Foot Problems in Older People Assessment and Management

46 ASSESSMENT Figure 3.10 Manual muscle testing techniques for the foot and ankle. AB A. Ankle dorsiflexion. B. Ankle plantarflexion. C. Inversion. D. Eversion. E. Lesser toe flexion. F. Lesser toe extension. G. Hallux flexion. H. Hallux extension. CD EF GH described in Table 3.11, the maximum force gener- ability of hand-held dynamometry for foot muscles ated by the body part is recorded in kilograms or was recently evaluated by Burns et al,76 who indicated Newtons. While intratester reliability of dynamometry that the reliability of foot inversion/eversion and is very high, intertester reliability is only moderate, as plantarflexion/dorsiflexion measurements was excel- the scores are affected by variations in technique and lent, with standard errors of measurement ranging the strength of the clinician.75 The test–retest reli- between 0.3 and 0.7 kg.

Diagnostic imaging 47 Table 3.13 Manual muscle testing grades PLAIN FILM RADIOGRAPHY Grade Meaning Plain film radiography (X-ray) is the most common used imaging modality for assessing musculoskeletal 4 – Normal Resists strong pressure foot problems in older people. Radiography is rela- 3 – Good Resists moderate pressure tively inexpensive, has a quick turnaround time and 2 – Fair Resists gravity through full range of can generate very high-quality images with only minimal radiation exposure.77 The standard foot series 1 – Poor motion generally includes a dorsoplantar projection and Resists gravity through partial range of lateral projection, taken either non-weightbearing or 0 – None weightbearing. Weightbearing radiographs are prefer- motion able to non-weightbearing radiographs, as the foot is No muscle activity captured in a more functional position, which enables representative postural measurements (such as arch A height) to be obtained. The dorsoplantar projection provides a clear image of the midfoot and forefoot; B however, the talus and calcaneus may be obscured by the distal end of the tibia and fibula. The lateral pro- Figure 3.11 The paper grip test. A. Hallux. B. Lesser jection clearly depicts the talus, calcaneus and medial toes. column of the foot; however, the superimposition of midfoot and metatarsal bones may make it difficult to DIAGNOSTIC IMAGING clearly view the lateral structures. A range of other projections may be ordered to specifically target Generally speaking, most common foot problems localised pathologies such as sesamoid disorders and affecting older people can be adequately diagnosed subungual exostoses. from information obtained from the medical history, initial assessment interview and physical examination. Features that can be readily observed from stan- However, several diagnostic imaging techniques can dard foot radiographs include overall bone density (as greatly assist in the diagnosis of a wide range of evidenced by generalised radiolucency), calcaneal and osseous and soft tissue pathologies that may develop Achilles tendon spurs, accessory bones, metatarsal in older people. Access to these modalities varies con- length variations, angular deformities (such as hallux siderably between professions and between countries, valgus), arch height and osteoarthritic changes (such so many foot-care specialists will find it necessary to as joint space narrowing, osteophytes, sclerosis and establish referral systems with medical specialists who subchondral cysts). Although very little soft tissue is have a greater scope of practice in this area. The role evident on plain film radiographs, it is not uncommon of diagnostic imaging for specific pathologies is dis- to observe thread-like calcifications of the dorsalis cussed in subsequent chapters; however, the follow- pedis artery in X-rays obtained from older people, ing section briefly outlines the structures that can be particularly those with diabetes.78 visualised with each modality. When assessing foot radiographs of older people, it is necessary to keep in mind that some apparently abnormal features are so common in this age group that they can be considered normal age-related changes. Such features include plantar calcaneal spurs, osseous irregularities in the ungual tuberosity of the distal phalanges (which may mimic psoriatic arthritis), enlargements of the base of the proximal phalanx due to spurring of the lateral interosseous ligaments, and localised loss of bone density in the proximal phalanx of the hallux, medial aspects of the first and fifth metatarsal heads and the navicular.78 When examining dorsoplantar radiographs, it also needs to be kept in mind that clawing of the digits may give a misleading

48 ASSESSMENT impression of joint space narrowing due to superim- include tendon pathology, synovial effusions, liga- position of the phalanges. ment rupture, plantar fascial thickening, ganglia, bur- sitis, Morton’s neuroma and various soft tissue BONE SCANNING neoplasms.88 Ultrasound may also be used to assist in the accurate guidance of corticosteroid injections for Bone scanning involves the intravenous injection of a conditions such as plantar fasciitis and retrocalcaneal radioactive isotope (most commonly, technetium- bursitis.89 99), which becomes distributed in the bloodstream and is ultimately taken up by the tissues. In the pres- COMPUTED TOMOGRAPHY ence of bone pathology, the increased blood flow and corresponding increase in osteoblastic activity in the The basic principle of computed tomography (CT) is affected region causes an accumulation of the isotope. to irradiate a slice of tissue from multiple angles and By converting this radioactivity into a visual image, measure the output from the opposite side, which areas of increased uptake can be easily identified.79 varies depending on the density of the target tissue.90 Bone scans are particularly useful for the identifica- This output is then mapped according to predeter- tion of stress fractures, bone tumours and Paget’s mined tissue-specific attenuation cut-off values and a disease.80 greyscale image is generated, with each shade of grey representing a different tissue type. The first CT scan- The main indication for bone scanning of the foot ners were only capable of generating an image derived in older people is insufficiency fracture, which most from a single slice; however, recent advances in com- commonly affects the metatarsals81–83 but may also puter technology have enabled multiple slices to be develop in the talus84 and calcaneus85 and may not be acquired, which can then be rendered into three- visible on plain film X-ray. Bone scanning has a much dimensional images. Unfortunately, the more slices higher sensitivity for detecting osseous changes, as obtained, the greater the dose of radiation the patient it reflects bone metabolism rather than structure. is exposed to, so the clinician needs to carefully con- However, bone scanning has a very low specificity, sider whether high-resolution images are necessary to which increases the likelihood of false-positive find- reach a diagnosis. CT has a relatively limited role in ings. In particular, there appears to be a high rate of the diagnosis of foot conditions, although it may be false-positive results for foot scans. A study of 60 useful in the examination of bony tumours, complex patients with foot pain and 30 asymptomatic controls fractures and chronic osteomyelitis.91 by O’Duffy et al86 reported that 24 of the controls demonstrated focal areas of increased uptake, most MAGNETIC RESONANCE IMAGING commonly in the metatarsophalangeal joints, the midfoot and the plantar aspect of the calcaneus. Magnetic resonance imaging (MRI) involves the application of radiofrequency pulses to the body that ULTRASONOGRAPHY match the resonant frequency of the body’s hydrogen atoms. The hydrogen atoms then re-emit this energy Diagnostic ultrasound involves the generation of as a magnetic resonance signal, which is detected as a very-high-frequency sound waves that are transmitted voltage by a receiver coil.92 The subsequent ‘relax- through a coupling gel to the body part being exam- ation times’ of the hydrogen atoms vary across differ- ined. Depending on the density of the target tissue, ent tissue types, which enables the construction of these sound waves are reflected in varying velocity and high-spatial-resolution images of soft tissue, cartilage wavelength and the aggregation of this information is and bone. MRI is a useful imaging modality for then used to construct a two-dimensional image of several foot pathologies, including osteochondral the underlying tissue.87 Ultrasound can capture high- lesions, stress fractures, tendon rupture, plantar fasci- resolution images of muscle, tendons, ligaments and itis, plantar plate rupture, Morton’s neuroma and soft tissue masses in real time, at relatively low cost. osteomyelitis.93,94 Unfortunately, the high cost of However, perhaps more than any other imaging tech- MRI scans precludes their wider application in the nique, ultrasound is highly operator-dependent and diagnosis of foot problems. requires considerable practice to become proficient.87 Foot conditions that may be detected with ultrasound

Functional assessment 49 FUNCTIONAL ASSESSMENT people.99 Similarly, measuring the time taken to rise from a chair five times (the sit-to-stand test) provides The ability to perform routine activities such as dress- an overall measure of physical ability and can identify ing, performing housework and shopping are key older people at risk of falling. Both walking speed and components of an older person’s independence and sit-to-stand have been shown to be impaired in older quality of life. As stated in the introduction, there is people with foot problems.66,100 Some objective tests now considerable evidence that foot problems have a of mobility are also accurate predictors of falls (see significant detrimental impact on these abilities. Clini- section on falls risk assessment). cal assessment of an older person’s functional ability and mobility is therefore an integral component of EVALUATION OF GAIT DISORDERS geriatric assessment, not only to determine the base- line status of the older patient but also as a way of At least 20% of older people report difficulty walking measuring the effectiveness of interventions. or require assistance with gait-related tasks.101 Although a small reduction in walking speed and ACTIVITIES OF DAILY LIVING step length appears to be a normal consequence of ageing,102 there is increasing evidence that most other Activities of daily living can be broadly categorised as: gait changes frequently observed in older people are (1) basic activities of daily living (BADLs), (2) instru- the result of underlying conditions that increase in mental activities of daily living (IADLs) and (3) prevalence with advancing age, such as osteoarthritis, advanced activities of daily living (AADLs). BADLs stroke, peripheral neuropathy and dementia. In many are considered necessary but not sufficient for main- older people with a gait problem, more than one taining independence, IADLs are necessary to main- potential contributing condition is present, which can tain an independent household environment and make accurate diagnosis difficult. AADLs are complex tasks requiring high levels of physical and cognitive functioning.95 Assessment of Classifying gait disorders functional status is relatively straightforward and may simply require a brief checklist to be completed by the Alexander & Goldberg103 have proposed a classifica- patient as part of the consultation. Several validated tion of gait disorders according to the level of the tools have also been developed, including the Barthel sensorimotor system they primarily affect. Low-level index, which consists of 10 questions relating to gait disorders are those that influence structures distal bowel continence, bladder continence, grooming, to the central nervous system, including peripheral toilet use, feeding, transfers, mobility, dressing, stair sensory impairments (such as peripheral neuropathy, climbing and bathing.96 These scales are able to vestibular disorders and visual problems) and periph- predict functional decline, institutionalisation and eral motor impairments (such as arthritic and myo- mortality in older people;97 however, they are gener- pathic conditions). Middle level gait disorders include ally not sensitive enough to detect short-term changes those resulting from spasticity (such as myelopathy, in relatively highly functioning older people. vitamin B12 deficiency and stroke), parkinsonism (idiopathic or drug-induced) and cerebellar ataxia OBJECTIVE MEASURES OF MOBILITY (resulting from alcohol abuse). High level gait disor- ders include cautious gait (resulting from behavioural Objective measures of gait and mobility, such as adaptations due to fear of falling) and those related walking speed and rising from a chair, are also useful to frontal lobe problems (such as stroke affecting the tools for assessing functional status and are sensitive cortex or basal ganglia). A summary of these disor- enough to be used as clinical outcome measures. ders, including their characteristic gait changes and Walking speed, which can be simply measured with a associated physical findings, is shown in Table 3.14. stopwatch over a set distance, provides an indicator of Although this system provides a useful clinical not only lower limb muscle strength but also balance, summary of gait changes associated with specific con- reaction time and psychological status.98 Prospective ditions, there is often considerable overlap in their studies have also shown that walking speed is a strong presentation. predictor of institutionalisation and mortality in older

50 ASSESSMENT Table 3.14 Classification of common gait disorders in older people Level Classification Condition Gait characteristics Associated physical findings Low Peripheral sensory Sensory ataxia Steppage gait Loss of tactile sensitivity and proprioception Peripheral motor Vestibular ataxia Weaving from side to side May fall to one side Nystagmus Visual ataxia Tentative, cautious Arthritic Shortened stance phase on Visual impairment Avoidance of weightbearing affected side Trendelenburg sign on affected side Limited knee flexion Middle Spasticity Myopathic and Exaggerated lumbar lordosis Decreased lumbar lordosis neuropathic Trendelenburg sign Stooped posture – proximal Waddling gait Kyphosis Foot slapping Weakness of hip musculature Myopathic and Foot drop neuropathic Steppage gait Weakness of ankle – distal dorsiflexors Leg circumduction Hemiplegia/paresis Loss of arm swing Leg weakness/spasticity Foot dragging Knee hyperextension Ankle equinovarus Paraplegia/paresis Bilateral leg circumduction Arm weakness/spasticity Scissor gait Leg weakness/spasticity Parkinsonism Small shuffling steps Cerebellar ataxia Absent arm swing Rigidity Freezing Bradykinesia Wide base of gait Trunk flexion Increased trunk sway Poor control of trunk Staggering Incoordination High Cautious gait Wide base of gait Fear of falling Shortened stride Frontal-related gait Cerebrovascular Decreased velocity Atherosclerotic disease disorders Wide base of gait Cognitive impairment Shortened stride Leg weakness/spasticity Decreased velocity Incontinence Difficulty initiating gait Freezing Clinical gait analysis tion of gait features shown in Table 3.14, including documentation of temporospatial parameters such as The clinical assessment of gait disorders involves a velocity, cadence and step length, is probably a suffi- thorough systems examination in addition to the cient basis upon which to determine whether a refer- direct observation of movement patterns. Gait analy- ral is required for further diagnostic evaluation. In the sis techniques range from simple visual observation clinical setting, all this requires is sufficient space to through to high-tech instrumented gait analysis pro- conduct a brief gait assessment (preferably at least cedures. For the foot-care specialist, visual observa-

Functional assessment 51 10 m) and a stop-watch. As a general rule, gait can systems currently limits their use to the research envi- be defined as impaired if the walking speed is less than ronment, scaled-down versions with lower sampling 0.6 m/s.104 frequencies and sensor resolution are likely to become more widely adopted in clinical practice in years to When considering the contribution of gait patterns come. The major benefit of these systems over simple to foot disorders, more detailed lower limb assess- footprinting techniques is that their outputs are truly ments may be required. The use of treadmills to quantitative, and various force, pressure and timing observe frontal plane movements of the foot during parameters obtained from the pressure recording can gait is popular in clinical practice; however, it needs to be documented. be considered that the reliability of such visual obser- vations is, at best, moderate,105 and that walking pat- When undertaking such assessments, however, it terns on a treadmill may differ from normal overground needs to be kept in mind that the pressure distribu- walking.106 Furthermore, some older people may find tion under the foot is dependent on a wide range of treadmill walking very difficult because of balance factors, including walking speed, step length, body- problems. A recent study of healthy older people weight, foot deformity and the degree of peripheral assessed the time required to become familiarised to sensory loss.65 Because of this complexity, extrapolat- treadmill walking, by comparing temporospatial char- ing foot motion characteristics (such as the degree of acteristics and sagittal plane kinematics of the knee to foot pronation) from plantar pressure recordings is overground walking. After 15 minutes of treadmill difficult. While it appears that foot pronation does walking, two-thirds of the sample still required the result in greater medial loading of the midfoot in support of the handrails, and knee kinematics and older people, forefoot pressures are more closely cor- cadence did not reflect overground walking values.107 related to the degree of hallux valgus deformity and These findings suggest that gait assessments using the available range of motion in the first metatarso- treadmills may be of limited value in older people. phalangeal joint.65 Examples of foot pressure record- ings from older people are shown in Figure 3.12 and Assessment of plantar pressure patterns is useful for a summary of the strongest clinical predictors of identifying areas of high pressure that may predispose plantar forces in older people in Figure 3.13. to plantar calluses and ulceration. The simplest tech- nique is the Harris & Beath mat,108 a rubber platform FALLS RISK ASSESSMENT with three layers of ridges that is covered with a thin layer of ink and a sheet of paper. When the patient Community-based studies indicate that one in three walks over the mat, high pressure areas appear more people aged over 65 years will fall in any given year. densely inked because of the compression of the mat Falls frequently result in injury and are the leading to the lower level of ridges. The Harris & Beath mat cause of injury-related death in older people.113 The is a very useful clinical tool for documenting foot role and scope of podiatry in falls prevention is poorly shape and identifying high pressure areas;109 however, defined but is gaining considerable attention in the data obtained from the system can only be con- response to recent studies indicating that foot prob- sidered to be semi-quantitative, despite attempts to lems (including foot pain, hallux valgus, decreased calibrate the outputs to known forces.110 A similar ankle flexibility, peripheral sensory loss and toe plan- low-cost system uses carbon paper sheets, which tarflexor weakness) are independent risk factors for record varying levels of grey when pressure is applied. falling.68 Given these observations, it is likely that Using a calibration card, the pressure recording can most older people attending foot-care specialists have be documented in a quantitative manner. A study an elevated risk of falling compared to the general comparing pressures obtained using this technique to elderly population. However, documenting medical an optical pedobarograph indicated that the carbon conditions that are strong risk factors for falling and paper prints provide a sensitive measure of peak undertaking some simple clinical tests will provide plantar pressures, provided that clinicians undergo more accurate identification of very-high-risk older sufficient training in applying the technique.111 people who are most likely to benefit from falls pre- vention activities. Table 3.15 describes some simple More recently, several plantar pressure systems tests that have been shown to be useful predictors of based on resistive or capacitive sensor technology falls.114–117 Footwear evaluation also plays a role in falls have become commercially available, either as plat- risk assessment (see Footwear assessment, below). form-based systems or in the form of insoles placed inside the shoe.112 Although the cost of many of these

52 ASSESSMENT Figure 3.12 Examples of foot pressure recordings from older people. A. Hallux limitus. B. Tibialis posterior dysfunction. C. Severe hallux valgus deformity and associated plantar lesions. D. Pes cavus foot type. Paper grip test H (0.32)** 13 Bodyweight (0.36)* of older patients to maintain adequate foot hygiene 1st MPJ ROM (-0.26)** Ankle flexibility (0.20)* and undertake basic foot-care tasks, such as cutting Hallux valgus (-0.21)** 37 and filing nails, applying emollient creams, wash- + age (-0.20)** ing and drying feet, managing areas of dry skin and calluses, putting on shoes and hosiery, inspecting the Bodyweight (0.53)** 42 39 42 foot for lesions and changing wound dressings. Failure 1st MPJ ROM (0.14)** to adequately assess an older person’s competence to perform these tasks can have serious ramifications, Bodyweight (0.48)** particularly in older people with peripheral vascular disease or diabetes. Bodyweight (0.35)** Undertaking basic foot care is inherently difficult 53 Arch index (0.61)** for older people, as it requires not only adequate joint Bodyweight (0.36)** flexibility but also a high level of manual dexterity and visual acuity, all of which decline with advancing age. 39 Bodyweight (0.58)** A particularly good example of the importance of Ankle flexibility (0.19)** assessing basic foot-care competence was provided by Thomson & Masson,118 who evaluated the ability of Figure 3.13 Determinants of plantar forces in older older people with and without diabetes to reach down people. Values displayed in mask regions represent r 2 to their feet to inspect a ‘virtual lesion’ – an adhesive values, and values contained in brackets represent β- red spot placed on the toes or on the plantar surface weights for each significant independent (‘predictor’) of the foot. The results indicated that 39% of those variable. *significance of β-weight p < 0.05, with diabetes could not reach their toes, and only 14% **significance of β-weight p < 0.01. MPJ, of all older participants could detect the plantar metatarsophalangeal joint; ROM, range of movement. ‘lesions’. It is therefore clear that advising older people to undertake basic foot-care tasks is not helpful unless ASSESSMENT OF THE ABILITY TO they are actually capable of performing the task. PERFORM BASIC FOOT CARE Evaluating self-management ability can be under- Many clinical interventions require the patient to taken during a routine consultation by simply observ- undertake some level of self-management of their foot ing whether the patient is capable of removing their problem in the household environment. For this footwear and whether they have sufficient flexibility reason, foot specialists need to be aware of the ability to reach and indicate the location of the foot problem. Assessing other aspects of self-management, such as using nail files, changing dressings and applying emol- lients, may require the clinician to specifically request

Footwear assessment 53 Table 3.15 Clinical mobility tests that can be used to predict risk of falling Test Description Cut-off score that indicates increased risk of falling Unipedal stance Measurement of the time (in seconds) that an individual <30 s Functional reach test can stand on one leg unsupported <15 cm Walking speed <0.56 m/s Timed up and go test Measurement of the distance that an individual can >14 s reach forward without moving their feet Measurement of the time taken to walk a certain fixed distance (usually 6 m) Measurement of the time taken to stand from a chair, walk 3 m, turn around and sit back down that the patient demonstrate these skills. Assistive Fixation devices (such as long-handled shoe horns, nail files and devices to assist with footwear fixation) should Heel Depth of toe-box also be available and demonstrations provided to counter patients who may benefit from them. flexibility Shoe length and width FOOTWEAR ASSESSMENT Heel Sole flexion point height Sole slip resistance Evaluation of footwear is one of the most fundamen- tal components of lower limb assessment in older Sole hardness people. It has been demonstrated that between 50 and flexibility and 80% of older people wear ill-fitting shoes119,120 and there is evidence that the constriction associated Figure 3.14 Key components of footwear evaluation in with tightly fitting shoes predisposes to the develop- older people. ment of common foot problems. Menz & Morris121 recently evaluated footwear fitting in 176 older people efficacy of these interventions is highly dependent on and found that 80% wore shoes narrower than their the ability of the shoes to support and facilitate the feet. Those who wore shoes narrower than their feet function of these devices. were more likely to have corns on the toes, hallux valgus deformity and foot pain, whereas those who The first issue to consider when assessing footwear wore shoes shorter than their feet were more likely to is whether the shoes that the older person is wearing have lesser toe deformity. Heel elevation in women’s at the time of the consultation are those that are worn shoes was associated with both hallux valgus and most frequently – in many cases the shoes worn may plantar calluses. be ‘dress shoes’ only worn for special occasions (such as attending medical appointments). It is also impor- Because of the strong association between ill-fitting tant to ensure that indoor footwear is also assessed, footwear and foot problems, footwear evaluation is an as some older people may spend more of their time essential first step in investigating the potential causes indoors than outdoors. Although indoor shoes are of foot problems. Indeed, changing footwear may be generally wider fitting than outdoor shoes,121 they the only intervention necessary to successfully manage also tend to be less supportive and are replaced far many common foot problems, particularly those less frequently.122 Key features of footwear that should related to toe deformities and associated hyperkera- be routinely assessed in older people are summarised totic lesions. Footwear also needs to be evaluated for in Figure 3.14. suitability in relation to the provision of toe splints, in-shoe plantar padding and foot orthoses, as the Assessment of shoe fit should be performed while the patient is standing, in order to accurately capture the elongation of the foot and lateral expansion of soft tissues of the forefoot123 and heel124 that occurs during weightbearing. The time of day may also need to be considered, as, although foot volume does not appreciably change throughout the day in healthy

54 ASSESSMENT ABCD 11 16 1 17 12 18 2 13 19 3 20 4 14 21 5 15 22 23 6 16 24 7 17 25 8 18 26 9 27 19 28 10 29 11 20 30 12 21 31 13 15 Figure 3.16 Typical example of a shoe and foot tracing 32 from an older woman. 22 33 1 25 the patient’s bare foot on a piece of paper, and using the same piece of paper to trace around their shoe 23 34 2 35 (Fig. 3.16). The depth of the shoe is of equal impor- tance to its length and width, particularly because the 24 35 3 45 depth of a shoe does not increase as shoe size increases. 36 4 55 This aspect of shoe fit is more difficult to accurately measure; however, careful observation and palpation 25 37 5 65 of the shoe will enable the identification of deformed 38 or stretched areas of the upper caused by toe deformities. 26 39 6 75 Assessing the wear patterns of footwear may provide 27 40 7 85 useful diagnostic information regarding foot structure and function.126 Excessive medial or lateral wear marks 28 41 8 95 on the sole may indicate a pes planus or pes cavus foot 42 type, while deformation and creasing of the toe box 29 43 9 105 of the shoe may indicate hallux valgus or hallux 44 10 115 limitus. However, wear patterns are also influenced by bodyweight, the mechanical properties of materials 30 45 11 125 the shoe is manufactured from, how long the shoe has been worn for and the level of physical activity of 31 46 12 135 the wearer and these observations therefore need to 47 be interpreted with a certain degree of caution. 32 48 13 Finally, the inside of the shoe should always be examined for evidence of exposed seams or foreign Figure 3.15 Shoe length conversion chart. bodies (particularly in older people with peripheral A. Centimetres. B. Paris points. C. English sizing neuropathy), as even minor irregularities may contrib- system. D. American women’s sizes. ute to the development of skin lesions. Indeed, a study of 669 people presenting with foot ulcers at young adults,125 prolonged standing and weightbear- a diabetes clinic in the UK indicated that the most ing activity may influence the volume of the foot in commonly reported trigger event was friction from older people, particularly those with venous insuffi- footwear.127 ciency. Foot length (from heel to longest toe) and width (at the level of the forefoot) measurements can be taken with a ruler (or Brannock device) and the measurements converted to shoe size measures using a conversion chart (Fig. 3.15). As a general rule, the shoe should be approximately 12 mm longer than the longest toe. It may be also useful to provide patients with a visual indication of the disparity between their foot size and their shoe size. This can be very simply and effectively demonstrated by making a tracing of

Assessing outcomes of treatment 55 General shoe style/covering socks only stockings only backless slipper barefoot high heel court shoe boot mule sandal moccasin athletic shoe slipper Oxford shoe ugg boot thong walking shoe surgical/bespoke footwear zips Heel height 2.6 – 5.0 cm > 5.0 cm fully worn 0–2.5 cm straps/buckles >45° Fixation laces >45° Velcro™ none Heel counter stiffness <45° minimal Longitudinal sole rigidity <45° minimal Sole flexion point before MTPJs at level of MTPJs Tread pattern smooth (i.e. no pattern) partly worn textured Sole hardness firm hard soft Figure 3.17 The Footwear Assessment Form. FOOTWEAR AND FALLS and complete resolution of the condition is not always possible. For example, while the effectiveness of An additional consideration when assessing footwear orthotic therapy for an acute episode of heel pain in in older people is their potential contribution to a young person may be adequately assessed using a impaired balance and falls. Certain footwear charac- simple visual analogue pain scale, the effectiveness of teristics, such as high heels, soles with poor grip and ongoing ‘maintenance’ treatments for chronic kera- inadequate fixation, have been associated with totic lesions associated with fixed deformities is more impaired gait, balance, falls and hip fracture (Ch. 12). difficult to quantify. The value of ongoing mainte- A standardised screening tool – the Footwear Assess- nance, however, should not be underestimated, as ment Form – has been developed for the purpose of recent studies have demonstrated that significant assessing footwear in relation to balance and falls (Fig. declines in foot health occur when older people are 3.17).128 Patients with a history of falls whose foot- discharged from ‘routine’ podiatry services.129 wear exhibits multiple potentially hazardous features should be advised to consider the purchase of more Despite the difficulties in quantifying outcomes in appropriate shoes. The role of footwear in falls is dis- older people, some form of outcome assessment is cussed in more detail in Chapter 12. useful to assist in formalising the goals of treatment. The best approach is to involve the patient as much as ASSESSING OUTCOMES OF TREATMENT possible by asking them what they hope to achieve from the treatment. Patient expectations of treatment Assessing the effectiveness of clinical treatments in may include a reduction in (or complete resolution of) older people can be difficult. In many cases the end- pain, reduction in the size or complete healing of a point is not clearly defined, as older people generally foot ulcer, prevention of skin breakdown or infection, present with multiple presenting complaints, the maintenance of adequate foot hygiene or maintenance underlying conditions responsible for these com- of mobility (e.g. being able to walk to shops without plaints have been present for a long period of time, pain or limitation). By matching patient expectations of treatment to some form of outcome measure, the

56 ASSESSMENT assessment process can be made more meaningful for people, and the clinical examination should be equally both the patient and clinician and progress in achiev- thorough and systematic. Key additional consider- ing the treatment goal can be more easily documented. ations when assessing older people include the vari- In addition to the previously discussed pain scales and ability of the ageing process, the multifactorial nature functional tests, other tools, such as pain diaries and of foot disorders in older people and the broader wound measurement charts, may also be useful for implications of mobility impairment. The clinical assessing treatment outcomes. assessment techniques outlined in this chapter will assist clinicians in the accurate diagnosis of lower limb SUMMARY disorders and contribute to the development of tar- geted and effective management strategies for older The general principles of lower limb assessment in people. older people are essentially the same as for younger References sity scales in younger and older surgical patients. Pain 2005; 117: 412–420. 1. Tinetti ME. Approach to clinical care of the older 11. Budiman-Mak E, Conrad KJ, Roach KE. The Foot patient. In: Hazzard WR, Blass JP, Halter JB et al, Function Index: a measure of pain and disability. eds. Principles of geriatric medicine and gerontol- Journal of Clinical Epidemiology 1991; 44: 561– ogy. New York: McGraw-Hill; 2003: 95–110. 570. 12. Bennett P, Patterson C, Wearing S et al. Develop- 2. Kaufman DW, Kelly JP, Rosenberg L et al. Recent ment and validation of a questionnaire designed to patterns of medication use in the ambulatory adult measure foot-health status. Journal of the American population of the United States: the Slone survey. Podiatric Medical Association 1998; 88: 419–428. Journal of the American Medical Association 2002; 13. Kitaoka HB, Alexander IJ, Adelaar RS et al. Clinical 287: 337–344. rating systems for the ankle-hindfoot, midfoot, hallux, and lesser toes. Foot and Ankle International 3. Eisenberg DM, Kessler RC, Foster C et al. Uncon- 1994; 15: 349–353. ventional medicine in the United States. Prevalence, 14. Garrow AP, Papageorgiou AC, Silman AJ et al. costs, and patterns of use. New England Journal of Development and validation of a questionnaire to Medicine 1993; 328: 246–252. assess disabling foot pain. Pain 2000; 85: 107– 113. 4. Izzo AA, Ernst E. Interactions between herbal medi- 15. Barnett S, Campbell R, Harvey I. The Bristol Foot cines and prescribed drugs: a systematic review. Score: developing a patient-based foot-health Drugs 2001; 61: 2163–2175. measure. Journal of the American Podiatric Medical Association 2005; 95: 264–272. 5. Ernst E. The risk-benefit profile of commonly used 16. Menz HB, Tiedemann A, Kwan MMS et al. Foot herbal therapies: gingko, St John’s wort, ginseng, pain in community-dwelling older people: an evalu- echinacea, saw palmetto, and kava. Annals of Inter- ation of the Manchester Foot Pain and Disability nal Medicine 2002; 136: 42–53. Index. Rheumatology 2006; 45: 863–867. 17. Waxman R, Woodburn H, Powell M et al. FOOT- 6. Folstein MF, McHugh PR. Mini-Mental State: a STEP: a randomized controlled trial investigating practical method for grading the state of patients for the clinical and cost effectiveness of a patient self- the clinician. Journal of Psychiatric Research 1975; management program for basic foot care in the 12: 189–198. elderly. Journal of Clinical Epidemiology 2003; 56: 1092–1099. 7. Shulman KI. Clock-drawing: is it the ideal cognitive 18. Herr K, Bjoro K, Decker S. Tools for assessment of screening test? International Journal of Geriatric pain in nonverbal older adults with dementia: a Psychiatry 2000; 15: 548–561. state-of-the-science review. Journal of Pain and Symptom Management 2006; 31: 170–192. 8. Shua-Haim J, Koppuzha G, Gross J. A simple scoring system for clock drawing in patients with Alzheim- er’s disease. Journal of the American Geriatrics Society 1996; 44: 335. 9. Melzack R. The McGill Pain Questionnaire: major properties and scoring methods. Pain 1975; 1: 277–299. 10. Gagliese L, Weizblit N, Ellis W et al. The measure- ment of post-operative pain: a comparison of inten-

References 57 19. Rogers RS, Callen J, Wehr R et al. Comparative 33. Khan NA, Rahim SA, Anand SS et al. Does the clini- efficacy of 12% ammonium lactate lotion and 5% cal examination predict lower extremity peripheral lactic acid lotion in the treatment of moderate to arterial disease? Journal of the American Medical severe xerosis. Journal of the American Academy of Association 2006; 295: 536–546. Dermatology 1989; 21: 714–716. 34. Donnelly R, Hinwood D, London NJM. Non- 20. Lee CM, Maibach HI. Bioengineering analysis of invasive methods of arterial and venous assess- water hydration: an overview. Exogenous Dermatol- ment. British Medical Journal 2000; 320: 698– ogy 2002; 1: 269–275. 701. 21. Jennings MB, Alfieri D, Ward K et al. Comparison 35. Yao JS. New techniques in objective arterial evalua- of salicylic acid and urea versus ammonium lactate tion. Archives of Surgery 1973; 106: 600–604. for the treatment of foot xerosis. A randomized, double-blind, clinical study. Journal of the American 36. Jelinek HF, Austin M. The ankle-brachial index in Podiatric Medical Association 1998; 88: 332– clinical decision making. The Foot 2006; 16: 153– 336. 157. 22. Scherer WP, McCreary JP, Hayes WW. The diagno- 37. Sacks D, Bakal CW, Beatty PT et al. Position state- sis of onychomycosis in a geriatric population: a ment on the use of the ankle brachial index in the study of 450 cases in South Florida. Journal of the evaluation of patients with peripheral vascular American Podiatric Medical Association 2001; 91: disease. A consensus statement developed by the 456–464. Standards Division of the Society of Interventional Radiology. Journal of Vascular Interventional Radi- 23. Lemon B, Burns R. Malignant melanoma: a litera- ology 2003; 14: S389. ture review and case presentation. Journal of Foot and Ankle Surgery 1998; 37: 48–54. 38. Smith FCT, Shearman CP, Simms MH et al. Falsely elevated ankle pressures in severe leg ischaemia: the 24. Wagner FW. The diabetic foot. Orthopedics 1987; pole test – an alternative approach. European Journal 10: 163–172. of Vascular Surgery 1994; 8: 408–412. 25. Oyibo SO, Jude EB, Tarawneh I et al. A comparison 39. Carpentier PH, Maricq HR, Biro C et al. Prevalence, of two diabetic foot ulcer classification systems. The risk factors, and clinical patterns of chronic venous Wagner and the University of Texas wound classifi- disorders of lower limbs: a population-based study cation systems. Diabetes Care 2001; 24: 84–88. in France. Journal of Vascular Surgery 2004; 40: 650–659. 26. Selvin E, Erlinger TP. Prevalence of and risk factors for peripheral arterial disease in the United States. 40. Rosher RB, Robinson SB. Use of foot veins to Results from the National Health and Nutrition monitor hydration in the elderly. Journal of the Examination Survey, 1999–2000. Circulation 2004; American Geriatrics Society 2004; 52: 322–324. 110: 738–743. 41. Wells PS, Hirsh J, Anderson DR et al. Accuracy of 27. Kuller LH. Is ankle-brachial blood pressure mea- clinical assessment of deep-vein thrombosis. The surement of clinical utility for asymptomatic elderly? Lancet 1995; 345: 1326–1330. Journal of Clinical Epidemiology 2001; 54: 971– 972. 42. Tovey C, Wyatt S. Diagnosis, investigation, and management of deep vein thrombosis. British 28. Lawson G. The importance of obtaining ankle-bra- Medical Journal 2003; 326: 1180–1184. chial indexes in older adults: the other vital sign. Journal of Vascular Nursing 2005; 23: 46–51. 43. Lensing AWA, Brandoni P, Buller HR et al. Lower extremity venography with iohexol: results and com- 29. Fontain R, Kim M, Kieny R. Die chirurgische plications. Radiology 1990; 77: 503–505. Behandlung der peripheren Durchblutungsstorun- gen. Helvetia Chirurgica Acta 1954; 5/6: 499– 44. Kraaijenhagen RA, Lensing AW, Wallis JW et al. 533. Diagnostic management of venous thromboembo- lism. Baillières Clinical Haematology 1998; 11: 30. Leng GC, Fowkes FG. The Edinburgh Claudication 541–586. Questionnaire: an improved version of the WHO/ Rose Questionnaire for use in epidemiological 45. Franse LV, Valk GD, Dekker JH et al. ‘Numbness surveys. Journal of Clinical Epidemiology 1992; 45: of the feet’ is a poor indicator for polyneuropathy in 1101–1109. Type 2 diabetic patients. Diabetic Medicine 2000; 17: 105–110. 31. Pedrini L. Critical ischaemia of the lower limbs: diagnostic and therapeutic strategies. Foot and Ankle 46. Bowditch MG, Sanderson P, Livesey JP. The signifi- Surgery 2003; 9: 87–94. cance of an absent ankle reflex. Journal of Bone and Joint Surgery 1996; 78B: 276–279. 32. McGee SR, Boyko EJ. Physical examination and chronic lower-extremity ischaemia: a critical review. 47. Prakash C, Stern G. Neurological signs in the elderly. Archives of Internal Medicine 1998; 158: 1357– Age and Ageing 1973; 2: 24–27. 1364. 48. Richardson J. The clinical identification of peri- pheral neuropathy among older persons. Archives

58 ASSESSMENT of Physical Medicine and Rehabilitation 2002; 83: 63. Mueller MJ, Host JV, Norton BJ. Navicular drop as 1553–1558. a composite measure of excessive pronation. Journal 49. Scott G, Menz HB, Newcombe L. Age-related dif- of the American Podiatric Medical Association 1993; ferences in foot structure and function. Gait and 83: 198–202. Posture 2007; 26: 68–75. 50. Garrow AP, Papageorgiou A, Silman AJ et al. The 64. Menz HB, Munteanu SE. Validity of three clinical grading of hallux valgus. The Manchester Scale. techniques for the measurement of static foot posture Journal of the American Podiatric Medical Associa- in older people. Journal of Orthopaedic and Sports tion 2001; 91: 74–78. Physical Therapy 2005; 35: 479–486. 51. Menz HB, Munteanu SE. Radiographic validation of the Manchester scale for the classification of hallux 65. Menz HB, Morris ME. Clinical determinants of valgus deformity. Rheumatology 2005; 44: 1061– plantar forces and pressures during walking in older 1066. people. Gait and Posture 2006; 24: 229–236. 52. Spooner SK, Kilmartin TE, Merriman LM. The pal- pation technique for determination of metatarsal 66. Menz HB, Morris ME, Lord SR. Foot and ankle formula: a study of validity. The Foot 1994; 4: characteristics associated with impaired balance and 198–200. functional ability in older people. Journal of Geron- 53. Root ML, Orien WP, Weed JH. Clinical Biome- tology 2005; 60A: 1546–1552. chanics, vol 2. Normal and abnormal function of the foot. Los Angeles, CA: Clinical Biomechanics Cor- 67. Menz HB, Tiedemann A, Kwan MMS et al. Reli- poration; 1977. ability of clinical tests of foot and ankle characteris- 54. McPoil TG, Hunt GC. Evaluation and management tics in older people. Journal of the American Podiatric of foot and ankle disorders: present problems and Medical Association 2003; 93: 380–387. future directions. Journal of Orthopaedic and Sports Physical Therapy 1995; 21: 381–388. 68. Menz HB, Morris ME, Lord SR. Foot and ankle risk 55. Razeghi M, Batt ME. Foot type classification: a criti- factors for falls in older people: a prospective study. cal review of current methods. Gait and Posture Journal of Gerontology 2006; 61A: M866–M870. 2002; 15: 282–291. 56. Cowan DN, Robinson JR, Jones BH. Consistency 69. Menz HB. Clinical hindfoot measurement: a critical of visual assessment of arch height among clinicians. review of the literature. The Foot 1995; 5: 57–64. Foot and Ankle International 1994; 15: 213– 217. 70. Menadue C, Raymond J, Kilbreath SL et al. Reli- 57. Dahle LK, Mueller M, Delitto A et al. Visual assess- ability of two goniometric methods of measuring ment of foot type and relationship of foot type to active inversion and eversion range of motion at the lower extremity injury. Journal of Orthopaedic and ankle. BMC Musculoskeletal Disorders 2006; 7: 60. Sports Physical Therapy 1991; 14: 70–74. 58. Redmond AC, Crosbie J, Ouvrier RA. Development 71. Perry J, Ireland ML, Gronley J et al. Predictive value and validation of a novel rating system for scoring of manual muscle testing and gait analysis in normal standing foot posture: the Foot Posture Index. Clin- ankles by dynamic electromyography. Foot and ical Biomechanics 2006; 21: 89–98. Ankle 1986; 6: 254–259. 59. Cavanagh PR, Rodgers MM. The arch index: a useful measure from footprints. Journal of Biome- 72. Kendall HO, Kendall FP. Muscles: testing and func- chanics 1987; 20: 547–551. tion. Baltimore, MD: Williams & Wilkins; 1949. 60. Staheli LT, Chew DE, Corbett M. The longitudinal arch. A survey of eight hundred and eighty-two feet 73. DeWin M, Theuvenet W, Roche P et al. The paper in normal children and adults. Journal of Bone and grip test for screening of intrinsic muscle paralysis in Joint Surgery 1987; 69A: 426–428. the foot of leprosy patients. International Journal of 61. Picciano AM, Rowlands MS, Worrell T. Reliability Leprosy and other Mycobacterial Diseases 2002; 70: of open and closed kinetic chain subtalar joint neutral 16–24. positions and navicular drop test. Journal of Ortho- paedic and Sports Physical Therapy 1993; 18: 74. Menz HB, Zammit GV, Munteanu SE et al. Plan- 553–558. tarflexion strength of the toes: age and gender dif- 62. Sell K, Verity TM, Worrell TW et al. Two measure- ferences and evaluation of a clinical screening test. ments techniques for assessing subtalar joint posi- Foot and Ankle International 2006; 27: 1103– tion: a reliability study. Journal of Orthopaedic and 1108. Sports Physical Therapy 1994; 19: 162–167. 75. Bohannon RW. Intertester reliability of hand-held dynamometry: a concise summary of published research. Perceptual and Motor Skills 1999; 88: 899–902. 76. Burns J, Redmond A, Ouvrier R et al. Quantification of muscle strength and imbalance in neurogenic pes cavus, compared to healthy controls, using hand- held dynamometry. Foot and Ankle International 2005; 26: 540–544. 77. Ory PA. Radiography in the assessment of musculo- skeletal conditions. Best Practice and Research Clini- cal Rheumatology 2003; 17: 495–512.

References 59 78. Christman RA. Radiologic aspects of aging in the 95. Katz S, Downs TD, Crash H et al. Progress in devel- foot. Clinics in Podiatric Medicine and Surgery opment of the index of ADL. Gerontologist 1970; 1993; 10: 97–112. 10: 20–30. 79. Calleja M, Alam A, Wilson D et al. Basic science: 96. Mahoney FI, Barthel DW. Functional evaluation: nuclear medicine in skeletal imaging. Current Ortho- the Barthel index. Maryland State Medical Journal paedics 2005; 19: 34–39. 1965; 14: 61–65. 80. Hendler A, Hershkop M. When to use bone scin- 97. Rozzini R, Sabatini T, Cassinadri A et al. Relation- tigraphy. Postgraduate Medicine 1998; 104: 54– ship between functional loss before hospital admis- 72. sion and mortality in elderly persons with medical illness. Journal of Gerontology 2005; 60A: M1180– 81. Varenna M, Binelli L, Zucchi F et al. Is the meta- M1183. tarsal fracture in postmenopausal women an osteo- porotic fracture? A cross-sectional study on 113 98. Tiedemann A, Sherrington C, Lord SR. Physiologi- cases. Osteoporosis International 1997; 7: 558– cal and psychological predictors of walking speed in 563. older community-dwelling people. Gerontology 2005; 51: 390–395. 82. Freeman D, Randall D. Stress fracture of the foot secondary to osteoporosis: an atypical presentation. 99. Woo J, Ho SC, Yu AL. Walking speed and stride Journal of the American Podiatric Medical Associa- length predicts 36 months dependency, mortality, tion 2001; 91: 99–101. and institutionalization in Chinese aged 70 and older. Journal of the American Geriatrics Society 83. Kaye R. Insufficiency stress fractures of the foot and 1999; 47: 1257–1260. ankle in postmenopausal women. Foot and Ankle International 1988; 19: 221–224. 100. Menz HB, Lord SR. The contribution of foot prob- lems to mobility impairment and falls in older people. 84. Umans H, Pavlov H. Insufficiency fracture of the Journal of the American Geriatrics Society 2001; 49: talus: diagnosis with MR imaging. Radiology 1995; 1651–1656. 197: 439–442. 101. Ostchega Y, Harris TB, Hirsch R et al. The preva- 85. Ito K, Hori K, Terashima Y et al. Insufficiency frac- lence of functional limitations and disability in older ture of the body of the calcaneus in elderly patients persons in the US: data from the National Health with osteoporosis. Clinical Orthopaedics and Related and Nutrition Examination Survey III. Journal Research 2004; 422: 190–194. of the American Geriatrics Society 2000; 48: 1132–1135. 86. O’Duffy EK, Clunie RPR, Gacinovic S et al. Foot pain: specific indications for scintigraphy. 102. Oberg T, Karsznia A, Oberg K. Basic gait parame- British Journal of Rheumatology 1998; 37: 442– ters: reference data for normal subjects, 10–79 years 447. of age. Journal of Rehabilitation Research and Development 1993; 30: 210–223. 87. Colquhoun K, Alam A, Wilson D. Basic science: ultrasound. Current Orthopaedics 2005; 19: 27– 103. Alexander NB, Goldberg A. Gait disorders: search 33. for multiple causes. Cleveland Clinic Journal of Medicine 2005; 72: 586–600. 88. Fessell DP, VanHolsbeeck MT. Foot and ankle sonography. Radiologic Clinics of North America 104. Studenski S, Perera S, Wallace D et al. Physical per- 1999; 37: 831–858. formance measures in the clinical setting. Journal of the American Geriatrics Society 2003; 51: 314– 89. Koski JM. Ultrasound guided injections in rheuma- 322. tology. Journal of Rheumatology 2000; 27: 2131– 2138. 105. Keenan A, Bach T. Video assessment of rearfoot movements during walking: a reliability study. 90. Barron D. Basic science: computed tomography. Archives of Physical Medicine and Rehabilitation Current Orthopaedics 2005; 19: 20–26. 1996; 77: 651–655. 91. Balint G, Korda J, Hangody L et al. Foot and ankle 106. Marsh AP, Katula JA, Pacchia CF et al. Effect of disorders. Best Practice and Research Clinical Rheu- treadmill and overground walking on function and matology 2003; 17: 87–111. attitudes in older adults. Medicine and Science in Sports and Exercise 2006; 38: 1157–1164. 92. McKie S, Brittenden J. Basic science: magnetic reso- nance imaging. Current Orthopaedics 2005; 19: 107. Wass E, Taylor NF, Matsas A. Familiarisation to 13–19. treadmill walking in unimpaired older people. Gait and Posture 2005; 21: 72–79. 93. Rosenberg ZS, Beltran J, Bencardino JT. MR imaging of the ankle and foot. Radiographics 2000; 108. Harris RI, Beath T. Army foot survey. An investiga- 20: S153–179. tion of foot ailments in Canadian soldiers. Ottawa: National Research Council, Canada NRC no. 1574; 94. Ashman CJ, Klecker RJ, Yu JS. Forefoot pain involv- 1947. ing the metatarsal region: differential diagnosis with MR imaging. Radiographics 2001; 21: 1425– 1440.

60 ASSESSMENT 109. Welton EA. The Harris and Beath footprint: inter- 120. Burns S, Leese G, McMurdo M. Older people and pretation and clinical value. Foot and Ankle 1992; ill-fitting shoes. Postgraduate Medical Journal 2002; 13: 462–468. 78: 344–346. 110. Silvino N, Evanski PM, Waugh TR. The Harris and 121. Menz HB, Morris ME. Footwear characteristics and Beath mat: diagnostic validity and clinical use. Clini- foot problems in older people. Gerontology 2005; cal Orthopaedics and Related Research 1980; 151: 51: 346–351. 265–269. 122. Munro BJ, Steele JR. Household-shoe wearing and 111. VanSchie CH, Abbott CA, Vileikyte L et al. A com- purchasing habits – a survey of people aged 65 years parative study of the Podotrack, a simple semiquan- and older. Journal of the American Podiatric Medical titative plantar pressure measuring device, and the Association 1999; 89: 506–514. optical pedobarograph in the assessment of pressures under the diabetic foot. Diabetic Medicine 1999; 123. Weijers RE, Walenkamp GHIM, VanMameren H et 16: 154–159. al. Changes in the soft tissue of the forefoot during loading: a volumetric study. The Foot 2003; 13: 112. Orlin M, McPoil T. Plantar pressure assessment. 70–75. Physical Therapy 2000; 80: 399–409. 124. Fuller E, Hogge JD. Measurement of the expansion 113. Lord SR, Sherrington C, Menz HB, Close JC. Falls of the calcaneal fat pad upon weightbearing. Journal in older people: risk factors and strategies for pre- of the American Podiatric Medical Association 1998; vention, 2nd ed. Cambridge: Cambridge University 88: 12–16. Press; 2007. 125. Moholkar K, Fenelon G. Diurnal variations in 114. Duncan PW, Studenski S, Chandler J et al. Func- volume of the foot and ankle. Journal of Foot and tional reach: predictive validity in a sample of elderly Ankle Surgery 2001; 40: 302–304. male veterans. Journal of Gerontology 1992; 47: M93–98. 126. Vernon W, Parry A, Potter M. A theory of shoe wear pattern influence incorporating a new paradigm for 115. VanSwearingen JM, Paschal KA, Bonino P et al. the podiatric medical profession. Journal of the Assessing recurrent fall risk of community-dwelling, American Podiatric Medical Association 2004; 94: frail older veterans using specific tests of mobility 261–268. and the Physical Performance Test of function. Journal of Gerontology 1998; 53A: M457–M464. 127. Macfarlane RM, Jeffcoate WJ. Factors contributing to the presentation of diabetic foot ulcers. Diabetic 116. Shumway-Cook A, Brauer S, Woollacott M. Predict- Medicine 1997; 14: 867–870. ing the probability for falls in community-dwelling older adults using the Timed Up & Go Test. Physi- 128. Menz HB, Sherrington C. The Footwear Assess- cal Therapy 2000; 80: 896–903. ment Form: a reliable clinical tool for the evaluation of footwear characteristics of relevance to postural 117. Hurvitz E, Richardson J, Werner R et al. Unipedal stability in older adults. Clinical Rehabilitation 2000; stance testing as an indicator of fall risk among older 14: 657–664. outpatients. Archives of Physical Medicine and Rehabilitation 2000; 81: 587–591. 129. Campbell J, Patterson A, Gregory D et al. What happens when older people are discharged from 118. Thomson FJ, Masson EA. Can elderly diabetic NHS podiatry services? The The Foot 2002; 12: patients co-operate with routine foot care? Age and 32–42. Ageing 1992; 21: 333–337. 119. Chung S. Foot care – a health care maintenance program. Journal of Gerontological Nursing 1983; 9: 213–227.

Keratotic disorders CHAPTER 4 CHAPTER CONTENTS Keratotic lesions are one of the most prevalent foot problems in older people, affecting between 20% and Classification and clinical presentation 61 65% of people over 65 years of age.1–7 Although often Aetiology 62 considered a relatively minor complaint, keratotic lesions can cause considerable pain and disability. It Assessment and diagnosis 67 has been demonstrated that older people with plantar keratotic lesions have greater difficulty walking on Treatment 69 level ground and ascending and descending stairs, and Conservative treatments 69 perform worse in tests of balance ability.8 Further- Surgical treatment 72 more, if left untreated, keratotic lesions may cause damage to deeper tissues and lead to ulceration.9 Summary 74 Therefore, the accurate diagnosis and management of References 74 keratotic disorders is an essential component of foot care for older people. CLASSIFICATION AND CLINICAL PRESENTATION There are two main types of keratotic lesion – calluses and corns (Table 4.1). Calluses (also known as tylomas, callosities and keratomas) present as a broad-based, diffuse thickening of the stratum corneum and are most commonly located under the metatarsal heads (Fig. 4.1). Calluses vary in colour from white to grey- yellow; however, they may also occasionally appear brown or red because of extravasation of blood in the underlying dermis. Calluses under the metatarsal heads have a characteristic topography that may reflect differences in weightbearing patterns under the foot when walking. Merriman et al10 evaluated lesion pat- terns in 243 chiropody patients and found that the most common presentation was under the second to fourth metatarsal heads, followed by the second

62 KERATOTIC DISORDERS Table 4.1 Classification of keratotic lesions Lesion Alternative terminology Subtypes Common locations Callus Tyloma – Plantar metatarsal heads Corn Callosity Periphery of heel Keratoma Hard corn (heloma durum) Dorsal interphalangeal joints Intractable plantar keratoma • Vascular (heloma vasculare) Apices of toes • Neurovascular (heloma neurovasculare) Helomata • Fibrous (heloma fascia) Dorsal interphalangeal joints Clavus Soft corn (heloma molle) Apices of toes Seed corn (heloma milliare) Plantar metatarsal heads Interdigital Non-weightbearing areas of plantar surface Figure 4.1 Callus on the plantar aspect of the central Corns (also known as heloma or clavi) are a more metatarsal heads. (Courtesy of Lloyd Reed, Queensland discrete, circumscribed area of thickening with a University of Technology.) central core that may penetrate into the dermis.13 Three subtypes of corn have been recognised: hard metatarsal head (Fig. 4.2). Similar observations were corns (heloma dura), soft corns (heloma molle) and reported by Springett et al11 and Grouios,12 who seed corns (heloma milliare). The distribution pat- found the most common presentation to be the terns of these lesions vary (Fig. 4.3). Hard corns, the second metatarsal head (30% and 32% of patients most common type of corn, appear as a firm, dry mass respectively), followed by the first metatarsal head with a polished surface and are found on the interpha- (21% and 23% of patients respectively). The role of langeal joints of the toes (Fig. 4.4A, B) and under the limb dominance in the formation of plantar keratotic metatarsal heads. Occasionally, hard corns may develop lesions is unclear. While Springett et al11 found no beneath the nail plate (referred to as subungual heloma) significant difference in prevalence according to pre- in response to pressure from footwear (Fig. 4.5). Hard ferred limb in 319 podiatry patients, Grouios12 found corns can become infiltrated with blood vessels and/ a higher prevalence of lesions on the dominant foot or nerve endings from the papillary dermis, and are in 115 athletes. then referred to as vascular corns (heloma vasculare) or neurovascular corns (heloma neurovasculare). If left untreated, longstanding hard corns may become sur- rounded by a meshwork of fibrous tissue (known as fibrous corns or heloma fascia). Soft corns (heloma molle) develop between the toes and have a character- istic rubbery texture due to the apposition of the toes preventing adequate evaporation (Fig. 4.6).14,15 Seed corns (heloma milliare) are small, superficial clusters of porokeratotic cells found embedded in plantar cal- luses, scattered around the heel or on non-weight- bearing areas of the plantar surface (Fig. 4.7).16 Seed corns are generally not painful. AETIOLOGY Pathogenesis The physiological mechanism responsible for the development of keratotic lesions is not fully under-

Classification and clinical presentation 63 ABCDE FGH I J Figure 4.2 The ten most common patterns of plantar callus formation. A. Second to fourth metatarsal heads (MHs) (23%). B. Second MH (18%). C. First and fifth MHs (14%). D. First MH (13%). E. Second and third MHs (10%). F. First to fifth MHs (8%). G. Third MH (8%). H. First to third MHs (8%). I. Fifth MH (7%). J. First and third MHs (7%). AB CD Figure 4.3 Common distribution patterns for hard corns (A, B), soft corns (C) and seed corns (D). stood. In response to repetitive friction or pressure, tissues by dispersing the applied forces over a larger normal healthy skin undergoes accelerated keratinisa- area and volume of skin. Histological studies have tion and a decreased rate of desquamation, resulting revealed several notable changes in calloused skin, in an increase in the thickness of the stratum including an increase in the thickness of the stratum corneum.17 This process, sometimes referred to as corneum and stratum granulosum, a decrease in physiological hyperkeratosis, is considered to be a pro- density (but increase in thickness) of keratinocytes tective mechanism that prevents damage to deeper and an exaggerated pattern of rete pegs.18 These

64 KERATOTIC DISORDERS Figure 4.5 Subungual heloma. (Courtesy of Amanda A Taylor, Charles Sturt University.) B Figure 4.6 Interdigital soft corn (heloma molle), located Figure 4.4 Hard corns (heloma dura). A. Dorsal surface between the fourth and fifth toes. (Courtesy of Lloyd of the fourth proximal interphalangeal joint. B. Apex of Reed, Queensland University of Technology.) the third toe. (Courtesy of Lloyd Reed, Queensland University of Technology.) sive, resulting in a large build-up of dense, keratinised tissue. Further pressure applied to the lesion leads to changes are thought to represent an increased rate a cycle of skin injury, repair and adaptation, and the of epidermal cellular production and an associated compression of nerve endings in the papillary dermis decrease in the differentiation of keratinocytes as they caused by the lesion leads to pain (Fig. 4.8). If left progress to the upper layers of the skin. Corns have untreated, keratotic lesions can cause considerable a similar structure; however, the underlying dermis damage to deeper layers of the skin, particularly exhibits significant degeneration of collagen fibres in people with diabetes. Indeed, the presence of and an increased number of fibroblasts.19–21 plantar keratotic lesions is a strong predictor of foot ulceration in people with diabetic peripheral For reasons that are still unknown, in some indi- neuropathy.9 viduals the process of hyperkeratosis becomes exces-

Classification and clinical presentation 65 Compression and shear forces applied to skin Dermal inflammatory response – vasodilatation of vascular bed Increased dermal fibroblast activity Figure 4.7 Close-up view of seed corns (heloma milliare) Increased epidermal basal cell mitosis on the plantar aspect of the foot. (Courtesy of Lloyd – decreased differentiation of cells Reed, Queensland University of Technology.) Crowding of cells at dermal-epidermal junction Four plantar pressure measurement studies have – exaggerated pattern of rete pegs provided evidence that plantar calluses tend to develop in regions of elevated pressure. Robertson22 compared Hypertrophy of stratum corneum 60 people with painful calluses under the first meta- tarsophalangeal joint to a matched control group and Pressure on nerves in papillary dermis found that the peak plantar pressure was significantly higher under all metatarsophalangeal joints (includ- Pain ing a 116% increase under the first metatarsophalan- geal joint) in the group with callus. A similar result Figure 4.8 Pathogenesis of keratotic lesions. was reported by Potter & Potter,23 who assessed pres- sures at a range of sites in people with and without O’Halloran28 revealed that, while the cholesterol calluses and reported an average increase in pressure content of seed corns was higher than that of normal of 25% at sites with an overlying callus. In a study of skin, it was no different to that of hard corns, indicat- 23 people with diabetes, Pataky et al24 observed that ing that the cholesterol content of skin is a marker of those with calluses under the third metatarsophalan- keratinocyte proliferation. Vitamin deficiency, genetic geal joints exhibited 10% higher pressures than those predisposition to dry skin and fungal infection have without. Finally, the largest study so far conducted also been implicated.29,30 (involving 292 people aged 62–96 years of age) reported that peak plantar pressures were between 9% Risk factors and 12% higher in callused regions of the forefoot, with the exception of the first metatarsophalangeal No prospective studies have been undertaken to joint and the lesser toes.25 Although the magnitude determine the risk factors for the development of of pressure differences reported in these studies varies keratotic lesions, so our knowledge is limited to case- considerably, there does appear to be a relationship control studies and clinical observations. Posited risk between elevated pressures and calluses, which is factors for keratotic lesion formation are summarised further supported by studies reporting a reduction in pressure after the lesions are removed with a scalpel.24,26,27 The pathogenesis of seed corns has received little attention in the literature. Earlier reports suggested that these lesions were crystalline deposits of pure cholesterol; however, a chromatographic analysis by

66 KERATOTIC DISORDERS Table 4.2 Posited risk factors for the calluses in diabetic and non-diabetic older people is development of keratotic lesions similar;41,42 however, Woodburn et al43 have shown that people with rheumatoid arthritis do have a higher Intrinsic Extrinsic prevalence of plantar forefoot calluses compared to age-matched controls. The likely mechanism for the Increased age Footwear speculated increased prevalence associated with these Female sex Narrow toe box conditions is the associated increase in foot deformity Obesity Elevated heel and diminished resilience of the skin. Comorbidities Textured insoles (‘health Diabetes mellitus Corns and calluses are frequently associated with Rheumatoid arthritis sandals keratosis’) foot deformities such as hallux valgus, hallux limitus Cerebrovascular accident Occupational/lifestyle and lesser toe deformities, because of changes in Systemic sclerosis plantar pressure distribution when walking and the Foot deformity factors inherent difficulty in obtaining footwear to accom- Hallux valgus Prolonged weightbearing modate bony prominences.44,45 In a sample of 135 Hallus limitus/rigidus Prolonged bed rest older people, Menz et al8 have shown that plantar Lesser toe deformity Prayer posture (‘Mecca calluses were more prevalent in those with hallux Pes planus and pes cavus valgus, whereas corns on the toes were more prevalent Foot surgery complications foot’) in those with lesser digital deformity. The relationship Reduced range of motion between foot posture, range of motion and plantar lesions is not as clear, although Woodburn et al43 in Table 4.2 and can be divided into intrinsic factors reported that people with rheumatoid arthritis and a (such as age, sex, co-morbidities and foot deformities) valgus heel had a higher prevalence of plantar calluses and extrinsic risk factors (such as ill-fitting footwear on the medial forefoot than those with a neutral heel, and occupational or lifestyle factors). Each of these and Bevans & Bowker33 have shown that a pronated factors is discussed in detail in the following section. foot type, limited first metatarsophalangeal joint motion and limited ankle joint range of motion are The community-based epidemiological studies associated with the presence of calluses in people with outlined in Chapter 1 indicate that the prevalence of diabetes. Finally, foot surgery is a well-recognised corns and calluses increases with age5,31,32 and female cause of plantar lesions (referred to as transfer lesions), sex.3,32 The increased prevalence with advancing age which frequently develop in response to the altered is most probably related to age-related changes in skin weightbearing patterns following procedures that structure and function (particularly the decreased involve metatarsal shortening.46,47 function of sweat glands and thinning of the dermis), in addition to the associated increase in the prevalence Perhaps the most common risk factor for keratotic of foot deformities, while the association with female lesions in older people is ill-fitting footwear and the sex may be partly attributable to footwear. Several wearing of shoes with an elevated heel. It has long authors have speculated that plantar calluses may be been recognised that many older people wear shoes associated with increased body mass index12,33,34 due that are too narrow or too short, leading to compres- to the subsequent increase in weightbearing pres- sion of the toes in the front of the shoe and subse- sures.35,36 In particular, heel calluses (and associated quent development of lesions.48,49 In addition, wearing fissuring) appear to be highly prevalent in obese older shoes with an elevated heel has been shown to mark- women who wear shoes without an enclosed heel edly increase weightbearing pressures on the forefoot, counter. a factor that is likely to predispose to the development of plantar lesions.50–53 These associations were recently Keratotic lesions are common in people with sys- confirmed by Menz & Morris,54 who took tracings of temic diseases such as diabetes,37 rheumatoid arthri- the feet and shoes of 176 older people and found that tis,38 stroke39 and systemic sclerosis;40 however, more than three-quarters of the sample wore shoes whether the prevalence of calluses and corns is greater narrower than their feet. An assessment of foot prob- in people with these conditions compared to the lems revealed that wearing shoes substantially nar- general older population remains unclear. Two case- rower than the foot was associated with corns on the control studies have shown that the prevalence of toes, hallux valgus deformity and foot pain, whereas wearing shoes shorter than the foot was associated

Assessment and diagnosis 67 with lesser toe deformity. Wearing shoes with heel A elevation greater than 25 mm was associated with hallux valgus and plantar calluses in women. A less common potential footwear-related risk factor for plantar calluses is the use of sandals with multiple raised projections designed to stimulate the soles when walking. Yoshii et al55 reported 13 cases of plantar calluses in otherwise healthy people that had developed after wearing such shoes, which they labelled ‘health sandals keratosis’. In each case, the lesions resolved after patients stopped wearing the sandals. Occupational and lifestyle factors, such as extended periods of weightbearing and performing repetitive activities involving the foot, are also likely to play a role in the development of keratotic lesions. Several examples have been described in the literature, such as the formation of dorsolateral foot lesions in people who sit cross-legged for long periods for either work56 or prayer (the so-called ‘Mecca foot’).57,58 Conversely, extended periods of bed rest may also lead to the development of calluses on the posterior heel and malleoli, which may progress to pressure ulcers if pressure redistribution is inadequate.59 Less common causes of keratotic lesions B Figure 4.9 Plantar (A) and palmar (B) lesions associated The preceding discussion has focused on mechani- with the punctuate form of palmoplantar keratoderma. cally-induced hyperkeratosis, which is the most (Courtesy of Lesley Newcombe, La Trobe University.) common cause of corns and calluses in older people. However, there are many, less commonly-encoun- lesions on the palms. Calluses and corns can some- tered conditions which may manifest as keratotic times be confused with verrucae (warts), and indeed lesions on the foot, such as palmoplantar keratoderma longstanding warts may develop a thick covering layer (Fig. 4.9).60,61 A brief summary of these conditions is of hyperkeratosis. However, verrucae do not generally provided in Table 4.3. form on weightbearing areas, are more acutely painful when lateral pressure is applied to the lesion, and will ASSESSMENT AND DIAGNOSIS exhibit characteristic pinpoint bleeding when debrided because of the presence of thrombosed blood vessels The diagnosis of keratotic lesions is relatively straight- within the lesion itself.13,45,62,63 forward, as their appearance is generally stereotypical and there are few common differential diagnoses to consider. Mechanically induced lesions can be differ- entiated from hyperkeratosis caused by inherited der- matological diseases or chemical toxicity by taking a thorough medical history and from clinical observa- tions of lesion distribution patterns. Mechanically induced lesions will appear on weightbearing areas or bony prominences subjected to pressure from foot- wear, whereas keratotic lesions due to other causes are generally more widespread and associated with similar

68 KERATOTIC DISORDERS Table 4.3 Less common causes of keratotic lesions in older people Classification Condition Aetiology Appearance Treatment Inherited Palmoplantar Autosomal dominant Diffuse thick hyperkeratosis of Emollients, disorders keratoderma palms and soles, often keratolytics, Autosomal recessive associated with fissuring debridement Disorders Mal de Meleda associated Autosomal dominant As above, in addition to Emollients, with Keratoderma discrete keratoses on keratolytics, malignancy punctata Autosomal dominant extensor surfaces debridement Other Keratosis follicularis Autosomal dominant Multiple punctuate Emollients, (Darier’s disease) hyperkeratotic lesions on keratolytics, Precedes oesophageal palms and soles debridement Palmoplantar carcinoma keratoderma Small scaly or waxy papules Emollients, Associated with upper most commonly found on keratolytics, Diffuse respiratory and scalp, chest and back. corticosteroids palmoplantar gastrointestinal Appear as punctuate keratosis (Howel- carcinoma keratoses when the palms Emollients, Evans’s and soles are affected keratolytics, syndrome) Group of disorders. debridement May be inherited or Diffuse thick hyperkeratosis of Acrokeratosis acquired palms and soles, often Emollients, paraneoplastica associated with fissuring keratolytics, (Bazex’s Excessive or debridement syndrome) prolonged sunlight Diffuse hyperkeratosis of palms exposure and soles Emollients, Ichthyosis keratolytics, Exposure to arsenical Diffuse hyperkeratosis of palms debridement Actinic keratosis compounds in and soles, nail hypertrophy (‘senile medications, Emollients, keratosis’) insecticides or Characteristic dry ‘fish-scale’ keratolytics, drinking water lesions with fissuring on retinoic acid, Arsenical keratosis elbows, knees, forehead, corticosteroids Cause unknown. arms, thighs, palms and Keratoderma Occurs in soles Cryotherapy, climacterium postmenopausal curettage, women and is Well-defined, raised red electrotherapy, associated with papules or plaques with topical obesity and rough surface of adherent 5-flurouracil hypertension scales, most commonly located on exposed areas of Emollients, skin keratolytics, debridement Discrete, yellow, punctuate round lesions on palms and Emollients, soles keratolytics, debridement, Marked thickening of palms corticosteroids and soles with deep fissures

Treatment 69 Once differential diagnoses are ruled out, the next Figure 4.10 Scalpel debridement and enucleation of a step is to determine the underlying cause of the lesion. heloma durum. (Courtesy of Lloyd Reed, Queensland This will involve careful observation and palpation, University of Technology.) noting the presence of hallux valgus, hallux limitus, lesser toe deformities, relative lengths of the metatar- sals and overall posture of the foot (pronated, neutral or supinated). Joint range of motion assessments are also useful, as restricted motion of metatarsophalan- geal joints may result in the generation of excessive plantar pressures when walking.64,65 Footwear should be carefully examined, with particular emphasis placed on the width and depth of the toe-box, the height of the heel and the presence of irregularities in the inner lining of the shoe (such as prominent stitching) that may be pressing on the foot. In-shoe devices such as insoles, foot orthoses, ankle–foot orthoses or other forms of bracing should also be evaluated. The plantar pressure systems outlined in Chapter 3 may be useful to locate and quantify regions of high pressure under the foot but they are rarely required to confirm a diagnosis. Similarly, the use of radiographs to visualise bony prominences, or histological analysis of the lesion, is generally not necessary. TREATMENT AB Figure 4.11 Plantar heloma durum before (A) and after CONSERVATIVE TREATMENTS (B) scalpel debridement and enucleation. (Courtesy of Matthew Dilnot, Melbourne Foot Clinic.) Lesion debridement and, unless the underlying cause is addressed, most The first step in the treatment of keratotic lesions is lesions will recur after a number of days or weeks.69,70 sharp debridement or enucleation with a scalpel (Figs The optimum frequency of repeat appointments for 4.10, 4.11). This procedure requires a considerable ongoing management of keratotic lesions is unknown, level of manual dexterity, particularly in the case of as the rate of recurrence of keratotic lesions is highly deep-seated neurovascular corns or interdigital soft variable. Potter & Potter71 have recently shown that corns. Debridement and enucleation provide immedi- callus regrowth over the first 2 weeks following ate symptomatic relief,66 increase the bearable pres- debridement varies considerably, even within indi- sure threshold of the foot67 and reduce weightbearing viduals. Three distinct patterns were observed: slow- pressures by up to 30%.24,26,27 There is also some pre- growing calluses, which only grew to 30% of their liminary evidence that debridement of lesions may original size during the 2-week period; medium- improve mobility in older people. Balanowski & growing calluses, which grew to 30–60% of their Flynn68 assessed functional ability (including ascend- original size; and fast-growing calluses, which grew to ing and descending stairs, an alternate stepping test and walking speed) and balance in people aged over 65 before and after scalpel debridement of painful plantar keratoses. After debridement, there was a sig- nificant reduction in pain and significant improve- ments in all three functional tests, which were maintained at a follow-up appointment 1 week later. Debridement and enucleation of keratotic lesions, however, provides only short-term relief of symptoms

70 KERATOTIC DISORDERS 60–70% of their original size. The surface area and thickness of the original lesion did not appear to influ- ence the rate of regrowth; however, it was reported that lesions over the fifth metatarsal head were more likely to be fast-growing and that lesions under the second metatarsal head were more likely to be slow- growing. The underlying physiological mechanisms for these differences remain unclear but are likely to be related to level of activity, footwear characteristics and level of skin hydration. Topical treatments Figure 4.12 Heel callus with associated fissuring. (Courtesy of Lloyd Reed, Queensland University of A wide range of topical treatments have been pro- Technology.) posed to both chemically debride keratotic lesions and inhibit their regrowth. In 1782, Laforest pre- reported that 21% of corns and 14% of calluses had scribed a concoction consisting of pork fat and ‘the resolved after 5 weeks of hydrocolloid treatment.78 A mousse that forms around boats’72 and, since that subsequent randomised trial comparing three adhe- time, a similarly colourful array of ointments, tinc- sive dressings (compressed felt, polymer gel and a tures and poultices have been recommended for kera- hydrocolloid) for the treatment of symptomatic totic lesions.73 Contemporary topical agents include corns found that, while all treatments were effective salicylic acid,74–76 silver nitrate,77 silicone77 and hydro- in reducing pain and the size of the lesion, the hydro- colloid wound dressings.78 Although anecdotal reports colloid was reported by patients to be easier to use, and several short-term, uncontrolled studies suggest easier to keep in place and more aesthetically pleas- that these techniques may be effective,74,77,78 very few ing.72 However, whether this benefit is significant controlled trials have been undertaken. enough to justify the extra cost of the dressing is arguable. Salicylic acid, first described as a treatment for kera- totic lesions in ancient Greece,79 is believed to lower Heel calluses, which often present with associated the pH of the stratum corneum, thereby leading to skin dryness and fissuring (Fig. 4.12), can be difficult swelling, maceration and eventual desquamation of to treat, particularly in older people who are over- the lesion. Lang et al80 have shown that ‘corn plasters’ weight and wear shoes without an enclosed heel containing 40% w/w salicylic acid are more effective counter. Following debridement of the overlying than non-medicated placebo pads, producing com- callus and the edges of the fissures, topical application plete enucleation of 62% of digital hard corns over a of salicylic acid or emollient creams may be effective,82 21-day period. Subsequent comparison studies of dif- in addition to the firm application of an adhesive ferent types of corn plaster (i.e. different strengths and bandage to limit lateral expansion of the heel pad delivery systems) have reported similar rates of lesion when weightbearing. The application of cyanoacrylate resolution; however, the adverse effect of excessive adhesives to seal deep heel fissures has also been maceration of surrounding tissue appears to be more reported to be effective, producing wound closure likely in stronger preparations incorporating a waxy strength equivalent to suturing.83 matrix rather than an adhesive matrix.75,76 The use of salicylic acid also needs to be very carefully considered Injection therapy in people with diabetes, as several cases of foot ulcer- ation and infection have been reported following its In addition to topical applications, a range of prepara- use.81 tions for intralesional or sublesional injection have Hydrocolloid dressings, most commonly used in the management of open wounds, have recently been evaluated as a potential treatment for keratotic lesions because of their effect on skin hydration. An uncon- trolled study of 43 people with corns and calluses

Treatment 71 been reported, including sodium chloride, alcohol discoloration and migration of the silicone from the and liquid silicone.84–86 Dockery & Nilson85 have injection site have been reported in a small number reported clinical success in resolving chronic plantar of cases.93 keratotic lesions using weekly 0.5–1.0 ml intralesional injection of a 4% sclerosing solution consisting of 2 ml Orthotic therapy absolute ethyl alcohol with 48 ml of 2% lidocaine with adrenaline (epinephrine) 1 : 100 000. No controlled Redistribution or reduction of excessive foot pres- trials have been undertaken to adequately assess the sures has the potential to provide longer-term relief efficacy of this approach, and the mechanism of action of symptoms associated with keratotic lesions and, in is also unclear. It has been suggested that the injection some cases, complete resolution of the lesion may be acts as an ‘internal pad’, thus spreading weightbearing possible. Simple cushioning insoles placed inside the forces over a larger area; however, the duration of this shoe may assist in reducing the overall pressure under effect is unknown. the foot; however, individually customised pressure redistribution insoles are likely to be more effective. Similar anecdotal reports regarding the efficacy Figure 4.13 shows some of the more commonly used of liquid silicone injections have been reported by padding designs for offloading plantar keratotic Balkin;87–90 however, only two controlled trials have lesions. Several plantar pressure studies have con- so far been undertaken. Tollafield et al86 compared firmed that this approach is effective in redistributing the efficacy of liquid silicone and saline injections in pressures beneath the metatarsal heads.94–101 Similarly, 31 people with plantar lesions and found no differ- the application of small pads beneath the proximal ence between the groups with regard to pain, fre- interphalangeal joints has been shown to significantly quency of follow-up treatments or appearance of the reduce pressure borne by the apices of the toes.102,103 lesions. More recently, a randomised, placebo- In addition to these simple insole designs, orthoses controlled trial conducted in people with diabetic moulded to the foot from more rigid materials such peripheral neuropathy found that six injections of as polypropylene have also been shown to redistribute 0.2 ml liquid silicone were more effective in increas- pressures to the arch of the foot, thereby reducing ing plantar soft tissue thickness and reducing plantar forefoot pressures.104,105 pressure than a placebo (saline); however, there was no difference in the appearance of the calluses.91 A Despite the significant pressure reduction achieved follow-up paper by these authors reported that, after with insoles and foot orthoses, only three studies have 2 years, the increase in soft tissue thickness was largely demonstrated that this approach is effective in the maintained, although the treatment had lost some of management of calluses. Colagiuri et al106 randomly its pressure-reducing properties.92 Although no serious allocated 20 people with diabetes to receive either complications were reported in these studies, skin conventional debridement of their plantar lesions or ABCDEF Figure 4.13 Orthotic designs used to redistribute pressure away from keratotic lesions. A. Plantar metatarsal pad. B. Plantar cover. C. ‘U-ed’ plantar cover. D. Winged plantar cover. E. Arch pad. F. Toe prop.

72 KERATOTIC DISORDERS custom orthoses manufactured from a rigid plastic commencing this intervention, it also needs to be material. After 12 months, the orthotic group exhib- considered that the end result may not always be ited greater reductions in callus severity, with 16 out aesthetically pleasing and that the resilience and lon- of 22 calluses in the orthotic group demonstrating gevity of the shoe may be diminished in the process. significant improvement. More recently, Caselli et Footwear modifications are discussed in more detail al107 compared debridement alone to debridement in in Chapter 12. conjunction with either urethane or silicon gel insoles. After 4 weeks, a significant improvement in symptoms SURGICAL TREATMENT was observed in both insole groups, indicating that the use of insole therapy is more effective than Surgical intervention for keratotic lesions is generally debridement alone. Finally, Timson & Spooner70 ran- considered for older people with painful, chronic domly allocated 25 people with painful calluses to lesions that have failed to respond to conservative receive either debridement or insoles manufactured treatment, or as an option for older people who find from 4 mm medium-density ethyl vinyl acetate with ongoing maintenance visits inconvenient. Two broad apertures placed at the site of the lesion. Both groups categories are recognised – electrosurgery, a relatively demonstrated significant reductions in pain immedi- atraumatic procedure that involves removing the ately following treatment; however, the reduction was lesion using high-frequency current, and orthopaedic greater in the debridement group. At 6-week follow- surgery, which is far more invasive, has a greater up, pain relief was maintained in the insole group; potential for complications and requires lengthier however, pain levels in the debridement group had periods of rehabilitation. Both approaches should be returned to their pretreatment level. carefully considered in the context of their potential costs and benefits. Alleviating pressures from keratotic lesions on the dorsum of the toes or between the toes is somewhat Electrosurgery more difficult, as it is more dependent on the ade- quacy of the footwear. Several approaches have been Electrosurgery has been used for several decades in a used with anecdotal evidence of clinical success, range of dermatological applications, most commonly including simple lamb’s wool, foam toe spacers and in the treatment of small skin lesions such as verrucae, silicone gel sleeves, many of which are now available skin tags and naevi. The procedure employs high- as over-the-counter products from pharmacies and frequency alternating current, which produces heat supermarkets.108 Devices customised to the shape of within cells, leading to modifications to the protein the individual’s foot can also be manufactured from content, evaporation of cellular fluids and the even- silicone elastomer materials (Ch. 11). tual destruction of the lesion and its separation from surrounding normal skin at the level of the dermal– Footwear modification epidermal junction.109,110 Two different approaches are used depending on the depth of the lesion: fulgu- If it is evident from clinical observations that the ration, in which the electrode is held away from the underlying cause of the keratotic lesion is related to skin to produce sparking at the skin surface, or elec- ill-fitting footwear, it is necessary to advise the older trodesiccation, in which the electrode is placed in person to consider purchasing a new pair of shoes contact with the skin to penetrate more deeply. Local with more adequate room in the toe-box. In some anaesthesia is generally required prior to administra- situations, however, this may not be possible for tion and, following treatment, sterile wound dressings financial reasons or because of reluctance on the part in conjunction with redistributive padding should be of the older person to wear wider-fitting shoes. In applied. these circumstances, it is worth considering modify- ing the existing footwear to accommodate the lesion. No controlled trials have evaluated the efficacy of This can be achieved using shoe-stretching devices, electrosurgery in the treatment of keratotic lesions; cutting out sections of the upper, or balloon patching. however, a number of case series studies report favour- Medical-grade footwear manufacturers or pedorthists able results for longstanding lesions. A case series of will often need to be consulted to undertake these 50 patients with vascular and neurovascular corns modifications, as they require considerable manual reported by Smith & Morrison110 indicated that 45% skill and the appropriate tools and materials. Before

Treatment 73 of lesions completely resolved after a period of 4–6 A weeks and a further 50% showed sufficient improve- B ment to enable ongoing management with scalpel C debridement. A follow-up study 4 years later reported improved rates of lesion resolution (71–90%), which the authors attributed to improvements in postopera- tive management.111 More recently, Whinfield & Forster112 reported a 73% reduction in pain associated with chronic hard corns 6 weeks after electrodesicca- tion and, at 12 months, pain levels were 58% of their pretreatment values. Although further studies are required to substantiate these findings, it would appear that electrosurgery may be useful for the treatment of chronic painful lesions in older people who have not responded to conservative treatments or who are con- sidered not suitable for orthopaedic surgery. Orthopaedic surgery Figure 4.14 Weil osteotomy. A. Osteotomy made parallel to weightbearing surface. B. Plantar fragment translated Surgical treatment for plantar lesions was first proximally. C. Resultant overhang of bone removed and described by Meisenbach in 1916.113 Since then, there osteotomy fixed with cortical screw. have been a plethora of surgical approaches and modi- fications described in the literature, involving the cases.115,118,120–122 The most commonly reported com- removal of entire metatarsals, total or partial excision plication associated with the procedure is floating toes of metatarsal heads and a variety of approaches for (15–36% of cases),117,118,120,122 although transfer lesions shortening or dorsiflexing metatarsals.114 It is difficult are also relatively common (5–20% of cases).117,118,121,122 to evaluate the relative success of these approaches, as Although few direct comparisons of success rates few direct comparisons have been undertaken and in according to age have been undertaken, Winson et many studies the duration of follow-up is insufficient al115 have observed that complications are more likely to adequately assess the rate of complications. Never- in people aged over 65 years. theless, it is clear that lesion recurrence is relatively common, as are complications such as the develop- A number of authors have suggested that the Weil ment of new lesions at previously lesion-free sites osteotomy is most appropriate when the affected (transfer lesions), reduced toe function and delayed or metatarsal is excessively long, and that complications non-union of the osteotomy site. These complications arise when the procedure is administered to normal appear to be more likely to occur when the surgical length metatarsals.123,124 In cases where the objective procedure involves multiple osteotomies.115 of the surgery is to elevate the metatarsal without shortening it, the Schwartz osteotomy125 has been Currently, the most commonly performed proce- recommended. This procedure involves removing a dure for the surgical management of plantar lesions is wedge-shaped piece of bone from the anterior the Weil osteotomy, attributed to the American podi- aspect of the metatarsal head, leaving a plantar hinge atrist Lowell Scott Weil by Barouk.116 The aim of the of bone that is then dorsiflexed and fixed by a screw procedure is to shorten the metatarsal, and it involves (Fig. 4.15). A recent retrospective review of 25 a 30° oblique osteotomy through the metatarsal head and proximal displacement of the distal fragment, followed by screw fixation and excision of the remain- ing dorsal overhang (Fig. 4.14). The plantar lesion is also excised to the level of the dermis. Patient satisfac- tion with this procedure has been reported to range between 47% and 88% of cases,115,117–120 with com- plete resolution of the lesion reported in 39–78% of

74 KERATOTIC DISORDERS A patients reported that, while only 41% demonstrated complete resolution of their plantar lesion, there was a high level of patient satisfaction and a reduc- tion in the number of required podiatry visits postoperatively.124 Surgical procedures for keratotic lesions on the toes are selected according to the specific associated deformity (hammer toe, claw toe, mallet toe, etc.) and B the range of motion available at the metatarsophalan- geal and interphalangeal joints.44,126 These procedures are described in Chapter 8. C SUMMARY Figure 4.15 Schwartz osteotomy. A. The first osteotomy Keratotic lesions are among the most common foot is made parallel to the weightbearing surface and the complaints in older people, the management of which second on a slightly more acute angle, leaving a hinge accounts for the vast majority of a podiatrist’s work- of cortical bone intact. B. Wedge of bone removed. load. Although often considered a minor complaint, C. Head of metatarsal moved dorsally on cortical hinge longstanding lesions can be debilitating and severely and osteotomy fixed with vertical screw. impact on an older person’s quality of life. In most cases, keratotic lesions can be successfully managed with conservative interventions such as debridement, orthoses and footwear modifications. Surgery may be indicated for cases that fail to respond to conservative approaches; however, the risk of complications needs to be carefully considered. References 7. Benvenuti F, Ferrucci L, Guralnik JM et al. Foot pain and disability in older persons: an epidemio- 1. Black JR, Hale WE. Prevalence of foot complaints logic survey. Journal of the American Geriatrics in the elderly. Journal of the American Podiatric Society 1995; 43: 479–484. Medical Association 1987; 77: 308–311. 8. Menz HB, Lord SR. Foot pain impairs balance and 2. Gould N, Schneider W, Ashikaga T. Epidemiologi- functional ability in community-dwelling older cal survey of foot problems in the continental United people. Journal of the American Podiatric Medical States 1978–1979. Foot and Ankle 1980; 1: 8–10. Association 2001; 91: 222–229. 3. Dunn JE, Link CL, Felson DT et al. Prevalence of 9. Murray HJ, Young MJ, Hollis S et al. The associa- foot and ankle conditions in a multiethnic commu- tion between callus formation, high pressures and nity sample of older adults. American Journal of neuropathy in diabetic foot ulceration. Diabetic Epidemiology 2004; 159: 491–498. Medicine 1996; 13: 979–982. 4. Elton PJ, Sanderson SP. A chiropodial survey of 10. Merriman L, Griffiths C, Tollafield D. Plantar elderly persons over 65 years in the community. lesion patterns. Chiropodist 1987; 42: 145– Public Health 1986; 100: 219–232. 148. 5. Brodie BS, Rees CL, Robins DJ et al. Wessex Feet: 11. Springett KP, Whiting MF, Marriott C. Epidemiol- a regional foot health survey. Vol. I: The survey. ogy of plantar forefoot corns and calluses, and the Chiropodist 1988; 43: 152–165. influence of the dominant side. The Foot 2003; 13: 5–9. 6. Harvey I, Frankel S, Marks R et al. Foot morbidity and exposure to chiropody: population based study. British Medical Journal 1997; 315: 1054–1055.

References 75 12. Grouios G. Footedness as a potential factor that 28. O’Halloran NF. A biochemical investigation into contributes to the causation of corn and callus for- the cholesterol content of seed corns. Chiropodist mation in lower extremities of physically active indi- 1990; November: 215–218. viduals. The Foot 2005; 15: 154–162. 29. Trice EW. A new hypothesis on the etiology of 13. Singh D, Bentley G, Trevino SG. Callosities, corns, heloma milliare. Journal of the National Association and calluses. British Medical Journal 1996; 312: of Chiropodists 1955; 45: 28–29. 1403–1406. 30. McCarthy DJ. Helomata and tylomata. In: McCar- 14. Haboush EJ, Martin RV. Painful interdigital clavus thy DJ, Montgomery R, ed. Podiatric dermatology. (soft corn). Treatment by skin-plastic operation. Baltimore, MD: Williams & Wilkins; 1986: 53– Journal of Bone and Joint Surgery 1947; 29: 73. 756–757. 31. Greenberg L, Davis H. Foot problems in the US. 15. Gillett HGDP. Interdigital clavus. Clinical Ortho- The 1990 National Health Interview Survey. Journal paedics and Related Research 1979; 142: 103– of the American Podiatric Medical Association 1993; 109. 83: 475–483. 16. George DH. Management of hyperkeratotic lesions 32. Garrow AP, Silman AJ, Macfarlane GJ. The Cheshire in the elderly patient. Clinics in Podiatric Medicine Foot Pain and Disability Survey: a population survey and Surgery 1993; 10: 69–77. assessing prevalence and associations. Pain 2004; 110: 378–384. 17. Rubin L. Hyperkeratosis in response to mechanical irritation. Journal of Investigative Dermatology 33. Bevans JS, Bowker P. Foot structure and function: 1949; 13: 313–315. aetiological risk factors for callus formation in dia- betic and non-diabetic subjects. The Foot 1999; 9: 18. Thomas SE, Dykes PJ, Marks R. Plantar hyperkera- 120–127. tosis: a study of callosities and normal plantar skin. Journal of Investigative Dermatology 1985; 85: 34. Garcia-Hidalgo L, Orozco-Topete R, Gonzalez- 394–397. Barranco J et al. Dermatoses in 156 obese adults. Obesity Research 1999; 7: 299–302. 19. Bonavilla EJ. Histopathology of the heloma durum: some significant features and their implications. 35. Hills AP, Hennig EM, McDonald M et al. Plantar Journal of the American Podiatry Association 1968; pressure differences between obese and non-obese 58: 423–427. adults: a biomechanical analysis. International Journal of Obesity and Related Metabolic Disorders 20. Potter GK. Histopathology of clavi. Journal of the 2001; 25: 1674–1679. American Podiatry Association 1973; 63: 57–66. 36. Birtane M, Tuna H. The evaluation of plantar pres- 21. McCarthy DJ, Habowsky JE. Histochemistry and sure distribution in obese and non-obese adults. anthropometric analysis of heloma durum. Journal Clinical Biomechanics 2004; 19: 1055–1059. of the American Podiatry Association 1975; 65: 4–18. 37. Reed JF. An audit of lower extremity complications in octogenarian patients with diabetes mellitus. 22. Robertson K, Delbridge L. A comparative study of Lower Extremity Wounds 2004; 3: 161–164. forefoot pressures associated with corns and callus under the first metatarsal head. Chiropodist 1985; 38. Williams AE, Bowden AP. Meeting the challenge for 40: 101–107. foot health in rheumatic diseases. The Foot 2004; 14: 154–158. 23. Potter J, Potter M. Effect of callus removal on peak plantar pressures. The Foot 2000; 10: 23– 39. Jordan E, Lekkas C, Roscioli D et al. Podiatric prob- 26. lems on a stroke rehabilitation unit. Australian Journal on Ageing 1997; 16: 222–224. 24. Pataky Z, Golay A, Faravel L et al. The impact of callosities on the magnitude and duration of plantar 40. Sari-Kouzel H, Hutchinson C, Middleton A et al. pressure in patients with diabetes mellitus. Diabetes Foot problems in patients with systemic sclerosis. and Metabolism 2002; 28: 356–361. Rheumatology 2001; 40: 410–413. 25. Menz HB, Zammit GV, Munteanu SE. Plantar pres- 41. Evans SL, Nixon BP, Lee I et al. The prevalence and sures are higher under callused regions of the foot nature of podiatric problems in elderly diabetic in older people. Clinical and Experimental Derma- patients. Journal of the American Geriatrics Society tology 2007; 32: 375–380. 1991; 39: 241–245. 26. Young MJ, Cavanagh PR, Thomas G et al. The 42. Ronnemaa T, Liukkonen I, Knuts L-R et al. Preva- effect of callus removal on dynamic plantar foot pres- lence of foot problems and need for foot care in an sures in diabetic patients. Diabetic Medicine 1992; unselected diabetic population. Journal of British 9: 55–57. Podiatric Medicine 1993; 48: 185–190. 27. Pitei DL, Foster A, Edmonds M. The effect of 43. Woodburn J, Helliwell PS. Relation between heel regular callus removal on foot pressures. Journal of position and the distribution of forefoot plantar Foot and Ankle Surgery 1999; 38: 251–255. pressures and skin callosities in rheumatoid arthritis.

76 KERATOTIC DISORDERS Annals of the Rheumatic Diseases 1996; 55: 61. DeLauro TM. Keratotic lesions of the foot. Clinics 806–810. in Podiatric Medicine and Surgery 1996; 13: 73– 44. Coughlin MJ. Lesser-toe abnormalities. Journal of 84. Bone and Joint Surgery 2002; 84A: 1446–1469. 45. Mann RA, Mann JA. Keratotic disorders of the 62. Freeman D. Corns and calluses resulting from plantar skin. Journal of Bone and Joint Surgery mechanical hyperkeratosis. American Family Physi- 2003; 85A: 938–955. cian 2002; 65: 2277–2280. 46. Richardson EG. Complications after hallux valgus surgery. AAOS Instructional Course Lectures 1999; 63. Grouios G. Corns and calluses in athlete’s feet: a 48: 331–342. cause for concern. The Foot 2004; 14: 175–184. 47. Femino JE, Mueller K. Complications of lesser toe surgery. Clinical Orthopaedics and Related Research 64. Fernando DJS, Masson EA, Veves A et al. Relation- 2001; 391: 72–78. ship of limited joint mobility to abnormal foot pres- 48. Coughlin MJ, Thompson FM. The high price of sures and diabetic foot ulceration. Diabetes Care high-fashion footwear. AAOS Instructional Course 1991; 14: 8–11. Lectures 1995; 44: 371–377. 49. Frey C. Foot health and shoewear for women. Clini- 65. Menz HB, Morris ME. Clinical determinants of cal Orthopaedics and Related Research 2000; 372: plantar forces and pressures during walking in older 32–44. people. Gait and Posture 2006; 24: 229–236. 50. Snow RE, Williams KR, G B Holmes J. The effects of wearing high heeled shoes on pedal pressures in 66. Redmond A, Allen N, Vernon W. Effect of scalpel women. Foot and Ankle 1992; 13: 85–92. debridement on the pain associated with plantar 51. Corrigan JP, Moore DP, Stephens MM. Effect of hyperkeratosis. Journal of the American Podiatric heel height on forefoot loading. Foot and Ankle Medical Association 1999; 89: 515–519. 1993; 14: 148–152. 52. Nyska M, McCabe C, Linge K et al. Plantar forefoot 67. Prud’homme P, Curran M. A preliminary study of pressures during treadmill walking with high-heel the use of the algometer to investigate whether or and low-heel shoes. Foot and Ankle International not patients benefit when podiatrists enucleate corns. 1996; 17: 662–666. The Foot 1999; 9: 65–69. 53. Mandato MG, Nester E. The effects of increasing heel height on forefoot peak pressure. Journal of the 68. Balanowski KR, Flynn LM. Effect of painful kerato- American Podiatric Medical Association 1999; 89: ses debridement on foot pain, balance and function 75–80. in older adults. Gait and Posture 2005; 22: 302– 54. Menz HB, Morris ME. Footwear characteristics and 307. foot problems in older people. Gerontology 2005; 51: 346–351. 69. Woodburn J, Stableford Z, Helliwell P. Preliminary 55. Yoshii A, Ono T, Kayashima K et al. An unusual investigation of debridement of plantar callosities in mechanical hyperkeratosis of the soles – health rheumatoid arthritis. Rheumatology 2000; 39: sandals keratosis. Journal of Dermatology 1991; 18: 652–654. 291–294. 56. Wahlberg JE. Occupational hyperkeratosis in carpet 70. Timson S, Spooner SK. A comparison of the efficacy installers. American Journal of Industrial Medicine of scalpel debridement and insole therapy in reliev- 1985; 8: 351–353. ing the pain of plantar callus. British Journal of 57. Kahana M, Cohen M, Ronnen M et al. Prayer Podiatry 2005; 8: 53–59. nodules in Moslem men. Cutis 1986; 38: 281– 282. 71. Potter J, Potter M. Regrowth patterns of plantar 58. Roberts PJ, Katsimitas M, Wade RH. An interesting callus. The Foot 2000; 10: 144–148. behavioural injury: Mecca foot. Foot and Ankle Surgery 2001; 7: 49–50. 72. Springett K, Parsons S, Young M et al. The effect 59. Wong VK, Stotts NA. Physiology and prevention of and safety of three corn care products. British Journal heel ulcers: the state of science. Journal of Wound of Podiatry 2002; 5: 82–86. Ostomy and Continence Nursing 2003; 30: 191– 198. 73. LeRossignol JN. A pharmacopoeia for chiropodists. 60. Schiraldi FG. Common dermatologic manifestations 8th ed. London: Faber & Faber; 1970. in the older patient. Clinics in Podiatric Medicine and Surgery 1993; 10: 79–95. 74. Potter J. The use of salicylic acid in the treatment of dorsal corn and callus. British Journal of Podiatry 2000; 3: 51–55. 75. Nossiter H, Sanders J. A comparison of clinical effi- cacy of two delivery systems of salicylic acid in corn removal plasters. The Foot 1994; 4: 83–87. 76. Rinaldi F, Clemente F. The importance of the for- mulation of a plaster containing salicylic acid in treatment of corns. The Foot 1994; 4: 186–190. 77. Finch P. An evaluation of the treatment of plantar fibrous and hard corn using silicone plugging and silver nitrate. Chiropodist 1987; 42: 463–467. 78. Springett K, Deane M, Dancaster P. Treatment of corns, calluses and heel fissures with a hydrocolloid

References 77 dressing. Journal of British Podiatric Medicine 1997; 95. Hayda R, Tremaine M, Tremaine K et al. Effect of 52: 102–104. metatarsal pads and their positioning: a quantitative 79. Dagnall JC. History of salicilin and salicylic acid. assessment. Foot and Ankle International 1994; 15: Chiropodist 1958; 13: 118–119. 561–566. 80. Lang LMG, West SG, Day S et al. Salicylic acid in the treatment of corns. The Foot 1994; 4: 96. Chang A, Abu-Faraj Z, Harris G et al. Multistep 145–150. measurement of plantar pressure alterations using 81. Foster A, Edmonds ME, Das AK et al. Corn cures metatarsal pads. Foot and Ankle International 1994; can damage your feet: an important lesson for dia- 15: 654–660. betic patients. Diabetic Medicine 1989; 6: 818– 819. 97. Kato H, Takada T, Kawamura T et al. The reduction 82. Bikowski J. Hyperkeratosis of the heels: treatment and redistribution of plantar pressures using foot with salicylic acid in a novel delivery system. orthoses in diabetic patients. Diabetes Research and SKINmed 2004; November–December: 350–351. Clinical Practice 1996; 31: 115–118. 83. Hashimoto H. Superglue for the treatment of heel fissures. Journal of the American Podiatric Medical 98. Abu-Faraj Z, Harris G, Chang A et al. Evaluation of Association 1999; 89: 434–435. a rehabilitative pedorthic: plantar pressure alterations 84. Balkin SW. Silicone augmentation for plantar cal- with scaphoid pad application. IEEE Transactions in luses. Journal of the American Podiatry Association Rehabilitative Engineering 1996; 4: 328–336. 1976; 66: 148–154. 85. Dockery GL, Nilson RZ. Intralesional injections. 99. Hodge M, Bach T, Carter G. Orthotic management Clinics in Podiatric Medicine and Surgery 1986; 3: of plantar pressure and pain in rheumatoid arthritis. 473–485. Clinical Biomechanics 1999; 14: 567–575. 86. Tollafield DR, Holdcraft DJ, Singh R et al. Inject- able percutaneous polydimethicone in the treatment 100. Raspovic A, Newcombe L, Lloyd J et al. Effect of of pedal keratomas: a single blind randomized trial. customized insoles on vertical plantar pressures in Journal of Foot and Ankle Surgery 2001; 40: sites of previous neuropathic ulceration in the dia- 295–301. betic foot. The Foot 2000; 10: 133–138. 87. Balkin SW. Silicone injection for plantar keratoses. Preliminary report. Journal of the American Podiatry 101. Mueller MJ, Lott DJ, Hastings MK et al. Efficacy Association 1966; 56: 1–11. and mechanism of orthotic devices to unload meta- 88. Balkin SW. Plantar keratoses: treatment by injectable tarsal heads in people with diabetes and a history of liquid silicone. Report of an eight-year experience. plantar ulcers. Physical Therapy 2006; 86: 833– Clinical Orthopaedics and Related Research 1972; 842. 87: 235–247. 89. Balkin SW. Treatment of corns by injectable silicone. 102. Claisse PJ, Binning J, Potter J. Effect of orthotic Archives of Dermatology 1975; 111: 1143–1145. therapy on claw toe loading. Results of significance 90. Balkin SW. Injectable silicone and the foot: a 41-year testing at pressure sensor units. Journal of the Amer- clinical and histologic history. Dermatologic Surgery ican Podiatric Medical Association 2004; 94: 2005; 31: 1555–1559. 246–254. 91. VanSchie CHM, Whalley A, Vileikyte L et al. Effi- cacy of injected liquid silicone in the diabetic foot 103. Slater RA, Herschkowitz I, Ramot Y et al. Reduction to reduce risk factors for ulceration. Diabetes Care of digital plantar pressure by debridement and sili- 2000; 23: 634–638. cone orthosis. Diabetes Research and Clinical Prac- 92. VanSchie CH, Whalley A, Armstrong DG et al. The tice 2006; 74: 263–266. effect of silicone injections in the diabetic foot on peak plantar pressure and plantar tissue thickness: a 104. Redmond A, Lumb PS, Landorf K. Effect of cast 2-year follow-up. Archives of Physical Medicine and and noncast foot orthoses on plantar pressure and Rehabilitation 2002; 83: 919–923. force during normal gait. Journal of the American 93. Balkin SW, Kaplan L. Injectable silicone and the Podiatric Medical Association 2000; 90: 441–449. diabetic foot: a 25-year report. The Foot 1991; 2: 83–88. 105. Burns J, Crosbie J, Ouvrier R et al. Effective orthotic 94. Holmes G, Timmerman L. A quantitative assess- therapy for the painful cavus foot. Journal of the ment of the effect of metatarsal pads on plantar American Podiatric Medical Association 2006; 96: pressures. Foot and Ankle International 1990; 11: 205–211. 141–145. 106. Colagiuri S, Marsden LL, Naidu V et al. The use of orthotic devices to correct plantar callus in people with diabetes. Diabetes Research and Clinical Prac- tice 1995; 28: 29–34. 107. Caselli MA, Levitz SJ, Clark N et al. Comparison of Viscoped and Poron for painful submetatarsal hyper- keratotic lesions. Journal of the American Podiatric Medical Association 1997; 87: 6–10. 108. Bedinghaus JM, Niedfeldt MW. Over-the-counter foot remedies. American Family Physician 2001; 64: 791–796, 803–804.

78 KERATOTIC DISORDERS 109. Cresswell CC. Introduction to electrosurgery. radiological follow-up. The Foot 2005; 15: 202– Journal of British Podiatric Medicine 1992; January: 205. 11–14. 119. Hofstaetter SG, Hofstaetter JG, Petrousas JA et al. The Weil osteotomy: a seven year follow-up. Journal 110. Smith TJ, Morrison DC. A study into the use of of Bone and Joint Surgery 2005; 87B: 1507– electrosurgery for the treatment of vascular and neu- 1511. rovascular corns. Chiropodist 1986; 41: 164– 120. Beech I, Rees S, Tagoe M. A retrospective review of 170. the Weil metatarsal osteotomy for lesser metatarsal deformities: an intermediate follow-up analysis. 111. Smith TJ, Morrison DC. Further developments in Journal of Foot and Ankle Surgery 2005; 44: the use of electrosurgery for the treatment of heloma 358–364. durum. Chiropodist 1990; April: 67–68. 121. Vandeputte G, Dereymaeker G, Steenwerkx A et al. The Weil osteotomy of the lesser metatarsals: a clini- 112. Whinfield AL, Forster MSK. Effect of electro- cal and pedobarographic follow-up study. Foot and desiccation on pain intensity associated with Ankle International 2000; 21: 370–374. chronic heloma durum. The Foot 1997; 7: 224– 122. Gibbard KW, Kilmartin TE. The Weil osteotomy for 228. the treatment of painful plantar keratoses. The Foot 2003; 13: 199–203. 113. Meisenbach RO. Painful anterior arch of the foot: 123. Kilmartin TE. Distal lesser metatarsal osteotomies: a an operation for its relief by means of raising the review of surgical techniques designed to avoid non- arch. American Journal of Orthopaedic Surgery union and minimize transfer metatarsalgia. The Foot 1916; 14: 206. 1998; 8: 186–192. 124. Finney S, Kilmartin T, Flintham C. The modified 114. Hatcher RM, Goller WL, Weil LS. Intractable Schwartz procedure in the management of intracta- plantar keratoses. A review of surgical corrections. ble plantar keratoses: a retrospective review. The Journal of the American Podiatry Association 1978; Foot 2003; 13: 108–113. 68: 377–386. 125. Schwartz N, Williams JE, Marcinko DE. Double oblique lesser metatarsal osteotomy. Journal of the 115. Winson IG, Rawlinson J, Broughton NS. Treatment American Podiatric Medical Association 1983; 73: of metatarsalgia by sliding distal metatarsal osteot- 218–220. omy. Foot and Ankle 1988; 9: 2–6. 126. Coughlin MJ. Mallet toes, hammer toes, claw toes and corns. Causes and treatment of lesser-toe defor- 116. Barouk LS. Weil’s metatarsal osteotomy in the mities. Postgraduate Medicine 1984; 75: 191–198. treatment of metatarsalgia. Orthopade 1996; 25: 338–344. 117. O’Kane C, Kilmartin TE. The surgical management of central metatarsalgia. Foot and Ankle Interna- tional 2002; 23: 415–419. 118. Sharma DK, Roy N, Shenolikar A. Weil osteotomy of lesser metatarsals for metatarsalgia: a clinical and

Other skin disorders CHAPTER 5 CHAPTER CONTENTS Disorders of the skin are very common in older people.1 Surveys of clinical populations indicate that Eczema and dermatitis 80 the most common presenting complaints in people Xerotic eczema 80 aged over 65 years are eczema/dermatitis, fungal Venous stasis eczema 80 infections, pruritus, actinic keratosis, benign tumours Drug-induced eczema 81 and malignant tumours.2–7 Establishing the preva- lence of skin lesions of the foot, however, is difficult, Papulosquamous diseases 81 as few large-scale dermatology studies specify the Psoriasis 81 body part affected by the condition and foot-specific Lichen planus 82 studies tend to focus on keratotic lesions or orthopae- dic conditions. The most commonly reported skin Skin infections 83 83 condition in older people in the large-scale, foot-spe- Erysipelas and cellulitis cific studies is ‘dry skin’ (prevalence estimates ranging Pitted keratolysis 83 from 13% to 27%),8–10 followed by various classifica- Tinea pedis 83 tions of foot infections (2–47%).10–13 The most detailed data can be derived from the Achilles Foot Screening Tumours, cysts and lesions 85 Project, which involved clinical and mycological Benign lesions 86 examination of the feet of people attending derma- Premalignant and malignant lesions 92 tologists or primary care physicians in 16 countries.14 Although no doubt an overestimate because of re- Summary 95 sponse bias, the findings of this study indicate that References 95 between 60% and 90% of people aged over 65 years had evidence of foot disease, the most common con- dition being tinea pedis (29% of older people). The following chapter provides an overview of the most common skin conditions affecting the older foot, along with less common conditions with poten- tially serious ramifications (i.e. premalignant and malignant lesions). The reader should note, however, that the coverage in this chapter is by no means exhaustive, and it is therefore advisable to supplement this information with a general dermatology text or Dockery’s Cutaneous Disorders of the Lower Extrem- ity.15 It is also worth noting that while the treatment

80 OTHER SKIN DISORDERS of some of the more common skin conditions is well supported by evidence from randomised controlled trials, the management of more obscure lesions is largely informed by clinical experience. The findings of relevant systematic reviews conducted by the Cochrane Collaboration are provided where available; however, at the time of writing several of these (such as the treatment of psoriasis,16 cellulitis,17 actinic kera- toses,18 surgical treatment for malignant melanoma19 and non-melanoma skin cancers)20 were still under development. ECZEMA AND DERMATITIS Figure 5.1 Xerotic eczema. (Courtesy of Lesley Newcombe, La Trobe University.) The term ‘eczema’ refers to any form of non-infective inflammation of the skin and is often used inter- Figure 5.2 Venous stasis eczema affecting the medial changeably with the term ‘dermatitis’. Eczema can be ankle region. (Courtesy of Lesley Newcombe, La Trobe broadly classified as exogenous (i.e. caused by external University.) irritants) or endogenous (i.e. caused by internal physi- ological factors). However, because the aetiology of suggested that older people with severe forms of many forms of eczema is unknown, such a distinction the condition should consider purchasing a is not always possible, and indeed in some conditions humidifier.15,21,23 a combination of external irritants and internal factors is likely to be responsible. For the same reason, deter- VENOUS STASIS ECZEMA mining the prevalence of eczema in older people is very difficult, with reported prevalence rates ranging Venous stasis eczema (also referred to as stasis derma- between 35% and 59%.4–6 Excessively dry and scaly titis, varicose eczema or gravitational eczema) is skin, one of the most common complaints associated characterised by oedema, hyperaemia, pruritus, hae- with eczema affecting the foot, is reported by between mosiderosis and superficial scaling of skin in the lower 13% and 27% of those aged over 65 years.8–10 The tibial area, and is associated with chronic venous most common forms of eczema in older people are insufficiency24 (Fig. 5.2). The peak incidence of onset discussed below. is in the third to fourth decade, and women are three times more likely to develop the condition than XEROTIC ECZEMA men. The condition most commonly develops after a venous ulcer has healed, leaving the epidermis Also known as asteatotic dermatitis, eczema craquelé and chronic winter itch, this condition is characterised by erythematous dry scaling and fissuring of the skin, and is most commonly found on the anterolateral aspects of the legs in older people (Fig. 5.1). The lesions are often highly pruritic and continued scratch- ing exacerbates the condition. Xerotic eczema is thought to be caused by a reduction in epidermal lipids due to excessive use of soaps and detergents, frequent bathing in very hot water, excessive room heating and inadequate household humidity. The condition is particularly common in older people residing in aged care facilities.21 Treatment involves the application of emollient or corticosteroid creams and educating the older person or their carer about the use of moisturising soaps.21–23 It has also been

Papulosquamous diseases 81 atrophic and the underlying dermis sclerotic and Table 5.1 Common medications associated indurated. Treatment involves management of the with different presentations of drug eruptions underlying venous condition (e.g. limb elevation, the use of compression stockings and exercise) in addition Drug eruption Common causative medications to managing pruritus with topical corticosteroids25 and maintaining skin integrity with the application of Urticarial Aspirin emollient creams.26 reaction Penicillin DRUG-INDUCED ECZEMA Morbilliform Ampicillin eruption Gentamicin A wide range of medications may produce skin erup- Phenothiazines tions in older people and lead to the development Sulphonamides of eczema. However, because many older people take Thiazides multiple medications, it is often difficult to determine Quinidine the causative agent. Furthermore, while some medica- tions produce immediate skin reactions, others may Erythema Sulphonamides take months or even years to manifest. Broadly speak- nodosum Penicillin ing, six main types of drug reaction are observed: Halogens urticarial reactions, which manifest as a pruritic red wheals and are caused by an acute hypersensitivity Acroexfoliative Aspirin response, morbilliform eruptions, which create ery- dermatitis Codeine thematous macular and papular rashes, erythema mul- Iodine tiforme, an acute bullous reaction associated with Sulphonamides systemic symptoms such as fever and muscular pains, Phenytoin acroexfoliative dermatitis, which produces lichenifica- tion and superficial shedding of skin, exfoliative eryth- Exfoliative Allopurinol roderma, a serious condition characterised by severe erythroderma Cimetidine pruritic scaling and desquamation, and lichenoid der- Phenytoin matitis, characterised by multiple flat-topped papules.15 Iodine Because they are potentially life-threatening, it is Penicillin essential that a thorough evaluation be undertaken Sulphonamides when older people present with suspected drug erup- tions. Signs that may indicate severe reactions include Lichenoid Beta-blockers pronounced erythema, skin pain, necrosis, Nikolsky’s dermatitis Non-steroidal anti-inflammatory drugs sign (separation of the epidermis from the dermis with Thiazides mild lateral pressure), swelling of the tongue, high Quinidine fever, enlarged lymph nodes, shortness of breath and arthritic symptoms.27 Common medications associ- any part of the body but most commonly the ated with each of these presentations are shown in scalp, elbows and knees28 (Fig. 5.3). Foot and toenail Table 5.1. Treatment of these conditions requires the involvement is common, and up to 30% of people identification and, if possible, discontinuation of the with psoriasis will also develop arthropathy in the offending medication, along with topical therapy to distal joints, including the interphalangeal joints maintain skin integrity. of the toes.29,30 Psoriasis affects approximately 2% of the population and can begin at any age; however, PAPULOSQUAMOUS DISEASES the peak incidence occurs in the second and third decades.31,32 The cause of psoriasis is not well PSORIASIS understood; however, a positive family history is evident in 35% of patients and the condition appears Psoriasis is a chronic inflammatory skin condition to be triggered by a range of factors such as trauma, characterised by the formation of well demarcated infection, some medications, alcohol, smoking and erythematous plaques and superficial scales involving stress.33 Three main types of psoriasis have been recog- nised: chronic plaque psoriasis (also referred to as ordi-

82 OTHER SKIN DISORDERS AB Figure 5.5 Lichen planus. (With permission from Figure 5.3 Chronic plaque psoriasis affecting (A) the DermNet NZ, www.dermnetnz.org. Copyright © 2007 anterior aspect of the leg and (B) the dorsum of the Interactive Medical Media LLC, All rights reserved.) foot. (A, courtesy of Amanda Taylor, Charles Sturt University; B, courtesy of Felicity Prentice, La Trobe psoriatic lesions at sites of previous injury to the skin. University.) Toenail involvement is characterised by pitting of the nail plate, formation of subungual hyperkeratosis and, Figure 5.4 Pustular psoriasis affecting the medial arch in severe cases, onycholysis (separation of the nail of the foot. (Courtesy of Karl Landorf, La Trobe plate from the underlying nail bed).15,34 University.) First-line treatment of psoriasis involves the man- agement of lesions with topical emollients, corti- costeroids, tar-based preparations or salicylic acid.35 However, a recent systematic review indicated that these treatments provide only temporary relief and recurrence is common, often in a more severe form than the original presentation (the so-called ‘rebound effect’).36 For long-standing psoriasis, systemic treat- ments include photochemotherapy (exposure of the skin to ultraviolet A following oral administration of psoralen), oral retinoid (a vitamin A derivative, often used in conjunction with ultraviolet A) and metho- trexate (a folate antagonist with anti-inflammatory and immune-modulating effects).36 nary psoriasis or psoriasis vulgaris), which is the most LICHEN PLANUS common form, guttate psoriasis, in which several drop-like lesions form symmetrically on the trunk Lichen planus is an inflammatory condition character- following a streptococcal throat infection, and pustu- ised by the formation of sharply defined, flat, shiny, lar psoriasis, which is more common in older women polygonal, pruritic papules on the wrists, lumbar and is characterised by the development of erythema- region, scalp, tibial area and, less commonly, the foot tous, yellow to brown vesicles on the palms and arch (Fig. 5.5). The peak incidence of onset is between the of the foot (Fig. 5.4).15,34 Two key clinical features of ages of 30 and 60 years, and women are affected more chronic plaque psoriasis can greatly assist in establish- frequently than men.28 The aetiology is not fully ing a diagnosis: Auspitz’s sign, the appearance of pin- understood. The most common site of foot involve- point bleeding when the superficial scales are removed, ment is the plantar medial arch,37,38 where the lesions and the Koebner phenomenon, the appearance of may develop a more hyperkeratotic appearance than other regions and, in rare cases, may ulcerate.39 Nail

Skin infections 83 involvement may also occur, resulting in thinning of The bacteria gain access to the deeper tissues the nail plate, formation of subungual hyperkeratosis through open wounds, such as leg or foot ulcers, and fusion of the proximal nail fold to the nail bed.34 interdigital fissures and subungual lesions, or as the Spontaneous resolution occurs in most cases over result of surgery. Several case-control studies have a period of 6–18 months; however, relapses occur confirmed that the presence of chronic fungal infec- in 10–25% of cases.40 Treatment involves topical or tion affecting the interdigital spaces markedly increases oral corticosteroids, and antihistamines to manage the risk of cellulitis.47–49 Furthermore, foot surgery has pruritus. In severe cases, photochemotherapy may be been shown to be associated with higher postoperative considered. infection rates than procedures performed on other parts of the body.50,51 Death from cellulitis-related SKIN INFECTIONS septicaemia has also been reported in an 87-year-old woman with peripheral vascular disease following As stated in Chapter 2, ageing is associated with sig- non-surgical treatment for an ingrown toenail.52 nificant changes to the structure and function of the skin. Several of these changes, such as the reduction The key presenting features of cellulitis are swell- in the number of Langerhans cells41 and the reduction ing, erythema and pain in the affected limb, accom- in the number of capillary loops in the dermis,42 affect panied by high fever and lymph node enlargement. A the barrier function of the skin and reduce the efficacy clearly demarcated margin indicating the spread of the of the immune response.43 As a consequence, the risk bacteria is often visible (Fig. 5.6) and in severe cases of skin infection increases significantly with advancing there may be evidence of necrosis or gangrene. Admis- age. In the foot, this risk is further exacerbated by the sion to hospital is generally necessary, as untreated wearing of footwear and hosiery, which provides an cellulitis may lead to septicaemia. Treatment involves ideal warm and humid environment for growth of antibiotics, the selection of which is dependent on many types of bacteria and fungi. In the presence of determining the causative bacteria. In cases related to minor breaks in the skin, such as fissuring between leg ulcers, broad-spectrum antibiotics are generally the toes, superficial infections can quickly develop used as it is likely that multiple species of bacteria are into far more serious conditions that may be limb- involved.53 threatening or even life-threatening. The following section provides an overview of the most common PITTED KERATOLYSIS skin infections seen in older people. Nail infections are covered in Chapter 6. Pitted keratolysis is a condition caused by infection of the plantar stratum corneum by the Corynebacterium ERYSIPELAS AND CELLULITIS species of bacteria54 and, less commonly, Micrococcus sedentarius55 or Dermatophilus congolensis.56 The con- The term erysipelas refers to an acute infection of the dition frequently develops in barefoot populations, dermis, whereas cellulitis refers to an acute or chronic or in people whose occupation subjects them to infection of connective tissue. However, because ery- prolonged exposure of the feet to wet conditions.15 sipelas can extend to deeper tissues and cellulitis can However, pitted keratolysis may also develop in extend superficially, the distinction between the two people with pre-existing hyperhidrosis. The presence conditions is somewhat vague. For the sake of sim- of the bacteria leads to the formation of hyperhidrotic plicity, the term cellulitis is now commonly used to crateriform pits on the plantar surface of the heel and encompass both conditions.17 Cellulitis is common in forefoot, which may coalesce to form irregularly older people, with incidence rates ranging from 4 to shaped erosions (Fig. 5.7). The skin develops a char- 25 cases per 10 000 person-years in those aged over acteristic ‘sliminess’ and is accompanied by a pungent 65 years.44 The most common bacterium responsible odour.57 Most cases are asymptomatic. Treatment for cellulitis is Streptococcus pyogenes, followed by involves the application of astringent foot soaks or Staphylococcus aureus.45 Anaerobic organisms such as powders, and topical antibiotics.15,58 Peptostreptococcus, Clostridium and Porphyromonas are occasionally isolated from affected skin.46 TINEA PEDIS Fungal infection of the foot (tinea pedis) is extremely common in older people. Epidemiological studies

84 OTHER SKIN DISORDERS A Figure 5.7 Pitted keratolysis affecting the heel. (Courtesy of Lesley Newcombe, La Trobe University.) B their ability to penetrate the stratum corneum. For foot infections, the most common infective organisms Figure 5.6 Cellulitis. A. Acute cellulitis associated with are Trichophyton rubrum, Trichophyton mentagrophytes an infected plantar callus. (Courtesy of Matthew Dilnot, (also known as Trichophyton interdigitale) and Epider- Melbourne Foot Clinic.) B. Chronic cellulitis associated mophyton floccosum.60 The presence of these organ- with venous ulceration. (Courtesy of Lesley Newcombe, isms in the skin causes keratin destruction and an La Trobe University.) inflammatory response, leading to the characteristic signs of erythema and desquamation and the common indicate that between 5% and 20% of community- presenting complaint of severe pruritus. There are dwelling people aged over 65 years have some form three major types of fungal skin infection: interdigital of fungal infection.10,59 The Achilles Foot Screening tinea pedis, which develops between the toes and has Project, which involved clinical examination of the a moist, macerated, scaly appearance, moccasin foot, feet of people attending dermatologists or primary characterised by a hyperkeratotic, dry scaling of the care physicians in 16 countries,14 indicated that the lateral and plantar surfaces of the foot, and vesicular second most commonly diagnosed condition in older (or bullous) tinea pedis, in which vesicles or bullae people was fungal infection of the skin, which was filled with clear fluid develop on the plantar surface observed in 29% of the sample.60 A follow-up study or interdigital spaces. A fourth category, ulcerative involving 90 085 older patients across all the partici- tinea pedis, may develop when longstanding interdigi- pating European countries61 reported that almost half tal tinea pedis extends on to the dorsal or plantar had clinical evidence of fungal foot infection. surfaces of the foot. In older people, the most common form is interdigital tinea pedis, which is often trig- Fungal skin infections are caused by a group of gered by inadequate drying between the toes and fungi known as dermatophytes, so named because of occlusion of the interdigital spaces by toe deformity and/or ill-fitting footwear. Interdigital tinea pedis is also commonly associated with concurrent fungal nail infection (onychomycosis) in older people (Fig. 5.8), and, as stated previously, is a significant risk factor for bacterial cellulitis.47–49 First-line treatment of tinea pedis involves the application of topical antifungal medications. Several

Tumours, cysts and lesions 85 Oral medications for fungal infections of the skin first became available in 1958 in the form of griseo- fulvin.63 Although widely used, griseofulvin was not effective against non-dermatophyte fungi and was associated with gastrointestinal side-effects. More recent oral medications, such as the azoles (ketocon- azole, itraconazole and fluconazole) and allylamine (terbinafine) are considerably more effective. The most recent Cochrane review of 12 randomised con- trolled trials concluded that terbinafine is more effec- tive than griseofulvin, and that terbinafine and itraconazole are more effective than a placebo.64 Mycological cure rates with terbinafine (250 mg/d for 4–6 weeks) range from 65% to 100%. An additional consideration when managing A fungal infections in older people is that the likelihood of recurrence is high, particularly if no change is made to the older person’s footwear and hosiery. It is therefore generally recommended that infected footwear and hosiery be discarded as part of the man- agement plan, and that particular emphasis is placed on maintaining adequate foot hygiene such as drying between the toes and regularly changing socks or stockings. TUMOURS, CYSTS AND LESIONS B The foot is a relatively common site for a wide range Figure 5.8 Tinea pedis. A. Interdigital. (Courtesy of of skin lesions in older people, although the actual Lloyd Reed, Queensland University of Technology.) incidence of such lesions is extremely difficult to B. Secondary to onychomycosis. (Courtesy of Lesley determine because of under-reporting and misdiag- Newcombe, La Trobe University.) nosis. Audits of pathology laboratories, however, provide a reasonable estimate of the relative, if not such medications have been developed, including absolute, frequency of different lesions. For lesions allylamines, azoles, undecenoic acid and tolnaftate. affecting the foot, a recent publication by Berlin65 is The recent Cochrane review of 72 randomised con- particularly informative. This paper reports the even- trolled trials62 concluded that allylamines, azoles and tual pathology diagnosis of 307 601 specimens sub- undecenoic acid were all effective compared to a mitted to a podiatry-specific pathology laboratory in placebo, with allylamines curing slightly more infec- the USA, and indicates that verrucae are by far the tions than the azoles. However, because allylamines most commonly biopsied skin lesion affecting the are more expensive, the authors recommended that foot, followed by inclusion cysts and ganglionic cysts the most cost-effective approach is to first treat with (see Table 5.2). Unfortunately, no age breakdown azoles or undecenoic acid, and to use allylamines only was undertaken, so the relative incidence of skin if that fails. Cure rates of 65–91% have been reported; lesions in older people cannot be determined. however, it is likely that the cure rate is somewhat lower in older people. While many of these conditions are asymptomatic when located elsewhere on the body, foot lesions are frequently problematic due to the foot’s weightbear- ing role and the potential for friction from footwear and hosiery. The following section provides a brief overview of some of the more commonly encountered

86 OTHER SKIN DISORDERS Table 5.2 Incidence of skin lesions biopsied placebo-controlled trials of cryotherapy have been from the foot by podiatrists in the continental undertaken, with both reporting no difference in cure USA, Hawaii and Puerto Rico (n = 307 601) rates between the groups.69 Lesion Number (%) Acrochordons Verrucae 176 053 (57.2) Acrochordons, also referred to as skin tags or cutane- Inclusion cysts 7 558 (2.4) ous tags, appear as soft, skin-coloured polyps with a Ganglion cysts 7 395 (2.4) smooth to pedunculated surface (Fig. 5.10). On non- Fibromas 1 779 (0.6) weightbearing areas (most commonly the neck, chest Dermatofibromas 1 701 (0.6) and axillae), the lesion extends from the skin surface Mucous (myxoid) cysts 1 227 (0.4) on a small stalk; however, if located on the plantar Hemangiomas 594 (0.2) surface of the foot, compression results in a flatter Squamous cell carcinomas 312 (0.1) lesion that may be covered with hyperkeratosis. Treat- ment is rarely necessary but if the lesion is painful it lesions affecting the older foot, divided into benign can easily be removed with a scalpel followed by elec- lesions and premalignant or malignant lesions. trocautery of the base of the lesion.70 BENIGN LESIONS Cutaneous horns Verrucae Cutaneous horns, also known as onychoma, are kera- totic lesions that project outwards from the skin in Plantar verrucae (warts) are very common benign epi- the shape of an animal horn and are commonly found dermal neoplasms caused by various strains of the on the ears, hands and feet in older people (Fig. human papilloma virus. Verrucae can develop at any 5.11).71 Cutaneous horns can develop from a wide age but are more common in children and adoles- range of pre-existing dermatological lesions, includ- cents.66,67 The appearance of verrucae can be highly ing verrucae and stucco keratoses. Because of their variable, from smooth, flesh-coloured papules through size, cutaneous horns are frequently painful, and in to raised nodules with a cauliflower-like surface. The older people there is a risk of malignancy at the base most characteristic features of verrucae are the disrup- of the lesion. Treatment involves debridement of the tion of normal skin lines and the presence of throm- lesion followed by curettage or cryotherapy.72 bosed capillaries within the lesion. These features can assist in differentiating verrucae from corns or cal- Dermatofibromas luses. In immunocompromised patients, multiple ver- rucae may form into clusters (known as mosaic Dermatofibromas are firm, raised, pigmented lesions verrucae), which often develop overlying hyperkera- ranging in size from a few millimetres to 1 cm in tosis (Fig. 5.9). Verrucae are generally self-limiting diameter, and most commonly occur in middle aged and will spontaneously regress over a period of months and older people. The lesions can develop anywhere or years.68 However, verrucae on the foot can be quite on the body; however, the lower limbs are affected painful and often require treatment. more frequently than the upper limbs or trunk (Fig. 5.12). Treatment is generally not necessary as the A plethora of verrucae treatments have been re- lesions are rarely symptomatic, and malignant changes ported in the literature, from various topical agents are extremely rare.73 (glutaraldehyde, formaldehyde, podophyllin, podo- phyllotoxin, silver nitrate, salicylic acid, monochloro- Figure 5.9 A. Large verruca pedis under the first acetic acid and phenol) and intralesional injections metatarsophalangeal joint following debridement of (bleomycin, 5-fluorouracil) through to cryotherapy, overlying callus. B. Close-up view showing thrombosed CO2 laser and electrodesiccation with curettage. The capillaries. C. Subungual verruca. D. Mosaic verrucae. most recent Cochrane systematic review of 60 trials (Courtesy of Lesley Newcombe, La Trobe University.) concluded that topical application of 15–20% salicylic acid is the most effective treatment for verrucae, with a cure rate of 75%. Somewhat surprisingly, only two

Tumours, cysts and lesions 87 AB CD

88 OTHER SKIN DISORDERS Figure 5.12 Dermatofibroma. (Courtesy of Lesley Newcombe, La Trobe University.) Figure 5.10 Acrochordon (skin tag) on the lateral aspect of the hallux. (Courtesy of Lesley Newcombe, La Trobe University.) Figure 5.13 Epidermal inclusion cyst. (With permission from Dockery GL, Crawford ME. Cutaneous disorders of the lower extremity. Philadelphia: WB Saunders; 1997.) Figure 5.11 Cutaneous horn on the plantar surface of Coulter & Bouche74 have also described three cases the foot. (With permission from Dockery GL, Crawford ME. of epidermal inclusion cysts developing from ill-fitting Cutaneous disorders of the lower extremity. Philadelphia: footwear. The lesions have a dome-like appearance WB Saunders; 1997.) with a thin cover of epidermis and may develop a layer of hyperkeratosis. Occasionally the lesion may drain, Epidermal inclusion cysts extruding a thick, foul-smelling keratin material. Treatment is generally not required but, if considered These cysts most commonly affect people over the age necessary, involves surgical excision.15 of 60 years and develop as a result of a portion of epidermis becoming implanted, either surgically or Ganglion cysts traumatically, into the underlying dermis (Fig. 5.13). Ganglion cysts, or ganglia, are generally asympto- matic, fluctuant lesions that most commonly develop in the wrists but may also affect the lower limb (Fig.

Tumours, cysts and lesions 89 involves corticosteroid injection (with or without aspiration of the contents of the cyst); however, if the lesions become large and painful, surgical excision may be indicated. A retrospective review of 63 gan- glion treatments by Pontious et al76 reported a recur- rence rate of 63% in those managed conservatively and 11% in those treated surgically. A very similar recur- rence rate (61%) with conservative intervention was reported by Mallick et al;77 however, the authors also stated that the recurrent lesions were far less symp- tomatic than the original lesions and required no further treatment. Haemangiomas Haemangiomas (also referred to as senile haemangio- A mas) are smooth, bright red, dome-like lesions that most commonly affect the head and neck but can also appear on the plantar surface of the foot or the toes (Fig. 5.15). The characteristic colour of the lesion is due to the presence of multiple dilated blood vessels. They rarely require treatment but can be removed by excision or electrodesiccation.78 B Keratoacanthomas Figure 5.14 Ganglion cysts. A. Lateral aspect of the ankle. (Courtesy of Lesley Newcombe, La Trobe Most commonly observed on the head and neck of University.) B. Base of fifth metatarsal. (Courtesy of older people, keratoacanthomas are smooth, red, Lloyd Reed, Queensland University of Technology.) dome-like papules that range in size from a few mil- limetres to a few centimetres in diameter and can 5.14). Approximately two-thirds of ganglia in the occasionally form on the foot (Fig. 5.16). Subungual lower limb are found on the foot, the most common lesions are often painful and tend to penetrate more sites being the dorsolateral aspect of the ankle and the deeply than lesions in other areas because of dorsal hallux.75 The cysts contain a fluid similar to synovium compression from the nail. In long-standing cases, the thought to be derived from the adjacent tendon nail plate may separate from the nail bed at its distal sheaths or joint capsules. Conservative treatment edge and the distal phalanx may develop a crescent- shaped erosion easily visible on radiographs. Because it is often difficult to differentiate keratoacanthomas from squamous cell carcinomas, surgical excision is recommended.79 Mucoid cysts Also referred to as myxoid cysts or synovial cysts, mucoid cysts are soft, dome-like, oval lesions that form within the dermis and contain a straw-coloured, viscous fluid (Fig. 5.17).80 In the foot, mucoid cysts are most com- monly located proximal to the nail fold and are thought to be caused by the herniation of the exten- sor tendon sheath or joint capsule. Large cysts may create difficulties with footwear and, if the lesion

90 OTHER SKIN DISORDERS Figure 5.15 Cherry hemangioma. (With permission from Dockery GL, Crawford ME. Cutaneous disorders of the lower extremity. Philadelphia: WB Saunders; 1997.) Figure 5.17 Mucoid cyst. (With permission from Dockery GL, Crawford ME. Cutaneous disorders of the lower extremity. Philadelphia: WB Saunders Company; 1997.) malignant melanoma is a higher than average number of melanocytic naevi.82 Figure 5.16 Keratoacanthoma. (With permission from Piezogenic pedal papules DermNet NZ, www.dermnetnz.org. Copyright © 2007 Interactive Medical Media LLC, All rights reserved.) These common lesions develop around the periphery of the heel and appear as skin-coloured, soft hernia- penetrates the nail matrix, the nail plate may become tions of fat when weightbearing (Fig. 5.18). Piezo- dystrophic. Treatment involves cryotherapy, cortico- genic pedal papules are thought to be protrusions of steroid injection or excision.81 loculated fat extending through connective tissue irregularities in the dermis. The lesions are rarely Naevi symptomatic but may become painful in people who are overweight or in response to prolonged standing. Naevi (‘moles’) are pigmented lesions that are highly Treatment involves the use of rigid heel cups to variable in appearance, from firm, slightly elevated prevent lateral spread of the heel pad, or surgical brown papules through to raised, verruciform nodules excision.83 that may contain hair follicles. A brief summary of the more common presentations of naevi is provided Stucco keratoses in Table 5.3. Treatment is generally not necessary. However, all naevi need to be regularly monitored Commonly observed on the dorsum of the foot in for changes in size, shape or colour, which may be older people, stucco keratoses are white to yellow, indicative of malignant changes. It has also been dry, scaly lesions up to 1 cm in diameter that can demonstrated that one of the strongest predictors of occasionally be peeled off the underlying skin (Fig. 5.19). In some cases the lesions may have a cauli- flower appearance.84 The cause is unknown; however, a recent study reported the presence of human papil- loma virus DNA in the lesions of an immunocompro- mised older patient.85 Treatment involves application

Tumours, cysts and lesions 91 Table 5.3 Common presentations of naevi Location Type Appearance Junctional melanotic naevocellular Small (<1 cm) circumscribed round Trunk, face, upper and lower limbs, naevus brown macule with regular borders palmar and plantar surfaces Compound melanotic naevocellular Trunk, face, scalp, upper and lower naevus Round, dome-shaped papule or nodule, limbs Dermal melanotic naevocellular may be papillomatous or hyperkeratotic Face, neck, upper and lower limbs naevus Round, dome-shaped, skin coloured, tan Trunk Halo naevomelanocytic naevus or brown papule or nodule. Older lesions may be papillomatous or pedunculated Dorsum of hands and feet Blue naevus Oval or round brown papule with white ‘halo’ of hypomelanosis Oval or round, dark blue to grey-black, firm papule or nodule <1 cm Figure 5.19 Stucco keratoses. (Courtesy of Lloyd Reed, Queensland University of Technology.) Figure 5.18 Piezogenic papules. (With permission from located on the posterolateral aspect of the heel. The Dockery GL. Color atlas of foot and ankle dermatology. lesions are caused by lateral shearing of the papillary Philadelphia: Lippincott-Raven; 1999.) dermis, resulting in intraepidermal haemorrhage and the formation of multiple, pin-point macules, which of emollient or vitamin D3 creams,86 electrodesicca- may coalesce to form a dark irregular patch (Fig. tion or curettage; however, the lesions tend to return 5.20). Calcaneal petechiae are most commonly found after a few months.84 in young athletes; however, they do occur in older people and can be mistaken for verrucae or malignant Calcaneal petechiae melanoma. Often covered by or embedded in hyper- keratosis, the lesion may be cleared by scalpel debride- Commonly referred to as black heel, calcaneal pete- ment. However, no treatment is necessary and the chiae are benign, trauma-induced lesions typically lesions usually resolve over a period of weeks or months.87,88

92 OTHER SKIN DISORDERS Figure 5.20 Calcaneal petechiae. (Courtesy of Lesley Figure 5.21 Actinic keratoses. (Courtesy of Lloyd Reed, Newcombe, La Trobe University.) Queensland University of Technology.) PREMALIGNANT AND mnemonic (A = asymmetry, B = border irregularity, MALIGNANT LESIONS C = change in colour and D = increase in diameter) is a useful general rule for routine clinical assessment Over the past six decades, the incidence of skin cancer of lesions95 and has been found to be highly sensitive has dramatically increased throughout the world.89 In and specific in differentiating between benign and the USA, 1.3 million people were diagnosed with skin malignant lesions.96 cancer in 2002, including 900 000 cases of basal cell carcinoma, 300 000 cases of squamous cell carcinoma The following section provides an overview and 53 000 cases of malignant melanoma.90 Incidence of some of the more common premalignant and rates are even higher in countries with very high levels malignant lesions that may develop on the older of sun exposure, such as South Africa and Australia.91 foot. In addition to level of sun exposure, the key risk factors for skin cancer are a positive family history, fair Actinic keratoses complexion, presence of dysplastic naevi (atypical moles) or actinic keratoses and a higher than average Actinic keratoses, also known as solar dermatoses or number of naevi.91 Mortality rates associated with skin senile keratoses, are the most common premalignant cancer are particularly high in men and increase mark- epidermal lesions in older people, affecting 45% of edly over the age of 60 years.92 men and 35% of women aged over 65 years.1 The lesions are well circumscribed raised papules or plaques The foot is not a common site for the development and have a dry, scaly surface. Although actinic kera- of premalignant or malignant lesions, as footwear pro- toses most commonly affect areas of sun-exposed vides some protection from sun exposure. However, skin, such as the head, neck, face and arms, they can malignancies that do develop on the foot are subject also develop on the legs and feet (see Fig. 5.21). to delayed or incorrect diagnosis, which may explain These lesions should be carefully monitored as they the higher mortality rate of foot lesions compared to may degenerate into squamous cell carcinomas. lesions located elsewhere.93,94 It is therefore essential Indeed, because the rate of conversion is so high, a that all clinicians involved in the management of foot number of authors have argued that actinic keratoses disorders thoroughly examine, monitor and docu- are simply an early stage of squamous cell carcinoma ment suspect lesions in older patients and provide and should be relabelled accordingly.97,98 Treatment timely referrals to dermatologists or oncologists where involves topical application of 5-fluorouracil or diclof- necessary. As stated in Chapter 3, the simple ABCD enac sodium, or destruction of the lesion using cryo- therapy or electrodesiccation.99,100

Tumours, cysts and lesions 93 Figure 5.23 Bowen’s disease. (Courtesy of Karl Landorf, La Trobe University.) Figure 5.22 Arsenical keratoses. (With permission from of life.102 The lesion is a well-defined, raised, irregular Dockery GL, Crawford ME. Cutaneous disorders of the plaque with superficial crusting that most commonly lower extremity. Philadelphia: WB Saunders Company; develops on sun-exposed areas of skin (Fig. 5.23). On 1997.) the foot, the plantar surface is the most common site, although lesions have also been reported on the Arsenical keratoses dorsum of the foot or between the toes.103–105 Although the lesion may become malignant, conver- Arsenical keratoses are caused by exposure to inor- sion to squamous cell carcinoma is rare (approxi- ganic arsenic compounds in medications (such as mately 3% of cases).106 Treatment involves topical drugs used for psoriasis and bronchitis in the 1930s application of 5-fluourouracil, cryotherapy, electro- and 1940s), insecticides or drinking water, and appear desiccation or surgical excision. as multiple discrete, yellow, punctuate round lesions on the palms and plantar surface of the foot (Fig. Basal cell carcinoma 5.22). Treatment involves the application of emol- lient creams and keratolytics. Oral administration of With an overall lifetime risk of 30% of the Caucasian acitretin (a medication commonly used for psoriasis) population,1 basal cell carcinoma is the most common in conjunction with intralesional injection of 5-fluo- form of skin cancer. The most common presentation, rouracil has also been reported to be effective.101 As nodular basal cell carcinoma, starts as a small, dome- with actinic keratoses, arsenical keratoses can degen- shaped nodule or papule that expands into an ery- erate into squamous cell carcinomas. thematous, blue-black lesion with a pearly translucent border. Other variants include cystic basal cell carci- Bowen’s disease noma, which has a lobulated appearance and may contain a clear fluid, pigmented basal cell carcinoma, Bowen’s disease is an epidermal carcinoma sometimes which has a pigmented brown-black border, and referred to as squamous cell carcinoma in situ and is superficial basal cell carcinoma, which is the most most commonly seen in women in the eighth decade common type affecting the foot and appears as red plaque with an adherent scaly surface (Fig. 5.24). Treatment involves cryotherapy, surgical excision or radiotherapy. A recent Cochrane review of 19 trials concluded that both surgical excision and radiother- apy are effective, although surgical excision has a lower failure rate.107

94 OTHER SKIN DISORDERS Figure 5.25 Squamous cell carcinoma on the dorsum of the foot. (Courtesy of Karl Landorf, La Trobe University.) Figure 5.24 Superficial basal cell carcinoma. (Courtesy of Lesley Newcombe, La Trobe University.) Squamous cell carcinoma Figure 5.26 Superficial spreading malignant melanoma. (With permission from DermNet NZ, www.dermnetnz.org. Squamous cell carcinoma is the second most common Copyright © 2007 Interactive Medical Media LLC, All form of skin cancer, with 59% of cases occurring in rights reserved.) people aged over 65 years.1 The lesion is a sharply demarcated, scaly or crusted, erythematous plaque ing malignant melanoma, the most common form most commonly found on the head and neck or other which appears as a flat plaque with an irregular border sun-exposed areas of the skin. Although foot involve- (Fig. 5.26), nodular malignant melanoma, which ment is rare (approximately 2% of cases), squamous appears as a firm, blueberry-coloured nodule, lentigo cell carcinomas can develop on the dorsum of the maligna, a broad, brown lesion most commonly foot,108,109 the heel,110 beneath the nail plate111–114 or found on the head and neck, and acral lentiginous interdigitally115 (Fig. 5.25). When the toes are affected, malignant melanoma, which are commonly misdiag- the condition can easily be misdiagnosed as an infec- nosed as subungual haematomas or verrucae. In the tion. Longstanding chronic ulcers, scars, non-healing foot, the most commonly affected sites are the plantar verrucae and sinuses in older people may also undergo surface, followed by the dorsum and beneath the nail malignant changes and develop into a secondary form plate.94,118–121 Treatment involves surgical excision and of squamous cell carcinoma (referred to as Marjolin’s adjunctive chemotherapy. ulcer). Because of the risk of metastasis, treatment involves wide surgical excision. Malignant melanoma The most lethal form of skin cancer, malignant mela- noma comprises only 5% of all skin cancers but accounts for three-quarters of all skin-cancer-related deaths.116 Foot involvement is not common (fewer than 10% of cases),117 however the consequences of misdiagnosis are serious, with survival rates of primary melanoma of the foot and ankle being much lower than other lower limb sites.93,94,118–120 There are four main types of malignant melanoma: superficial spread-

References 95 SUMMARY diagnosis of these conditions and providing informed referrals where necessary. Finally, although the foot is The foot is a relatively common site for the develop- not a common site for the development of skin malig- ment of skin lesions in older people. Many of these nancies, all clinicians involved in the management of lesions are asymptomatic and may not require treat- foot problems should have a high index of suspicion ment, while other conditions are best managed of non-healing or changeable lesions on the foot in by dermatologists. However, all foot-care specialists older people. should be capable of establishing at least a provisional References 13. Crawford VLS, Ashford RL, McPeake B et al. Con- servative podiatric medicine and disability in elderly 1. Society for Investigative Dermatology, American people. Journal of the American Podiatric Medical Academy of Dermatology Association. The burden Association 1995; 85: 255–259. of skin diseases 2004. Cleveland: Society for Inves- tigative Dermatology and American Academy of 14. Haneke E. Achilles foot-screening project: back- Dermatology Association; 2006. ground, objectives and design. Journal of the Euro- pean Academy of Dermatology and Venereology 2. Young AW. Dermatologic complaints presented 1999; 12: S2–5. by geriatric inpatients. Geriatrics 1958; 13: 428– 434. 15. Dockery GL, Crawford ME. Cutaneous disorders of the lower extremity. Philadelphia, PA: WB Saunders; 3. Adam JE, Reilly S. The prevalence of skin disease in 1997. the geriatric age group. Australasian Journal of Der- matology 1987; 28: 72–76. 16. Mason AR, Cork MJ, Dooley G et al. Topical treat- ments for chronic plaque psoriasis (Protocol). 4. Yap KB, Siew MG, Goh CL. Pattern of skin disease Cochrane Database of Systematic Reviews 2006; in the elderly seen at the National Skin Centre 3: CD005028. (Singapore) 1990. Singapore Medical Journal 1994; 35: 147–150. 17. Kilburn S, Featherstone P, Higgins B et al. Interven- tions for cellulitis and erysipelas (Protocol). Cochrane 5. Liao YH, Chen KH, Tseng MP et al. Pattern of skin Database of Systematic Reviews 2006; 1: diseases in a geriatric patient group in Taiwan: a 7- CD004299. year survey from the outpatient clinic of a university medical center. Dermatology 2001; 203: 308–313. 18. Gupta AK, Inniss K, Wainwright R et al. Interven- tions for actinic keratoses (Protocol). Cochrane 6. Yalcin B, Tamer E, Toy GG et al. The prevalence of Database of Systematic Reviews 2006; 4: skin diseases in the elderly: analysis of 4099 geriatric CD004415. patients. International Journal of Dermatology 2006; 45: 672–676. 19. Sladden MJ, Barzilai DA, Berg D et al. Surgical excision margins for localised cutaneous melanoma 7. Smith D, Leggat PA. Prevalence of skin disease (Protocol). Cochrane Database of Systematic among the elderly in different clinical environments. Reviews 2004; 3: CD004835. Australasian Journal on Ageing 2005; 24: 71–76. 20. Herd R, Jury C. Topical 5 fluorouracil for non-mela- 8. Elton PJ, Sanderson SP. A chiropodial survey of noma skin cancer (Protocol). Cochrane Database of elderly persons over 65 years in the community. Systematic Reviews 2000; 3: CD003084. Public Health 1986; 100: 219–232. 21. Norman RA. Xerosis and pruritus in the elderly: 9. Black JR, Hale WE. Prevalence of foot complaints recognition and management. Dermatologic Therapy in the elderly. Journal of the American Podiatric 2003; 16: 254–259. Medical Association 1987; 77: 308–311. 22. Paniker P. Images in dermatology. American Journal 10. Dunn JE, Link CL, Felson DT et al. Prevalence of of Medicine 2005; 118: 108. foot and ankle conditions in a multiethnic commu- nity sample of older adults. American Journal of 23. Moses S. Pruritus. American Family Physician 2003; Epidemiology 2004; 159: 491–498. 68: 1135–1142. 11. Brodie BS, Rees CL, Robins DJ et al. Wessex Feet: 24. London NJM, Nash R. Varicose veins. British a regional foot health survey, Volume I: The survey. Medical Journal 2000; 320: 1391–1394. Chiropodist 1988; 43: 152–165. 25. Quartey-Papafio CM. Importance of distinguish- 12. Greenberg L. Foot care data from two recent nation- ing between cellulitis and varicose eczema of the wide surveys. A comparative analysis. Journal of the leg. British Medical Journal 1999; 318: 1672– American Podiatric Medical Association 1994; 84: 1673. 365–370.