Journal of Foot and Ankle Research - Most accessed articles

Visual categorisation of the arch index: a simplified measure of foot posture in older people

Hylton Menz — 2012-04-23T00:00:00Z

Background: Foot posture is considered to be an important component of musculoskeletal assessment in clinical practice and research. However, many measurement approaches are not suitable for routine use as they are time-consuming or require specialised equipment and/or clinical expertise. The objective of this study was therefore to develop and evaluate a simple visual tool for foot posture assessment based on the arch index (AI) that could be used in clinical and research settings. Methods: Fully weightbearing footprints from 602 people aged 62 to 96 years were obtained using a carbon paper imprint material, and cut-off AI scores dividing participants into three categories (high, normal and low) were determined using the central limit theorem (i.e. normal = +/ 1 standard deviation from the mean). A visual tool was then created using representative examples for the boundaries of each category. Two examiners were then asked to use the tool to independently grade the footprints of 60 participants (20 for each of the three categories, randomly presented), and then repeat the process two weeks later. Inter- and intra-tester reliability was determined using Spearman's rho, percentage agreement and weighted kappa statistics. The validity of the examiner's assessments was evaluated by comparing their categorisations to the actual AI score using Spearman's rho and analysis of variance (ANOVA), and to the actual AI category using percentage agreement, Spearman's rho and weighted kappa. Results: Inter- and intra-tester reliability of the examiners was almost perfect (percentage agreement = 93 to 97%; Spearman's rho = 0.91 to 0.95, and weighted kappas = 0.85 to 0.93). Examiners' scores were strongly correlated with actual AI values (Spearman's rho = 0.91 to 0.94 and significant differences between all categories with ANOVA; p < 0.001) and AI categories (percentage agreement = 95 to 98%; Spearman's rho = 0.89 to 0.94, and weighted kappas = 0.87 to 0.94). There was a slight tendency for examiners to categorise participants as having higher arches than their AI scores indicated. Conclusions: Foot posture can be quickly and reliably categorised as high, normal or low in older people using a simplified visual categorisation tool based on the AI.

Comparison of shoe-length fit between people with and without diabetic peripheral neuropathy: a case-control study

Alistair McInnes — 2012-04-16T00:00:00Z

Background: Amongst the many identified mechanisms leading to diabetic foot ulceration, ill-fitting footwear is one. There is anecdotal evidence that people with diabetic peripheral neuropathy wear shoes that are too small in order to increase the sensation of fit. The aim of this study was to determine whether people with diabetic sensory neuropathy wear appropriate length footwear. Methods: A case-control design was used to compare internal shoe length and foot length differences between a group of people with diabetes and peripheral sensory neuropathy and a group of people without diabetes and no peripheral sensory neuropathy. Shoe and foot length measurements were taken using a calibrated Internal Shoe Size Gauge(R) and a Brannock Device(R), respectively. Results: Data was collected from 85 participants with diabetes and 118 participants without diabetes. The mean difference between shoe and foot length was not significantly different between the two groups. However, a significant number of participants within both groups had a shoe to foot length difference that lay outside a previously suggested 10 to 15 mm range. From the diabetic and non-diabetic groups 82% (70/85) and 66% (78/118), respectively had a foot to shoe length difference outside this same range. Conclusions: This study shows that although there is no significant difference in shoe-length fit between participants with and without neuropathy, a significant proportion of these populations wear shoes that are either too long or too short for their foot length according to the 10 to 15 mm value used for comparison. The study has highlighted the need for standardised approaches when considering the allowance required between foot and internal shoe length and for the measurement and comparison of foot and shoe dimensions.

Altering gait by way of stimulation of the plantar surface of the foot: the immediate effect of wearing textured insoles in older fallers

Anna Hatton — 2012-04-30T00:00:00Z

Background: Evidence suggests that textured insoles can alter gait and standing balance by way of enhanced plantar tactile stimulation. However, to date, this has not been explored in older people at risk of falling. This study investigated the immediate effect of wearing textured insoles on gait and double-limb standing balance in older fallers. Methods: Thirty older adults >65 years (21 women, mean [SD] age 79.0 [7.1]), with self-reported history of [greater than or equal to]2 falls in the previous year, conducted tests of level-ground walking over 10 m (GAITRite system), and double-limb standing with eyes open and eyes closed over 30 seconds (Kistler force platform) under two conditions: wearing textured insoles (intervention) and smooth (control) insoles in their usual footwear. Results: Wearing textured insoles caused significantly lower gait velocity (P = 0.02), step length (P = 0.04) and stride length (P = 0.03) compared with wearing smooth insoles. No significant differences were found in any of the balance parameters (P > 0.05). Conclusions: A textured insole worn by older adults with a history of falls significantly lowers gait velocity, step length and stride length, suggesting that this population may not have an immediate benefit from this type of intervention. The effects of prolonged wear remain to be investigated.

Tibialis posterior in health and disease: a review of structure and function with specific reference to electromyographic studies

Ruth Semple — 2009-08-19T00:00:00Z

Tibialis posterior has a vital role during gait as the primary dynamic stabiliser of the medial longitudinal arch; however, the muscle and tendon are prone to dysfunction with several conditions. We present an overview of tibialis posterior muscle and tendon anatomy with images from cadaveric work on fresh frozen limbs and a review of current evidence that define normal and abnormal tibialis posterior muscle activation during gait. A video is available that demonstrates ultrasound guided intra-muscular insertion techniques for tibialis posterior electromyography.Current electromyography literature indicates tibialis posterior intensity and timing during walking is variable in healthy adults and has a disease-specific activation profile among different pathologies. Flat-arched foot posture and tibialis posterior tendon dysfunction are associated with greater tibialis posterior muscle activity during stance phase, compared to normal or healthy participants, respectively. Cerebral palsy is associated with four potentially abnormal profiles during the entire gait cycle; however it is unclear how these profiles are defined as these studies lack control groups that characterise electromyographic activity from developmentally normal children. Intervention studies show antipronation taping to significantly decrease tibialis posterior muscle activation during walking compared to barefoot, although this research is based on only four participants. However, other interventions such as foot orthoses and footwear do not appear to systematically effect muscle activation during walking or running, respectively. This review highlights deficits in current evidence and provides suggestions for the future research agenda.

Classification of the height and flexibility of the medial longitudinal arch of the foot

Mettte Nilsson — 2012-02-17T00:00:00Z

Background: The risk of developing injuries during standing work may vary between persons with different foot types. High arched and low arched feet, as well as rigid and flexible feet, are considered to have different injury profiles, while those with normal arches may sustain fewer injuries. However, the cut-off values for maximum values (subtalar position during weight-bearing) and range of motion (ROM) values (difference between subtalar neutral and subtalar resting position in a weight-bearing condition) for the medial longitudinal arch (MLA) are largely unknown. The purpose of this study was to identify cut-off values for maximum values and ROM of the MLA of the foot during static tests and to identify factors influencing foot posture. Methods: The participants consisted of 254 volunteers from Central and Northern Denmark (198 m/56 f; age 39.0 ± 11.7 years; BMI 27.3 ± 4.7 kg/m2). Navicular height (NH), longitudinal arch angle (LAA) and Feiss line (FL) were measured for either the left or the right foot in a subtalar neutral position and subtalar resting position. Maximum values and ROM were calculated for each test. The 95% and 68% prediction intervals were used as cut-off limits. Multiple regression analysis was used to detect influencing factors on foot posture. Results: The 68% cut-off values for maximum MLA values and MLA ROM for NH were 3.6 to 5.5 cm and 0.6 to 1.8 cm, respectively, without taking into account the influence of other variables. Normal maximum LAA values were between 131 and 152° and normal LAA ROM was between -1 and 13°. Normal maximum FL values were between -2.6 and -1.2 cm and normal FL ROM was between -0.1 and 0.9 cm. Results from the multivariate linear regression revealed an association between foot size with FL, LAA, and navicular drop. Conclusions: The cut-off values presented in this study can be used to categorize people performing standing work into groups of different foot arch types. The results of this study are important for investigating a possible link between arch height and arch movement and the development of injuries.

Clinical guidelines for the recognition of melanoma of the foot and nail unit

Ivan Bristow — 2010-11-01T00:00:00Z

Malignant melanoma is a life threatening skin tumour which may arise on the foot. The prognosis for the condition is good when lesions are diagnosed and treated early. However, lesions arising on the soles and within the nail unit can be difficult to recognise leading to delays in diagnosis. These guidelines have been drafted to alert health care practitioners to the early signs of the disease so an early diagnosis can be sought.

A protocol for classifying normal- and flat-arched foot posture for research studies using clinical and radiographic measurements

George Murley — 2009-07-04T00:00:00Z

Background: There are several clinical and radiological methods available to classify foot posture in research, however there is no clear strategy for selecting the most appropriate measurements. Therefore, the aim of this study was to develop a foot screening protocol to distinguish between participants with normal- and flat-arched feet who would then subsequently be recruited into a series of laboratory-based gait studies. Methods: The foot posture of ninety-one asymptomatic young adults was assessed using two clinical measurements (normalised navicular height and arch index) and four radiological measurements taken from antero-posterior and lateral x-rays (talus-second metatarsal angle, talo-navicular coverage angle, calcaneal inclination angle and calcaneal-first metatarsal angle). Normative foot posture values were taken from the literature and used to recruit participants with normal-arched feet. Data from these participants were subsequently used to define the boundary between normal- and flat-arched feet. This information was then used to recruit participants with flat-arched feet. The relationship between the clinical and radiographic measures of foot posture was also explored. Results: Thirty-two participants were recruited to the normal-arched study, 31 qualified for the flat-arched study and 28 participants were classified as having neither normal- or flat-arched feet and were not suitable for either study. The values obtained from the two clinical and four radiological measurements established two clearly defined foot posture groups. Correlations among clinical and radiological measures were significant (p < 0.05) and ranged from r = 0.24 to 0.70. Interestingly, the clinical measures were more strongly associated with the radiographic angles obtained from the lateral view. Conclusion: This foot screening protocol provides a coherent strategy for researchers planning to recruit participants with normal- and flat-arched feet. However, further research is required to determine whether foot posture variations in the sagittal, transverse or both planes provide the best descriptor of the flat foot.

Cost-effectiveness of cryotherapy versus salicylic acid for the treatment of plantar warts: economic evaluation alongside a randomised controlled trial (EVerT trial)

Eugena Stamuli — 2012-02-27T00:00:00Z

Background: Plantar warts (verrucae) are extremely common. Although many will spontaneously disappear without treatment, treatment may be sought for a variety of reasons such as discomfort. There are a number of different treatments for cutaneous warts, with salicylic acid and cryotherapy using liquid nitrogen being two of the most common forms of treatment. To date, no full economic evaluation of either salicylic acid or cryotherapy has been conducted based on the use of primary data in a pragmatic setting. This paper describes the cost-effectiveness analysis which was conducted alongside a pragmatic multicentre, randomised trial evaluating the clinical effectiveness of cryotherapy versus 50% salicylic acid of the treatment of plantar warts. Methods: A cost-effectiveness analysis was undertaken alongside a pragmatic multicentre, randomised controlled trial assessing the clinical effectiveness of 50% salicylic acid and cryotherapy using liquid nitrogen at 12 weeks after randomisation of patients. Cost-effectiveness outcomes were expressed as the additional cost required to completely cure the plantar warts of one additional patient. A NHS perspective was taken for the analysis. Results: Cryotherapy costs on average £101.17 (bias corrected and accelerated (BCA) 95% CI: 85.09-117.26) more per participant over the 12 week time-frame, while there is no additional benefit, in terms of proportion of patients healed compared with salicylic acid. Conclusions: Cryotherapy is more costly and no more effective than salicylic acid.Trial registrationCurrent Controlled Trials ISRCTN18994246 [controlled-trials.com] and National Research Register N0484189151.

Normative values for the Foot Posture Index

Anthony Redmond — 2008-07-31T00:00:00Z

Background: The Foot Posture Index (FPI) is a validated method for quantifying standing foot posture, and is being used in a variety of clinical settings. There have however, been no normative data available to date for comparison and reference. This study aimed to establish normative FPI reference values. Methods: Studies reporting FPI data were identified by searching online databases. Nine authors contributed anonymised versions of their original datasets comprising 1648 individual observations. The datasets included information relating to centre, age, gender, pathology (if relevant), FPI scores and body mass index (BMI) where available. FPI total scores were transformed to interval logit scores as per the Rasch model and normal ranges were defined. Comparisons between groups employed t-tests or ANOVA models as appropriate and data were explored descriptively and graphically. Results: The main analysis based on a normal healthy population (n = 619) confirmed that a slightly pronated foot posture is the normal position at rest (mean back transformed FPI raw score = +4). A 'U' shaped relationship existed for age, with minors and older adults exhibiting significantly higher FPI scores than the general adult population (F = 51.07, p < 0.001). There was no difference between the FPI scores of males and females (2.3 versus 2.5; t = -1.44, p = 0.149). No relationship was found between the FPI and BMI. Systematic differences from the adult normals were confirmed in patients with neurogenic and idiopathic cavus (F = 216.981, p < 0.001), indicating some sensitivity of the instrument to detect a posturally pathological population. Conclusion: A set of population norms for children, adults and older people have been derived from a large sample. Foot posture is related to age and the presence of pathology, but not influenced by gender or BMI. The normative values identified may assist in classifying foot type for the purpose of research and clinical decision making.

Unknotting night-time muscle cramp: a survey of patient experience, help-seeking behaviour and perceived treatment effectiveness

Fiona Blyton — 2012-03-15T00:00:00Z

Background: Night-time calf cramping affects approximately 1 in 3 adults. The aim of this study was to explore the experience of night-time calf cramp; if and where people seek treatment advice; and perceived treatment effectiveness. Methods: 80 adults who experienced night-time calf cramp at least once per week were recruited from the Hunter region, NSW, Australia through newspaper, radio and television advertisements. All participants completed a pilot-tested survey about muscle cramp. Quantitative data were analysed with independent-sample t-tests, Chi square tests and Fisher's tests. Qualitative data were transcribed and sorted into categories to identify themes. Results: Median recalled age of first night-time calf cramp was 50 years. Most participants recalled being awoken from sleep by cramping, and experiencing cramping of either calf muscle, calf-muscle soreness in the days following cramp and cramping during day-time. Despite current therapies, mean usual pain intensity was 66 mm on a 100 mm visual analogue scale. Participants described their cramps as being 'unbearable', 'unmanageable' and 'cruel'. One participant stated that 'sometimes I just wish I could cut my legs open' and another reported 'getting about 2 h sleep a night due to cramps'. Most participants had sought advice about their night-time calf cramps from a health professional. Participants identified 49 different interventions used to prevent night-time calf cramp. Of all treatment ratings, 68% described the intervention used to prevent cramp as being 'useless' or of 'a little help'. Of 14 participants who provided additional information regarding their use of quinine, eight had a current prescription of quinine for muscle cramp at the time of the survey. None had been asked by their prescribing doctor to stop using quinine. Conclusion: Night time calf cramps typically woke sufferers from sleep, affected either leg and caused ongoing pain. Most participants experienced little or no relief with current therapies used to prevent muscle cramp. Most people who were taking quinine for muscle cramp were unaware that the Australian Therapeutic Goods Administration withdrew support of quinine for muscle cramp in 2004 due to the risk of thrombocytopaenia. Case-control studies are required to identify therapeutic targets so that clinical trials can evaluate safe interventions to prevent recurrent cramp.