Effects of gait modifications on tissue-level knee mechanics in individuals with medial tibiofemoral osteoarthritis: A proof-of-concept study towards personalized interventions.

Gait modification is a common nonsurgical approach to alter the mediolateral distribution of knee contact forces, intending to decelerate or postpone the progression of mechanically induced knee osteoarthritis (KOA). Nevertheless, the success rate of these approaches is controversial, with no studies conducted to assess alterations in tissue-level knee mechanics governing cartilage degradation response in KOA patients undertaking gait modifications. Thus, here we investigated the effect of different conventional gait conditions and modifications on tissue-level knee mechanics previously suggested as indicators of collagen network damage, cell death, and loss of proteoglycans in knee cartilage. Five participants with medial KOA were recruited and musculoskeletal finite element analyses were conducted to estimate subject-specific tissue mechanics of knee cartilages during two gait conditions (i.e., barefoot and shod) and six gait modifications (i.e., 0°, 5°, and 10° lateral wedge insoles, toe-in, toe-out, and wide stance). Based on our results, the optimal gait modification varied across the participants. Overall, toe-in, toe-out, and wide stance showed the greatest reduction in tissue mechanics within medial tibial and femoral cartilages. Gait modifications could effectually alter maximum principal stress (~20 ± 7%) and shear strain (~9 ± 4%) within the medial tibial cartilage. Nevertheless, lateral wedge insoles did not reduce joint- and tissue-level mechanics considerably. Significance: This proof-of-concept study emphasizes the importance of the personalized design of gait modifications to account for biomechanical risk factors associated with cartilage degradation.

Controversies in the management of active Charcot neuroarthropathy.

Charcot neuroarthropathy (CN) was first described over 150 years ago. Despite this there remains uncertanity around the factors that contribute to its development, and progression. This article will discuss the current controversies around the pathogenesis, epidemiology, diagnosis, assessment and management of the condition. The exact pathogenesis of CN is not fully understood, and it is likely to be multifactorial, with perhaps currently unknown mechanisms contributing to its development. Further studies are needed to examine opportunities to help screen for and diagnose CN. As a result of many of these factors, the true prevalence of CN is still largely unknown. Almost all of the recommendations for the assessment and treatment of CN are based on low-quality level III and IV evidence. Despite recommendations to offer people with CN nonremovable devices, currently only 40-50% people are treated with this type of device. Evidence is also lacking about the optimal duration of treatment; reported outcomes range from 3 months to more than a year. The reason for this variation is not entirely clear. A lack of standardised definitions for diagnosis, remission and relapse, heterogeneity of populations, different management approaches, monitoring techniques with unknown diagnostic precision and variation in follow-up times prevent meaningful comparison of outcome data. If people can be better supported to manage the emotional and physical consequences of CN, then this could improve people's quality of life and well-being. Finally, we highlight the need for an internationally coordinated approach to research in CN.

A randomised feasibility study of serial magnetic resonance imaging to reduce treatment times in Charcot neuroarthropathy in people with diabetes (CADOM).

AIM: This study aims to explore the feasibility of using serial MRI without contrast in the monitoring of Charcot neuroarthropathy to reduce duration of immobilisation of the foot, in order to decide whether a large-scale trial is warranted. METHODS: A multicentre, randomised, prospective, two arm, open, feasibility study (CADOM) of people with diabetes with a suspected or confirmed diagnosis of Charcot neuroarthropathy. Participants were randomised (1:1) to 'standard care plus', including repeated foot temperature measurements and X-rays, or the intervention arm, with additional three-monthly MRI, until remission of Charcot neuroarthropathy or a maximum 12 months (active phase). Participants were then followed-up for a further 6 months, post remission to monitor for relapse of the Charcot neuroarthropathy (follow-up phase). Feasibility outcomes were recruitment, retention, data completeness, adherence to study procedures and safety of the intervention MRI. We also collected clinical efficacy outcomes, this included time in cast/off-loading device which will be the primary outcome of a future definitive trial. Finally, we collected patient reported outcomes, and data on health and social care usage. RESULTS: One-hundred and five people were assessed for eligibility at five sites. 64/105 potential participants meet the eligibility criteria to participate in the study. Forty-three participants were randomised: 20 to standard care plus and 23 to MRI intervention. The main reason for ineligibility was a previous episode of Charcot neuroarthropathy. Thirteen participants were withdrawn post-randomisation due to an alternative diagnosis being made. Of the remaining 30 participants, 19 achieved remission, 6 had not gone into remission at the end of the 12 month active phase so exited the study. Five participants were lost to follow-up. Of the MRIs that were not disrupted by COVID-19 pandemic 26/31 (84%) were completed. For the visits that were conducted face-to-face, completion rates of patient-reported outcome measures were between 71 and 100%. There were no safety incidents associated with the intervention MRI. As this was a feasibility study it was not designed to test the effectiveness of serial MRI in diagnosing remission. The time in cast/off-loading device was 235 (±108.3) days for the standard care plus arm compared to 292 (±177.4) days for the intervention arm. There was no statistical difference in the time in cast/off-loading device between the two arms of the study: Hazard Ratio (HR) 0.405 (95% CI 0.140-1.172), p = 0.096. DISCUSSION: The findings support a definitive randomised controlled trial to evaluate the effectiveness of MRI in diagnosing remission in Charcot neuroarthropathy. The rates of recruitment, retention, data, and MRI completeness show that a definitive study is feasible. STUDY REGISTRATION: ISRCTN, 74101606 . Registered on 6 November 2017.

Knowledge about foot-specific foot falls risk factors and exercise among physiotherapists in the UK and Portugal: A cross-sectional survey.

BACKGROUND AND PURPOSE: Foot-related falls risk factors and specific foot and ankle exercise interventions are within the scope of Physiotherapy, yet little is known about United Kingdom (UK) and Portugal-based (PT) physiotherapists' self-perceived knowledge, confidence and practice of such interventions, or perceptions of patients' falls prevention knowledge. The purpose of this study was to assess levels of self-reported knowledge, confidence, and practices surrounding foot-specific falls risk and exercise for fall prevention in physiotherapists working in the UK and in Portugal. It also aimed to explore physiotherapists' views about their participants' falls prevention knowledge. METHODS: A self-report online survey was developed, and pilot tested in both nations. Registered Physiotherapists were invited to participate through their professional associations, social media and snowballing. Mann-Whitney tests were used to compare mean ranks of ordinal variables between nations and Chi-square test to assess the independency between pairs of variables. Spearman's correlation coefficient (rs) was used to measure the association between pairs of variables (p < 0.05). RESULTS: 682 physiotherapists participated in the survey [UK n = 229 (mean (SD) age = 43(10) years, 86.9% female]; PT n = 453 (mean (SD) age = 33(9) years, 78.3% female]. Among physiotherapists with a caseload of ≥70% older adults, more PT-based physiotherapists held postgraduate qualifications (p = 0.01). Most physiotherapists correctly identified generic and foot-specific risk factors (≥70% of participants for each item). More UK-based physiotherapists reported always prescribing ankle and foot exercises (42.6% vs. 33%, p =< 0.001) and displayed higher levels of self-reported confidence surrounding exercise-based interventions. DISCUSSION: Our sample of UK and Portugal-based physiotherapists are aware of the contribution of foot-specific risk factors and exercise to falls prevention, with the former group being more confident in exercise-based interventions. Both groups of physiotherapists perceived that their older patients had little knowledge about these topics, with UK older adults having slightly better knowledge on generic falls risk factors at first contact. Future studies and strategies for knowledge translation and education in foot health and foot function screening and management for physiotherapists, within a falls prevention scope, may be informed by this study.

Gait rehabilitation for foot and ankle impairments in early rheumatoid arthritis: a feasibility study of a new gait rehabilitation programme (GREAT Strides).

BACKGROUND: Foot impairments in early rheumatoid arthritis are common and lead to progressive deterioration of lower limb function. A gait rehabilitation programme underpinned by psychological techniques to improve adherence, may preserve gait and lower limb function. This study evaluated the feasibility of a novel gait rehabilitation intervention (GREAT Strides) and a future trial. METHODS: This was a mixed methods feasibility study with embedded qualitative components. People with early (< 2 years) rheumatoid arthritis (RA) and foot pain were eligible. Intervention acceptability was evaluated using a questionnaire. Adherence was evaluated using the Exercise Adherence Rating Scale (EARS). Safety was monitored using case report forms. Participants and therapists were interviewed to explore intervention acceptability. Deductive thematic analysis was applied using the Theoretical Framework of Acceptability. For fidelity, audio recordings of interventions sessions were assessed using the Motivational Interviewing Treatment Integrity (MITI) scale. Measurement properties of four candidate primary outcomes, rates of recruitment, attrition, and data completeness were evaluated. RESULTS: Thirty-five participants (68.6% female) with median age (inter-quartile range [IQR]) 60.1 [49.4-68.4] years and disease duration 9.1 [4.0-16.2] months), were recruited and 23 (65.7%) completed 12-week follow-up. Intervention acceptability was excellent; 21/23 were confident that it could help and would recommend it; 22/23 indicated it made sense to them. Adherence was good, with a median [IQR] EARS score of 17/24 [12.5-22.5]. One serious adverse event that was unrelated to the study was reported. Twelve participants' and 9 therapists' interviews confirmed intervention acceptability, identified perceptions of benefit, but also highlighted some barriers to completion. Mean MITI scores for relational (4.38) and technical (4.19) aspects of motivational interviewing demonstrated good fidelity. The Foot Function Index disability subscale performed best in terms of theoretical consistency and was deemed most practical. CONCLUSION: GREAT Strides was viewed as acceptable by patients and therapists, and we observed high intervention fidelity, good patient adherence, and no safety concerns. A future trial to test the additional benefit of GREAT Strides to usual care will benefit from amended eligibility criteria, refinement of the intervention and strategies to ensure higher follow-up rates. The Foot Function Index disability subscale was identified as the primary outcome for the future trial. TRIAL REGISTRATION: ISRCTN14277030.

A qualitative study to understand people's experiences of living with Charcot neuroarthropathy.

AIMS: Charcot neuroarthropathy (CN) is a complication of neuropathy, in people with diabetes. Treatment requires the prolonged wearing of an offloading device, which can be challenging. The importance of understanding people's perspectives for promoting their engagement in self management is well known. However, no such studies have been done in CN. This qualitative study aimed to understand people's experiences of CN. METHODS: Semi-structured interviews with a purposive sample of 14 participants with CN, recruited from a randomised controlled trial. We gathered opinions, thoughts and the meanings participants attributed to their experiences of CN and its physical, socio-economic and physiological effects and how this affected their families and relationships. We analysed the interviews using Inductive Thematic Analysis. RESULTS: Four analytic themes were identified: (1) 'Trapped at home isolated and missing social life and daily life routines'; (2) 'Disruption to people's roles, responsibilities, relationships and mobility, which people adapted to try and address and manage'; (3) 'Pain which participants related to the direct or indirect consequences of wearing the cast or boot'; and (4) 'Blame for developing CN, attributed to themselves and healthcare professionals'. Participants described guilt about needing more support, expressing frustration, low mood and low self-esteem. CONCLUSION: This study highlights experiential aspects of the previously unrecognised burden of CN. Its physical, social and emotional impacts on participants and their families are substantial and sustained. There is a need to raise clinical awareness of CN and its wider effects. TRIAL REGISTRATION: ISRCTN74101606. Registered on 6 November 2017, http://www.isrctn.com/ISRCTN74101606?q=CADom&filters=&sort=&offset=1&totalResults=1&page=1&pageSize=10&searchType=basic-search.

´Feet are second class citizens`: exploring the perceptions of Scottish and Portuguese older adults about feet, falls and exercise- a qualitative study.

INTRODUCTION: Foot problems are likely to contribute to falls risk in older adults. Foot and ankle exercises may be beneficial, but uptake may be influenced by cultural factors. Few studies have explored the views of older adults from different cultural backgrounds about foot-specific falls risk factors, and foot and ankle falls prevention exercises. OBJECTIVES: To explore the views of Scottish and Portuguese community-dwelling older adults who have experienced a fall, about any foot risk factors for falls, and foot and ankle exercises. METHODS: Cross-cultural qualitative study with (n = 6) focus groups exploring the perceptions of Scottish (n = 10, mean age 76 yrs) and Portuguese older adults (n = 14, mean age 66 years) aged, applying thematic analysis. RESULTS: One main theme `evolving awareness about feet and falls prevention´ and three subthemes; (i) Feet are often forgotten, (ii) the important role of footwear, (iii) need to look at my feet and do the exercises were identified. Scottish participants had more experience of falls prevention but there was a lack of knowledge surrounding foot-specific falls risk factors, and the role of ankle and foot exercise in the prevention of falls. Portuguese participants exhibited a fatalistic approach to falls. CONCLUSIONS: Older adults from both nations had little knowledge of foot-specific falls risk factors, being initially unaware of the functional status of their feet and of the role of exercise in foot care and falls management. There were differences between national groups that should be accounted for when developing culturally adequate interventions.

A randomised feasibility study of serial magnetic resonance imaging to reduce treatment times in Charcot neuroarthropathy in people with diabetes (CADOM): a protocol.

BACKGROUND: Charcot neuroarthropathy is a complication of peripheral neuropathy associated with diabetes which most frequently affects the lower limb. It can cause fractures and dislocations within the foot, which may progress to deformity and ulceration. Recommended treatment is immobilisation and offloading, with a below knee non-removable cast or boot. Duration of treatment varies from six months to more than 1 year. Small observational studies suggest that repeated assessment with magnetic resonance imaging improves decision-making about when to stop treatment, but this has not been tested in clinical trials. This study aims to explore the feasibility of using serial magnetic resonance imaging without contrast in the monitoring of Charcot neuroarthropathy to reduce duration of immobilisation of the foot. A nested qualitative study aims to explore participants' lived experience of Charcot neuroarthropathy and of taking part in the feasibility study. METHODS: We will undertake a two-arm, open study and randomise 60 people with a suspected or confirmed diagnosis of Charcot neuroarthropathy from five NHS, secondary care multidisciplinary Diabetic Foot Clinics across England. Participants will be randomised 1:1 to receive magnetic resonance imaging at baseline and remission up to 12 months, with repeated foot temperature measurements and X-rays (standard care plus), or standard care plus with additional three-monthly magnetic resonance imaging until remission up to 12 months (intervention). Time to confirmed remission of Charcot neuroarthropathy with off-loading treatment (days) and its variance will be used to inform sample size in a full-scale trial. We will look for opportunities to improve the protocols for monitoring techniques and the clinical, patient-centred and health economic measures used in a future study. For the nested qualitative study, we will invite a purposive sample of 10-14 people able to offer maximally varying experiences from the feasibility study to take part in semi-structured interviews to be analysed using thematic analysis. DISCUSSION: The study will inform the decision whether to proceed to a full-scale trial. It will also allow deeper understanding of the lived experience of Charcot neuroarthropathy, and factors that contribute to engagement in management and contribute to the development of more effective patient-centred strategies. TRIAL REGISTRATION: ISRCTN, ISRCTN74101606. Registered on 6 November 2017.

Systematic review of techniques to monitor remission of acute Charcot neuroarthropathy in people with diabetes.

AIM: The management of acute Charcot neuroarthropathy relies on off-loading which is costly and time-consuming. Published studies have used monitoring techniques with unknown diagnostic precision to detect remission. We performed a systematic review of techniques for monitoring response to offloading in acute Charcot neuroarthropathy. MATERIALS AND METHODS: We included studies of off-loading which evaluated or described monitoring techniques in acute Charcot neuroarthropathy. PubMed, EMBASE, CINAHL and Cochrane databases were searched (January1993-July 2018). We extracted data from papers including study design, setting, population, monitoring techniques and treatment outcomes. We also extracted information on the cost, clinical applicability, sensitivity and specificity, safety and participant acceptability of the monitoring techniques. RESULTS: We screened 1205 titles, 140 abstracts and 45 full-texts, and included 29 studies. All studies were of low quality and at high risk of bias. In seven studies, the primary aim was to evaluate monitoring techniques: three evaluated magnetic resonance imaging, two thermography monitoring, one three-phase bone scanning and one Doppler spectrum analysis. The remaining 22 observational studies reported treatment outcomes and described the monitoring techniques used to assess the Charcot neuroarthropathy. Heterogeneity prevented the pooling of data. Very few studies included data on cost, clinical applicability, sensitivity and specificity, safety and patient acceptability of the monitoring techniques used. CONCLUSION: Multiple techniques have been used to evaluate remission in acute Charcot neuroathropathy but uncertainty remains about their effectiveness. We recommend further research into the influences of different monitoring techniques on treatment outcomes.

Motivational interviewing to improve adherence behaviours for the prevention of diabetic foot ulceration.

Diabetic foot ulceration is a major complication associated with high morbidity. Little evidence exists on which interventions are effective at preventing ulceration. Participants who are adherent to self-care behaviours have significantly better outcomes. Motivational interviewing is an intervention that has been used successfully for conditions where adherence is important, such as reduction of obesity and HbA1c levels. A systematic review was conducted to determine whether motivational interviewing is effective at improving adherence for the prevention of Diabetic Foot Ulceration. Electronic searches were run without date or language restrictions in MEDLINE (viaEBSCOhost), CINAHL (viaEBSCOhost), ProQuest (Health and Medical Collection, Nursing and Allied Health Database, PsycINFO, Psychology, PsychArticles), AMED, EMBASE, Cochrane Central Register of Controlled Trials, ScienceDirect, and Web of Science Core Collections. Papers were included if participants had or were at risk of diabetic foot ulceration. Studies required motivational interviewing or a motivational approach as the sole intervention or as a component. Randomised controlled trials and quasi-experimental studies were included if ulceration and/or at least one behavioural outcome was measured before and after the intervention. Five studies met the inclusion criteria. Heterogeneity prevented the pooling of data. One study used motivational interviewing as the sole intervention. This study found a short-term positive effect on footwear adherence. The remaining four studies had a motivational component within their interventions. Two of these studies showed the intervention to be effective but both were at a high risk of bias. This review demonstrates an evidence gap. More research is needed.

Foot pain and foot health in an educated population of adults: results from the Glasgow Caledonian University Alumni Foot Health Survey.

BACKGROUND: Foot pain is common amongst the general population and impacts negatively on physical function and quality of life. Associations between personal health characteristics, lifestyle/behaviour factors and foot pain have been studied; however, the role of wider determinants of health on foot pain have received relatively little attention. Objectives of this study are i) to describe foot pain and foot health characteristics in an educated population of adults; ii) to explore associations between moderate-to-severe foot pain and a variety of factors including gender, age, medical conditions/co-morbidity/multi-morbidity, key indicators of general health, foot pathologies, and social determinants of health; and iii) to evaluate associations between moderate-to-severe foot pain and foot function, foot health and health-related quality-of-life. METHODS: Between February and March 2018, Glasgow Caledonian University Alumni with a working email address were invited to participate in the cross-sectional electronic survey (anonymously) by email via the Glasgow Caledonian University Alumni Office. The survey was constructed using the REDCap secure web online survey application and sought information on presence/absence of moderate-to-severe foot pain, patient characteristics (age, body mass index, socioeconomic status, occupation class, comorbidities, and foot pathologies). Prevalence data were expressed as absolute frequencies and percentages. Multivariate logistic and linear regressions were undertaken to identify associations 1) between independent variables and moderate-to-severe foot pain, and 2) between moderate-to-severe foot pain and foot function, foot health and health-related quality of life. RESULTS: Of 50,228 invitations distributed, there were 7707 unique views and 593 valid completions (median age [inter-quartile range] 42 [31-52], 67.3% female) of the survey (7.7% response rate). The sample was comprised predominantly of white Scottish/British (89.4%) working age adults (95%), the majority of whom were overweight or obese (57.9%), and in either full-time or part-time employment (82.5%) as professionals (72.5%). Over two-thirds (68.5%) of the sample were classified in the highest 6 deciles (most affluent) of social deprivation. Moderate-to-severe foot pain affected 236/593 respondents (39.8%). High body mass index, presence of bunions, back pain, rheumatoid arthritis, hip pain and lower occupation class were included in the final multivariate model and all were significantly and independently associated with moderate-to-severe foot pain (p < 0.05), except for rheumatoid arthritis (p = 0.057). Moderate-to-severe foot pain was significantly and independently associated lower foot function, foot health and health-related quality of life scores following adjustment for age, gender and body mass index (p < 0.05). CONCLUSIONS: Moderate-to-severe foot pain was highly prevalent in a university-educated population and was independently associated with female gender, high body mass index, bunions, back pain, hip pain and lower occupational class. Presence of moderate-to-severe foot pain was associated with worse scores for foot function, foot health and health-related quality-of-life. Education attainment does not appear to be protective against moderate-to-severe foot pain.

A protocol for a randomised controlled trial of prefabricated versus customised foot orthoses for people with rheumatoid arthritis: the FOCOS RA trial [Foot Orthoses - Customised v Off-the-Shelf in Rheumatoid Arthritis].

BACKGROUND: Foot pain is common in rheumatoid arthritis and appears to persist despite modern day medical management. Several clinical practice guidelines currently recommend the use of foot orthoses for the treatment of foot pain in people with rheumatoid arthritis. However, an evidence gap currently exists concerning the comparative clinical- and cost-effectiveness of prefabricated and customised foot orthoses in people with early rheumatoid arthritis. Early intervention with orthotics may offer the best opportunity for positive therapeutic outcomes. The primary aim of this study is to evaluate the comparative clinical- and cost-effectiveness of prefabricated versus customised orthoses for reducing foot pain over 12 months. METHODS/DESIGN: This is a multi-centre two-arm parallel randomised controlled trial comparing prefabricated versus customised orthoses in participants with early rheumatoid arthritis (< 2 years disease duration). A total of 160 (a minimum of 80 randomised to each arm) eligible participants will be recruited from United Kingdom National Health Service Rheumatology Outpatient Clinics. The primary outcome will be foot pain measured via the Foot Function Index pain subscale at 12 months. Secondary outcomes will include foot related impairments and disability via the Foot Impact Scale for rheumatoid arthritis, global functional status via the Stanford Health Assessment Questionnaire, foot disease activity via the Rheumatoid Arthritis Foot Disease Activity Index, and health-related quality of life at baseline, 6 and 12 months. Process outcomes will include recruitment/retention rates, data completion rates, intervention adherence rates, and participant intervention and trial participation satisfaction. Cost-utility and cost-effectiveness analyses will be undertaken. DISCUSSION: Outcome measures collected at baseline, 6 and 12 months will be used to evaluate the comparative clinical- and cost- effectiveness of customised versus prefabricated orthoses for this treatment of early rheumatoid arthritis foot conditions. This trial will help to guide orthotic prescription recommendations for the management of foot pain for people with early rheumatoid arthritis in future. TRIAL REGISTRATION: ISRCTN13654421. Registered 09 February 2016.

Embracing additive manufacture: implications for foot and ankle orthosis design.

BACKGROUND: The design of foot and ankle orthoses is currently limited by the methods used to fabricate the devices, particularly in terms of geometric freedom and potential to include innovative new features. Additive manufacturing (AM) technologies, where objects are constructed via a series of sub-millimetre layers of a substrate material, may present the opportunity to overcome these limitations and allow novel devices to be produced that are highly personalised for the individual, both in terms of fit and functionality.Two novel devices, a foot orthosis (FO) designed to include adjustable elements to relieve pressure at the metatarsal heads, and an ankle foot orthosis (AFO) designed to have adjustable stiffness levels in the sagittal plane, were developed and fabricated using AM. The devices were then tested on a healthy participant to determine if the intended biomechanical modes of action were achieved. RESULTS: The adjustable, pressure relieving FO was found to be able to significantly reduce pressure under the targeted metatarsal heads. The AFO was shown to have distinct effects on ankle kinematics which could be varied by adjusting the stiffness level of the device. CONCLUSIONS: The results presented here demonstrate the potential design freedom made available by AM, and suggest that it may allow novel personalised orthotic devices to be produced which are beyond the current state of the art.

Computer-aided design of customized foot orthoses: reproducibility and effect of method used to obtain foot shape.

OBJECTIVE: To determine, for a number of techniques used to obtain foot shape based around plaster casting, foam box impressions, and 3-dimensional scanning, (1) the effect the technique has on the overall reproducibility of custom foot orthoses (FOs) in terms of inter- and intracaster reliability and (2) the reproducibility of FO design by using computer-aided design (CAD) software in terms of inter- and intra-CAD operator reliability for all these techniques. DESIGN: Cross-sectional study. SETTING: University laboratory. PARTICIPANTS: Convenience sample of individuals (N=22) with noncavus foot types. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Parameters of the FO design (length, width at forefoot, width at rearfoot, and peak medial arch height), the forefoot to rearfoot angle of the foot shape, and overall volume match between device designs. RESULTS: For intra- and intercaster reliability of the different methods of obtaining the foot shape, all methods fell below the reproducibility quality threshold for the medial arch height of the device, and volume matching was <80% for all methods. The more experienced CAD operator was able to achieve excellent reliability (intraclass correlation coefficients >0.75) for all variables with the exception of forefoot to rearfoot angle, with overall volume matches of >87% of the devices. CONCLUSIONS: None of the techniques for obtaining foot shape met all the criteria for excellent reproducibility, with the peak arch height being particularly variable. Additional variability is added at the CAD stage of the FO design process, although with adequate operator experience good to excellent reproducibility may be achieved at this stage. Taking only basic linear or angular measurement parameters from the device may fail to fully capture the variability in FO design.

A clinically applicable six-segmented foot model.

We describe a multi-segmented foot model comprising lower leg, rearfoot, midfoot, lateral forefoot, medial forefoot, and hallux for routine use in a clinical setting. The Ghent Foot Model describes the kinematic patterns of functional units of the foot, especially the midfoot, to investigate patient populations where midfoot deformation or dysfunction is an important feature, for example, rheumatoid arthritis patients. Data were obtained from surface markers by a 6 camera motion capture system at 500 Hz. Ten healthy subjects walked barefoot along a 12 m walkway at self-selected speed. Joint angles (rearfoot to shank, midfoot to rearfoot, lateral and medial forefoot to midfoot, and hallux to medial forefoot) in the sagittal, frontal, and transverse plane are reported according to anatomically based reference frames. These angles were calculated and reported during the foot rollover phases in stance, detected by synchronized plantar pressure measurements. Repeated measurements of each subject revealed low intra-subject variability, varying between 0.7° and 2.3° for the minimum values, between 0.5° and 2.1° for the maximum values, and between 0.8° and 5.8° for the ROM. The described movement patterns were repeatable and consistent with biomechanical and clinical knowledge. As such, the Ghent Foot model permits intersegment, in vivo motion measurement of the foot, which is crucial for both clinical and research applications.

Generation of subject-specific, dynamic, multisegment ankle and foot models to improve orthotic design: a feasibility study.

BACKGROUND: Currently, custom foot and ankle orthosis prescription and design tend to be based on traditional techniques, which can result in devices which vary greatly between clinicians and repeat prescription. The use of computational models of the foot may give further insight in the biomechanical effects of these devices and allow a more standardised approach to be taken to their design, however due to the complexity of the foot the models must be highly detailed and dynamic. METHODS/DESIGN: Functional and anatomical datasets will be collected in a multicentre study from 10 healthy participants and 15 patients requiring orthotic devices. The patient group will include individuals with metarsalgia, flexible flat foot and drop foot.Each participant will undergo a clinical foot function assessment, 3D surface scans of the foot under different loading conditions, and detailed gait analysis including kinematic, kinetic, muscle activity and plantar pressure measurements in both barefoot and shod conditions. Following this each participant will undergo computed tomography (CT) imaging of their foot and ankle under a range of loads and positions while plantar pressures are recorded. A further subgroup of participants will undergo magnetic resonance imaging (MRI) of the foot and ankle.Imaging data will be segmented to derive the geometry of the bones and the orientation of the joint axes. Insertion points of muscles and ligaments will be determined from the MRI and CT-scans and soft tissue material properties computed from the loaded CT data in combination with the plantar pressure measurements. Gait analysis data will be used to drive the models and in combination with the 3D surface scans for scaling purposes. Predicted plantar pressures and muscle activation patterns predicted from the models will be compared to determine the validity of the models. DISCUSSION: This protocol will lead to the generation of unique datasets which will be used to develop linked inverse dynamic and forward dynamic biomechanical foot models. These models may be beneficial in predicting the effect of and thus improving the efficacy of orthotic devices for the foot and ankle.

Protocol for the Foot in Juvenile Idiopathic Arthritis trial (FiJIA): a randomised controlled trial of an integrated foot care programme for foot problems in JIA.

BACKGROUND: Foot and ankle problems are a common but relatively neglected manifestation of juvenile idiopathic arthritis. Studies of medical and non-medical interventions have shown that clinical outcome measures can be improved. However existing data has been drawn from small non-randomised clinical studies of single interventions that appear to under-represent the adult population suffering from juvenile idiopathic arthritis. To date, no evidence of combined therapies or integrated care for juvenile idiopathic arthritis patients with foot and ankle problems exists. METHODS/DESIGN: An exploratory phase II non-pharmacological randomised controlled trial where patients including young children, adolescents and adults with juvenile idiopathic arthritis and associated foot/ankle problems will be randomised to receive integrated podiatric care via a new foot care programme, or to receive standard podiatry care. Sixty patients (30 in each arm) including children, adolescents and adults diagnosed with juvenile idiopathic arthritis who satisfy the inclusion and exclusion criteria will be recruited from 2 outpatient centres of paediatric and adult rheumatology respectively. Participants will be randomised by process of minimisation using the Minim software package. The primary outcome measure is the foot related impairment measured by the Juvenile Arthritis Disability Index questionnaire's impairment domain at 6 and 12 months, with secondary outcomes including disease activity score, foot deformity score, active/limited foot joint counts, spatio-temporal and plantar-pressure gait parameters, health related quality of life and semi-quantitative ultrasonography score for inflammatory foot lesions. The new foot care programme will comprise rapid assessment and investigation, targeted treatment, with detailed outcome assessment and follow-up at minimum intervals of 3 months. Data will be collected at baseline, 6 months and 12 months from baseline. Intention to treat data analysis will be conducted.A full health economic evaluation will be conducted alongside the trial and will evaluate the cost effectiveness of the intervention. This will consider the cost per improvement in Juvenile Arthritis Disability Index, and cost per quality adjusted life year gained. In addition, a discrete choice experiment will elicit willingness to pay values and a cost benefit analysis will also be undertaken. TRIAL REGISTRATION NUMBER: UKCRN5045.

A systematic review of instruments measuring foot function, foot pain, and foot-related disability in patients with rheumatoid arthritis.

OBJECTIVE: To compose an inventory of instruments that have been described to measure foot function (i.e., pressure and/or gait parameters), foot pain, and foot-related disability in rheumatoid arthritis (RA), and to investigate the clinimetric quality of these measures. METHODS: A systematic search was conducted in Medline, CINAHL, EMBase, and Sportdiscus. Standardized criteria, extended with levels of evidence, were applied to assess the quality of the clinimetric studies and the properties (i.e., reliability, validity, and responsiveness) of the described instruments. RESULTS: A variety of measurement instruments were identified. Only 16 instruments have been studied for their measurement properties in RA patients: 7 for assessing foot function, 3 for measuring foot-related disability, and 6 for measuring both foot pain and foot-related disability. Thirteen instruments were rated for reliability, of which 10 were rated positively on different levels of evidence. No positive rating for absolute measurement error was applicable for any of the tests. Internal consistency was reported for 7 instruments; 3 assigned a positive rating. For 2 instruments, Rasch analysis was used to assess the methodologic quality. A positive rating was reported for goodness-of-fit only, not for item calibration. Seven instruments were rated for construct validity, and 3 assigned a positive rating. Only 2 instruments were rated positively for responsiveness. CONCLUSION: This review offers a basis for choosing the most appropriate instruments for measuring foot function, foot pain, and foot-related disability in RA patients, both for clinical practice and for research. Further research on the quality of these measures is urgently needed.

The validity and reliability of PressureStat for measuring plantar foot pressures in patients with rheumatoid arthritis.

BACKGROUND: Plantar pressure measurements are a useful screening tool to assess foot function and identify patients at risk of developing ulceration. The validity and reliability of PressureStat for measuring plantar pressures in patients with rheumatoid arthritis has not been addressed. METHODS: Bench testing placed the PressureStat under loads throughout the range reported for PressureStat (0-15.0 kg/cm(2)). The outputs were digitised to measure pixel density in comparison with the PressureStat calibration card. In clinical testing, simultaneous barefoot plantar pressure measurements were recorded from 10 rheumatoid arthritis patients using the PressureStat and EMED-ST systems. Reliability was examined by four independent examiners using kappa statistics. The absolute peak pressure values in each mask region were determined from the EMED-ST platform by masking in the same manner using a real size plantar pressure printout. FINDINGS: In all test conditions, the pixel density recorded from the PressureStat outputs exceeded the range recorded on the calibration card, with the largest difference in the lower ranges. In clinical testing, correcting the PressureStat scores for 'background noise' (not suggested by manufacturer) inverted and improved these comparisons. Inter-observer kappa values between the first and second readings ranged from 0.26 to 0.59, with some evidence of a learning effect. Intra-observer kappa values were 0.57, 0.51, 0.33 and 0.43 for observers 1-4 respectively. INTERPRETATION: Pressure data obtained with the PressureStat system in bench testing and patients with RA is inaccurate, particularly in the lower ranges. The grading of PressureStat readings taken from rheumatoid arthritis patients found fair to moderate intra and inter-observer agreement suggesting that interpretation is also imprecise.