerve external biofeedback. supply is at least partially intact, but where women are unable to initiate a PFM contraction, Biofeedback in the Rehabilitation of verbal instructions describing how a woman the PFMs might correctly perform a PFM contraction have been shown to be quite unhelpful.\" Forty-seven In PFM rehabilitation, commonly used biofeed- women with stress or urge incontinence or pelvic back techniques include digital (tactile), verbal, organ prolapse were first given brief verbal visual, electromyographic (visual or auditory), instruction about how to perform PFM contrac- and manometric (simple or computerized) tion. The women were then asked to perform a methods; perineal and abdominal ultrasound; correct PFM contraction while a urethral pres- and vaginal retention sensation, e.g. as provided sure profile was undertaken to ascertain the by weighted vaginal cones. Biofeedback can also effectiveness of their contraction attempt. Only be given during a cystourethroscopy showing the 49% were deemed to have performed an effective conscious woman an open bladder neck, e.g. and PFM contraction.\" This study illustrates the fact how it can be closed. that simply telling women how to contract their PFM is not sufficient. To maximize their PFM Although augmented biofeedback initially contraction performance, contraction attempts cons isted of a simple pressure biofeedback device need to be enhanced by biofeedback. introduced by Arnold Kegel in 19484< (Chapter 3.5), biofeedback has been improved by comput- Tactile and Verbal Feedback erization and joined by a number of other bio- feedback methods, including electromyography The utilization of tactile sensation is an inexpen- (EMG), which records electrical activity within sive and readily available form of biofeedback in specific muscles, sensory biofeedback (cones), pelvic floor re-education. Proprioceptive, kines- PFM contraction indicator devices,\" and dynamic thetic, and tactile\" perception of a PFM con- ultrasound.Y traction are valuable to develop \"contraction awareness.\" Proprioception, to encourage the The PFMs are a \"hidden\" muscle group. Women \"squeeze\" component of a PFM contraction, can with PFM dysfunction are often unaware of the be provided by applying a gentle stretch to the presence of this muscle group and are unable to PFM by parting the inserted fingers laterally or in initiate any voluntary contraction. In trying to the ventral and dorsocaudal direction (Fig. 3.2.1). perform a PFM contraction, many woman use Because the levator animuscle is well endowed primarily other muscle groups such as gluteals with stretch receptors, in most cases, the woman and hip adductors\" or perform a Valsalva reports feeling the muscles being stretched and maneuver.\" can be encouraged to \"pull the examining fingers in an upward direction.\" Th is method can also be Enhancement ofPelvic Floor Awareness used to provide the resistance necessary within a muscle-strengthening program. The woman In the early stages ofPFM retraining, the woman's should be taught the different actions of an effec- muscle response might be minimal, and verbal tive PFM contraction, which not only includes a
186 P.E. Chiarelli and K.H. Moore Although digital assessment and feedback of a PFM contraction by the clinician will support the exercise program, digital self-assessment by the woman herself might be considered. However, digital self-assessment is limited because of the likely lack of knowledge of a normal pelvic floor. It has been shown that it is not carried out regu- larly following professional instruction11 because it can be physically difficult to perform. Visual Biofeedback FIGURE 3.2.1. Stretching ofthe levator ani muscle (modified from Simple visual biofeedback can be provided using Laycock J, Clinical Evaluation ofthe Pelvic Floor. In: Schussler B, a hand mirror to watch the PFMs as they con- Laycock J, Norton P, Stanton S, editors. Pelvic Floor Re-education: tract, elevate the perineum, and narrow the Principles andPractice. Springer-Verlag London Ltd, 1994:43). genital hiatus. This has been used successfully among postpartum women.\" \"squeeze\" action to pull the urethra forward against the pubic bone , but also a \"lifting\" Devices that provide visual biofeedback ofPFM action .\" during contraction include the \"Pelvic Floor Edu- cator\" (Neen Healthcare) (Fig. 3.2.3).5It employs Another inexpensive biofeedback method the use of a vaginal probe with a thin, but long, involves the use of a large-gauge urethral cathe- plastic rod attached to it. During a correct pelvic ter that is inserted vaginally and then inflated. floor contraction - and only then - the rod will tilt This provides beneficial visualization of the cath- downward, whereas during pushing or coughing eter elevation during pelvic floor contraction and the rod will move upwards.\" can also be used in standing (Fig. 3.2.2). Volun- tary retention of the inflated vaginal catheter Kinesthetic Biofeedback during coughing while standing offers excellent biofeedback and is also a powerful teaching Weighted vaginal cones were initially designed tool. and described by Plevnik in 1988:4 Varying weights are inserted intravaginally, above the level of the PFM, while the woman performs upright, sedate activities of daily living . Feed- back occurs when the cone begins to slip down- wards in the vagina (kinesthetic perception), causing the woman to contract her PFM in order to prevent the cone from escaping the vagina. FIGURE 3.2.2. An inflated indwelling cath- eter in the vagina provides biofeedback when itislifted during pelvic floor contrac- tion. Additional traction onthe catheter by the subject or clinician will enhance the retention feeling and the pelvic floor con- traction can betrained to prevent slipping ofthe catheter.
3.2. Exercise, Feedback, and Biofeedback 187 FIGURE 3.2.3. The plastic rod isattached toa vaginal probe. With a sufficient pelvic floor contraction the rod rotates dorsally asthevagina is displaced ventrally. (Fig. 3.2.4). Anecdotally, older women tend to be provide EMG feedback during PFM rehabilita- less accepting of the use of weighted vaginal tion. (Fig. 3.2.5). Feedback can be given in cones within PFM exercise programs. numbers, bars, or curves on a screen showing how strong a contraction is performed over Electromyographic Biofeedback time. The electrical activity of motor units is generated Manometric Visual Biofeedback by depolarization, registered as motor unit action potentials, and can be recorded in EMG studies Kegel designed the first manometric device to (Chapter 1.2). Electromyographic signals are give women an incentive to increase the contrac- picked up using fine wire electrodes implanted tile power of their PFM by providing biofeed- within a muscle; alternatively, surface electrodes back (Fig. 3.5.1). The perineometer records can be used , but they are considered less specific changes in vaginal pressure during PFM contrac- than fine wire electrodes. However, fine wire tion. Depending on the design and posit ion of the EMGis not widely used in PFMretraining because probe, it will also detect increased abdominal of the invasive nature of the procedure. The EMG pressure during straining or coughing. biofeedback can be given as visual or auditory feedback . Endovaginal and endoanal \"surface\" Vaginal and anal pressure biofeedback units electrodes have been developed and used to can directly record the changes in pressure caused by the contraction of the circumvaginal FIGURE 3.2.4. Set ofvaginal cones, weighing 20-70 g.The vaginal weight isinserted into thevagina above thelevel ofthelevator ani. The sensation thatthecone might slip generates a pelvic floor contraction.
188 P.E. Chiarelli and K.H. Moore AB FIGURE 3.2.5. (A and B) Vaginal EMG-electrode and hand-held device used to provide biofeedback. Strength, endurance and timing ofpelvic floor contractions can bepracticed in everyday situations. musculature (e.g. in mm Hg) and display them needs of physiotherapists, a small, mobile unit on a handheld gauge. More sophisticated means required only for biofeedback in muscle training of amplifying the muscle response have emerged, is now available. including using computers to display the muscle response onscreen. This technique also allows Biofeedback to Control the examiner to assess the pressure-time rela- Detrusor Overactivity tionship of contractions, endurance, and coordi- nation to monitor training progress, and to Biofeedback can be used in patients with unstable compare results intra- and interindividually. detrusor contractions and bladder sphincter dys- synergia. During cystometric investigations, the Sonography: Dynamic Ultrasound intravesical pressure is recorded and presented to the patient as an auditory and visual signal. Real-time perineal and abdominal ultrasound Patients watch the urodynamic trace throughout offers the opportunity to specifically observe the the test while they try to inhibit detrusor contrac- elevation of the bladder neck during a PFM con- tions with PFM contractions. The treatment has traction and bladder neck descent during a Val- had some measure of success, but patients have salva maneuver or coughing (see Chapter 2.5). to be highly motivated, and the intervention is Perineal ultrasound has been shown to selectively time consuming in terms of operator time.\" depict PFMactivity better than intravaginal EMG and perineometry,\" Tactile and Visual Biofeedback During Cystourethroscopy Transperineal ultrasound has been used as a reliable method of demonstrating to women the During cystourethroscopy, the bladder neck contraction of their PFM and the elevation of movement during coughing and pelvic floor con- their bladder neck. This was used successfully in traction is visible. The patient can be encouraged women initially unable to voluntarily contract to close the bladder neck with a pelvic floor con- their PFM.7 More recently, transabdominal ultra- traction and keep it closed during coughing (see sound has been shown to be an alternative, video on DVD). This method of biofeedback can although the visualization of the bladder neck is only be applied if there is an indication to perform limited (see Chapter 2.5).18 In response to the an office cystoscopy.
3.2•. Exercise, Feedback, and Biofeedback 189 Summary 8. Bo K, Larsen S, Oseid S, et al. Knowledge about and the abilityto perform correct pelvic floor muscle To date , there is little evidence that the use of exercises in women with urinary stress incont i- biofeedback improves the outcomes of regular nence. Neurourol Urodyn. 1988;7(7):261-262. pelvic floor treatment programs. Although various forms of biofeedback are readily avail- 9. Bump RC, Hurst G, Fantl JA, et al. Assessment of able for use and can be very helpful in the indi- Kegel pelvic muscle exercise performance after vidual patient, the value of biofeedback has also brief verbal instruction. Am J Obstet Gynecol. to be measured in terms of improved outcomes 1991 ;165(2) :322-329. versus cost. 10. Schussler B. Radiological evaluation of the pelvic However, the most important judgment has to floor and viscera. In: Schussler B, Laycock J, come from the subjects, and future studies should Norton P, Stanton S, editors. Pelvic floor re- address the woman's perspective on the useful- education: Principles and practice. London : ness of biofeedback. Understanding pelvic floor Springer-Verlag; 1994:75-82. function, teaching correct muscle coordination, and assessing progress are features beneficially 11. Chiarelli P. Female urinary incontinence in Aus- provided by biofeedback . tralia: prevalence and prevention in postpartum women [doctoral thesis]. Newcastle (Australia): References University of Newcastle; 2001. 1. Gentile A. Skill aquisition: action, movement and 12. Chiarelli P, Cockburn J. Promoting urinary conti- neuromotor processes. In: Carr J, Shepherd R, Gordon J, editors. Movement science: Foundations nence in women following delivery: randomised for physical therapy in rehabilitation. Rockville , controlled trial. Br Med J. 2002;324(25):1241- MD: Aspen Systems; 1987. 1247. 13. Chiarelli P, Brown W. Perineal elevation - the reli- 2. Kisner C, Colby 1. Therapeutic exercise: Founda- ability testing of a new measure of pelvic floor tional concepts. In: Kisner C, Colby L, editors. muscle function . In: Continence Foundation of Therapeutic exercise: Foundations and tech- Australia 8th National Conference on Inconti- niques. Philadelphia: FA Davis Co; 2002:3-33. nence . Sydney: Cont inence Foundation of Austra- lia; 1999. 3. Nicholson D. Teaching psychomotor skills. In: 14. Plevnik S. New method for testing and strengthen- Shepard KF, Jensen GM, editors. Handbook ing of pelvic floor muscles. In: 15th annual meeting of teaching for physical therapists. Boston: of the International Continence Society. London: Butterworth-Heinemann; 1997:271. ICS; 1988:95-1049. 15. Basmajian. Muscles alive. Their functions revealed 4. McNevin N, Gabriele W, Carlson C. Effects of by electromyography. 3rd edition. Baltimore: attentional focus, self control and dyad training Williams and Wilkins; 1974. on motor learning: Implications for physical reha- 16. LeCraw D, Wolf S. Electromyographic biofeedback bilitation. Phys Ther. 2000;80(4):373-385. (EMGBF) for neuromuscular relaxation and reed- ucation. In: Gersh M, editor. Electrotherapy in 4a. Kegel AH. Progressive resistance exercise in the rehabilitation. Philadelphia: FA Davis Company; functional restoration of the per ineal muscles. Am 1993:291-327. J Obstet Gynecol 1948;56:238-248. 17. Peschers U, Gingelmaier A, Jundt K, et al. Evalua- tion of pelvic floor muscle strength using four dif- 5. Haslam J. Biofeedback for the assessment and re- ferent techniques. Int Urogynecol J. Pelvic Floor Dysfunct. 2001;12:27-30. education of the pelvic floor musculature. In: Laycock J, Haslam J, editors. Therapeutic manage- 18. Thompson J, Briffa K, Court S. The comparison ment of incontinence and pelvic pain. London: Springer-Verlag; 2002:75-81. between tr ansperineal and transabdominal ultra- 6. Dietz H, Clarke B. The urethral pressure profile sound in the assessment of women performing and ultrasound imaging of the lower ur inary tract. pelvic floor exercises. In: Continence Foundation Int Urogynecol J. 2001(B);12(l):38-41. of Australia (CFA) 12th National Confere nce. 7. Dietz H, Wilson P, Clarke B. The use of perineal Sydney: CFA; 2003:39. ultrasound to quantify levator activity and teach 19. Cardozo 1. Detrusor instability. In: Stanton S, pelvic floor muscle exercise. Int Urogynecol J editor. Clinical gynaecologic urology. St. Louis: C Pelvic Floor Dysfunct. 2001;1 2:166-169. V Mosby; 1984:193-203.
3.3 Electrical Stimulation Wendy F. Bower Key Messages function.' Table 3.3.1 outlines the applications of electrical stimulation for pelvic dysfunction. • Large-diameter nerve fibers supplying the pelvic floor and urethral striated muscles are Mechanisms ofAction of stimulated directly by electrical stimulation. Pelvic Electrotherapy • 35-50 Hz creates a strong pelvic floor Activation of the PFMs by electrical stimulation contraction. has been shown in animal experiments to be primarily caused by the direct activation of • 5-10 Hz, with a pulse width of 0.5-1.0 ms, facili- pudendal nerve efferents. Single-fiber electro- tates inhibition of an overactive detrusor via myographic (EMG) studies in humans have inhibitory motor-neurons of the pudendal shown that pelvic floor stimulation elicits pelvic nerve. striated muscle responses . Electrical stimulation depolarizes the peripheral somatic motor fibers • Typical sessions last approximately 20-40 min of the pudendal nerve within the PFM, which daily to once per week for 12 weeks. contract the urethral striated sphincter and draw in the pelvic floor skeletal musculature. This arti- • Anatomical vaginal and anal probes allow close ficial recruitment of PFM induces a training stimulation of the pelvic floor. effect, allowing the patient to develop sensory awareness of muscle activity. It also provides an • Surface electrodes can be placed on the opportunity for motor planning and practice of perineum and anus if indicated, but the appli- pelvic floor contractions while the muscle is weak cation time should be longer because of the and response is imperceptible. Axonal budding high impedance of the skin. after denervation, and an increase in vascular- ization and hypertrophy have all been reported • Electrical stimulation at 35-50 Hz enhances after stimulation of pelvic skeletal muscles.' awareness of the pelvic floor, is better than no Although regular recruitment of any muscle treatment, and is particularly useful in women results in hypertrophy and enhanced fiber effi- who are unable to contract the pelvic floor ciency, voluntary contraction gives superior muscles (PFMs). muscle remodeling compared to passive electri- cal recruitment.r\" Introduction Depolarization of sensory fibers of the puden- Electrotherapy is the application of electrical dal nerve also generates a reflex response (elec- current to provoke nerve activity and to stimu- tric neuromodulation) with inhibition of an late function in different organ systems. The aim of electrical stimulation within the pelvic floor region is to induce skeletal muscle training, remodel smooth muscle and or connective tissues and to modulate bladder, bowel, or sexual dys- 190
3.3. Electrical Stimulation 191 TABLE 3.3.1. Application of electrical therapy for pelvic dysfunction (ICS Standardization Terminology of LUT Rehabilitation) AIMS Mode of action Facilitatevoiding - Stimulateafferent fibers toconvey bladder filling sensation Restore continence - Stimulate efferent fibers/ detrusor muscle to Control pelvicpain induce bladder contraction Improvesexual function Improve anal - Improve urethral closure continence/defecation/constipation - Re-educate andcondition PFM - Abolish/reduce detrusor overactivity - Relax PFM overactivity - Increase local blood flow - Enhance vascular and skeletal muscle competence - Increase gutmotility - Enhance puborectalis function and external anal sphincter closure - Induce appropriate relaxation of overactive PFM overactive sphincter. Besides these so-called moderate in diameter, and group C fibers are peripheral effects, there are also central effects, unmyelinated and primarily involved in somatic which consist essentially of reorganization, reco- pain responses.\" ordination, and awareness of the lower urinary tract, especially with respect to pelvic floor The intensity of the stimulation requ ired function. depends on the size of the afferent nerve fiber and its distance from the electrode. Because of pain The overactive bladder is frequently thought to perception, all clinical applications of electrical be caused by deficient central inhibition. Electri- stimulation are well below the threshold for cal stimulation at optimal parameters serves to maximal reflex inhibition. The large-diameter rebalance the descending excitatory information nerve fibers serving striated urethral and para- by artificially act ivating bladder-inhibiting urethral muscles can be stimulated directly, uti- reflexes. Peripheral effects, such as altered neuro- lizing a frequency close to the natural firing rate transmitter concentration, are also seen. It is of the motorneurons. Although 50Hz creates a known, for example, that beta-adrenergic activ- strong, forceful contraction with minimal fast- ity in the detrusor increases after repeat electri- twitch muscle relaxation between pulses, it can cal stimulation, whereas cholinergic activity is produce muscle fatigue. '? Thus, a frequency of decreased. ' 35-40 Hz is commonly used, and attention is paid to lengthening the rest period between cycles of Methods of Peripheral wavefronts (known as the \"duty cycle\"). Electrical Stimulation The inhibitory motor neurons facilitate The effect of electrical stimulation depends max imal inhibition of the overact ive detrusor on the distance between the nerve and the elec- at 5-10 Hz.II If stimulation is applied close to trode, the excitability of the nerve fibers, the non-muscular pud endal nerve afferents, weaker quality of central pulse transmission, and the impulses will affect bladder inhibition. Pulse properties of the effector organ.\" Conduction width is optimally 0.5-1.0ms, with stimulation speed of nerve fibers increases with fiber diame- being either continuous or involving a very short ter and degree of myelination. Group A fibers are duty cycle. the largest and are involved in motor function and sensory perception, group B fibers serve the Historically, there are two main methods of viscera in a sensory and motor capacit y and are electrical stimulation; chronic low intensity stim- ulation over a long period or maximum vaginal! anal stimulation over a short per iod. Chronic stimulation is based on daily stimulation over
192 W.F.Bower A B FIGURE 3.3.1. A. Different available vaginal and anal probes. B.Different hand-held displays. 1-12 hours via vaginal or anal plugs for a dura- electrodes, or an electromagnetic field induced in tion of up to 12months.\" The impulses are bipha- the pelvic region. Surface electrodes, such as sic and weak, with a maximum of 12V. The duty those used in TENS,offer the possibility oflonger- cycle is set so that the rest phase is at least double term current application, and perhaps enhance the working time. This method of stimulation the effect on neural plasticity. Stimulation can favors PFM weakness. The time commitment be provided by a Mains-powered or portable required by the patient reduces the acceptance of battery-operated machine, making daily home this method. treatment realistic. Most clinicians prefer to use maximum electri- Electrical Stimulation in Practice cal stimulation for overactive bladder symptoms or mixed urinary incontinence. Individual treat- Electrotherapy aims at developing PFM aware- ment sessions last around 20 minutes and are ness, increasing PFM bulk, strengthening the applied anywhere from daily to once per week for perineal closure reflex, or inhibiting detrusor a period of at least 12 weeks. Monophasic cur- overactivity. As part of an overall treatment rents are delivered by vaginal and/or anal plugs approach, adjunctive electrical stimulation has a at an intensity close to the patient's limit of toler- role for patients of both genders who present with ance. Because the vagina offers a route of low PFM weakness (with or without urinary inconti- impedance (low resistance of the vaginal mucosa), nence), fecal incontinence, urge or mixed type current delivery via probe electrodes has been incontinence, PFM overactivity, or pelvic/peri- favored. The currently available probes are ana- neal pain syndromes. tomically shaped to allow good contact to the pelvic floor muscle and/or anal sphincter (Fig. It is important to place the role of electrical stimulation in context; can the patient expect a 3.3.1). cure or appreciable improvement, is it merely However, stimulating the branches of the \"worth a try\" until scheduled surgery, or is it adjunctive to other intervention methods? Simi- pudendal nerve that are mainly or exclusively larly, the motivation and beliefs of a patient affect sensory nerves using surface electrodes (dorsal compliance in attending appointments or using penile/clitoridal nerve) is also common practice. the treatment at home. Previous negative sexual Electrodes can be placed at the anus or perineum experiences may also limit the use of genital elec- and just inferior to the pubic symphysis or coccyx. trical stimulation. Rarely is electrotherapy a Treatment of the overactive bladder variously stand-alone treatment, but more often occurs utilizes anogenital electrodes, transcutaneous with associated pelvic floor exercise regimes or delivery (transcutaneous electrical nerve stimu- lation [TENS]), sacral nerve electrode stimula- tion , percutaneous posterior tibial nerve needle
Search
Read the Text Version
- 1
- 2
- 3
- 4
- 5
- 6
- 7
- 8
- 9
- 10
- 11
- 12
- 13
- 14
- 15
- 16
- 17
- 18
- 19
- 20
- 21
- 22
- 23
- 24
- 25
- 26
- 27
- 28
- 29
- 30
- 31
- 32
- 33
- 34
- 35
- 36
- 37
- 38
- 39
- 40
- 41
- 42
- 43
- 44
- 45
- 46
- 47
- 48
- 49
- 50
- 51
- 52
- 53
- 54
- 55
- 56
- 57
- 58
- 59
- 60
- 61
- 62
- 63
- 64
- 65
- 66
- 67
- 68
- 69
- 70
- 71
- 72
- 73
- 74
- 75
- 76
- 77
- 78
- 79
- 80
- 81
- 82
- 83
- 84
- 85
- 86
- 87
- 88
- 89
- 90
- 91
- 92
- 93
- 94
- 95
- 96
- 97
- 98
- 99
- 100
- 101
- 102
- 103
- 104
- 105
- 106
- 107
- 108
- 109
- 110
- 111
- 112
- 113
- 114
- 115
- 116
- 117
- 118
- 119
- 120
- 121
- 122
- 123
- 124
- 125
- 126
- 127
- 128
- 129
- 130
- 131
- 132
- 133
- 134
- 135
- 136
- 137
- 138
- 139
- 140
- 141
- 142
- 143
- 144
- 145
- 146
- 147
- 148
- 149
- 150
- 151
- 152
- 153
- 154
- 155
- 156
- 157
- 158
- 159
- 160
- 161
- 162
- 163
- 164
- 165
- 166
- 167
- 168
- 169
- 170
- 171
- 172
- 173
- 174
- 175
- 176
- 177
- 178
- 179
- 180
- 181
- 182
- 183
- 184
- 185
- 186
- 187
- 188
- 189
- 190
- 191
- 192
- 193
- 194
- 195
- 196
- 197
- 198
- 199
- 200
- 201
- 202
- 203
- 204
- 205
- 206
- 207
- 208
- 209
- 210
- 211
- 212
- 213
- 214
- 215
- 216
- 217
- 218
- 219
- 220
- 221
- 222
- 223
- 224
- 225
- 226
- 227
- 228
- 229
- 230
- 231
- 232
- 233
- 234
- 235
- 236
- 237
- 238
- 239
- 240
- 241
- 242
- 243
- 244
- 245
- 246
- 247
- 248
- 249
- 250
- 251
- 252
- 253
- 254
- 255
- 256
- 257
- 258
- 259
- 260
- 261
- 262
- 263
- 264
- 265
- 266
- 267
- 268
- 269
- 270
- 271
- 272
- 273
- 274
- 275
- 276
- 277
- 278
- 279
- 280
- 281
- 282
- 283
- 284
- 285
- 286
- 287
- 288
- 289
- 290
- 291
- 292
- 293
- 294
- 295
- 296
- 297
- 298
- 299
- 300
- 301
- 302
- 303
- 304
- 305
- 306
- 307
