The effect of good and poor walking shoe characteristics on plantar pressure and gait in people with gout

Cutaneous Calcified Mass of Foot in Pseudohypoparathyoidism: Case Report

Soft tissue calcifications frequently appear on imaging studies, representing a prevalent but non-specific discovery, varying from a local reaction without clear cause to suggesting an underlying systemic condition. Because calcifications like these can arise from various causes, an accurate differential diagnosis is crucial. Differential diagnosis entails a methodical assessment of the patient, encompassing clinical presentation, medical history, radiological and pathological findings, and other pertinent factors. Through scrutiny of the patient's medical and trauma history, we can refine potential causes of calcification to vascular, metabolic, autoimmune, neoplastic, or traumatic origins. Furthermore, routine laboratory assessments, including serum levels of calcium, phosphorus, ionized calcium, vitamin D metabolites, and parathyroid hormone (PTH), aid in identifying metabolic etiologies. We describe a rare occurrence of osteoma cutis in a 15-year-old female patient with a history of pseudohypoparathyroidism (PHP) and Albright's hereditary osteodystrophy (AHO). The patient presented with a painful mass on the lateral side of her left foot. The diagnosis was based on medical history, laboratory tests, and imaging, leading to an excisional biopsy and complete pain relief post-surgery. Understanding such rare occurrences and related conditions is crucial for accurate diagnosis and management.

Developing a core outcome set for foot and ankle disorders in rheumatic and musculoskeletal diseases: A scoping review and report from the OMERACT 2022 foot and ankle special interest group session

OBJECTIVES

Foot and ankle involvement is common in rheumatic and musculoskeletal diseases, yet high-quality evidence assessing the effectiveness of treatments for these disorders is lacking. The Outcome Measures in Rheumatology (OMERACT) Foot and Ankle Working Group is developing a core outcome set for use in clinical trials and longitudinal observational studies in this area.

METHODS

A scoping review was performed to identify outcome domains in the existing literature. Clinical trials and observational studies comparing pharmacological, conservative or surgical interventions involving adult participants with any foot or ankle disorder in the following rheumatic and musculoskeletal diseases (RMDs) were eligible for inclusion: rheumatoid arthritis (RA), osteoarthritis (OA), spondyloarthropathies, crystal arthropathies and connective tissue diseases. Outcome domains were categorised according to the OMERACT Filter 2.1.

RESULTS

Outcome domains were extracted from 150 eligible studies. Most studies included participants with foot/ankle OA (63% of studies) or foot/ankle involvement in RA (29% of studies). Foot/ankle pain was the outcome domain most commonly measured (78% of studies), being the most frequently specified outcome domain across all RMDs. There was considerable heterogeneity in the other outcome domains measured, across core areas of manifestations (signs, symptoms, biomarkers), life impact, and societal/resource use. The group's progress to date, including findings from the scoping review, was presented and discussed during a virtual OMERACT Special Interest Group (SIG) in October 2022. During this meeting, feedback was sought amongst delegates regarding the scope of the core outcome set, and feedback was received on the next steps of the project, including focus group and Delphi methods.

CONCLUSION

Findings from the scoping review and feedback from the SIG will contribute to the development of a core outcome set for foot and ankle disorders in RMDs. The next steps are to determine which outcome domains are important to patients, followed by a Delphi exercise with key stakeholders to prioritise outcome domains.

Effects of worn and new footwear on plantar pressure in people with gout

Background

In clinical trials, good quality athletic shoes offer short-term improvements (two-months) in foot pain and disability in people with gout, but these improvements are not sustained over time. This may be due to wear and subsequent changes to the structural integrity of the shoe. The aim of this study was to examine the effects of wear on plantar pressures and footwear characteristics in shoes over six-months in people with gout.

Methods

Forty people with gout participated in a cross-sectional repeated measures study. Participants wore a pair of commercially available athletic footwear for six-months. Participants then attended a study visit where the worn footwear was compared with a new pair of the same model and size of footwear. Wear characteristics (upper, midsole, outsole) and plantar pressure were measured in the two footwear conditions. Wear characteristics were analysed using paired t-tests and Fisher’s exact tests. Plantar pressure data were analysed using linear mixed models.

Results

Increases in medial midsole (P < 0.001), lateral midsole (P < 0.001) and heel midsole (P < 0.001) hardness were observed in the worn shoes. Normal upper wear patterns (P < 0.001) and outsole wear patterns (P < 0.001) were observed in most of the worn shoes. No differences in peak plantar pressures (P < 0.007) were observed between the two footwear conditions. Reduced pressure time integrals at the first metatarsophalangeal joint (P < 0.001), second metatarsophalangeal joint (P < 0.001) and hallux (P = 0.003) were seen in the worn shoes.

Conclusions

The study found signs of wear were observed at the upper, midsole and outsole in the worn footwear after six-months. These changes to the structural properties of the footwear may affect forefoot loading patterns in people with gout.

Gouty Involvement of Foot and Ankle: Beyond Flares

The foot and ankle are common locations of deposition of monosodium urate (MSU) crystals, as indicated by the clinical manifestations presented by patients with gout, which are not limited to the acute inflammation of the big toe. We present a narrative literature review aimed to update the gout involvement of foot and ankle and how it affects the quality of life. Cumulative reports indicate that gout, even at the non-tophaceous stage, could cause pain, gait impairment and limit the mobility at lower limbs. These patients may present difficulties in some activities of daily living such as choosing footwear, thus leading to an impaired quality of life. Gout is a curable disease by dissolving MSU crystals but remains unclear how this could modify some of these foot and ankle manifestations, especially when structural damage has already occurred. Furthermore, a collaboration between rheumatologists and podiatrists seems helpful to understand, relieve these symptoms and improve the quality of life in gouty patients.

Differentiating Sitting, Standing, and Walking Through Regional Plantar Pressure Characteristics

Prolonged static weight bearing (WBR) is thought to aggravate plantar heel pain and is common in the workplace, which may put employees at greater risk of developing plantar heel pain. However, objective measures of physical activity and sedentary behaviors in the workplace are lacking, making it difficult to establish or refute the connection between work exposure and plantar heel pain. Characterizing loading patterns during common workplace postures will enhance the understanding of foot function and inform the development of new measurement tools. Plantar pressure data during periods of sitting, standing, and walking were measured in ten healthy participants using the F-Scan in-shoe measurement system (Tekscan Inc, Boston, MA). Peak and average pressure, peak and average contact area, and average pressure differential were analyzed in ten different regions of the foot. A two-way repeated measures analysis of variance (ANOVA) assessed the posture by foot region interaction for each measurement parameter; significant effects of posture by foot region were identified for all five measurement parameters. Ten foot region by measurement parameter combinations were found to significantly differentiate all three postures simultaneously; seven used pressure measures to differentiate while three used area measures. The heel, lateral midfoot (LM), and medial and central forefoot (CFF) encompassed nine of ten areas capable of differentiating all postures simultaneously. This work demonstrates that plantar pressure is a viable means to characterize and differentiate three common workplace postures. The results of this study can inform the development of measurement tools for quantifying posture duration at work.

Experience of finding footwear and factors contributing to footwear choice in people with gout: a mixed methods study using a web-based survey

Background

Gout frequently affects the foot, particularly the first metatarsophalangeal joint. People with gout commonly wear ill-fitting footwear that lacks cushioning and support, which may further contribute to foot pain and disability. Footwear with good cushioning and motion control may be an effective non-pharmacological intervention. Currently, there is limited understanding about the footwear experience in people with gout. The aim was to understand footwear characteristics, experience of finding footwear, and factors contributing to footwear choice, in people with gout.

Methods

A web-based survey of people visiting a gout education website. Participants self-reported a diagnosis of gout. The 17-item survey included questions to elicit demographic and clinical characteristics, type of footwear worn, level of difficulty finding appropriate footwear, and factors contributing to choices about footwear. A mixed quantitative and qualitative methodology was used to report survey findings.

Results

Survey respondents (n = 83) were predominately White/Caucasian (84%), male (58%), and aged between 46 and 75 years-old (73%). Thirty-nine percent were newly diagnosed (< 12 months), 43% had gout for 1–10 years, and 19% had disease over 10 years. Gout flares in the feet were reported by 77 (93%) respondents, mostly in the big toe joint (73%). Seventy-six (92%) participants completed questions about footwear. Closed-in athletic shoes (88%), sturdy walking shoes (79%), and casual closed-in slip-on shoes (63%) were most frequently worn. Orthopaedic shoes were worn least often (16%). Comfort, fit, support, and ease to put on/take off were the features most often rated as important or very important when choosing footwear. Over half the respondents (64%) reported difficulty in finding footwear. Three categories, encompassing seven subcategories, were identified from the qualitative analysis to describe experiences of footwear. Categories included difficulty finding suitable shoes; impact of shoes on activity; and preferred footwear.

Conclusions

People with gout need comfortable shoes that conform to the foot, have a wide opening, made from pliable materials with adjustable straps. The main barriers related to footwear include difficulty finding shoes that are wide enough, suitable for work and aesthetically pleasing. These findings provide clinicians with important insights into the priorities and needs of people with gout that should be considered when developing footwear interventions.

Footwear interventions for foot pain, function, impairment and disability for people with foot and ankle arthritis: A literature review

OBJECTIVE

To conduct a literature review on the effectiveness of footwear on foot pain, function, impairment and disability for people with foot and ankle arthritis.

METHODS

A search of the electronic databases Scopus, Medline, CINAHL, SportDiscus and the Cochrane Library was undertaken in September 2017. The key inclusion criteria were studies reporting on findings of footwear interventions for people with arthritis with foot pain, function, impairment and/or disability. The Quality Index Tool was used to assess the methodological quality of studies included in the qualitative synthesis. The methodological variation of the included studies was assessed to determine the suitability of meta-analysis and the grading of recommendations, assessment, development and evaluation (GRADE) system. Between and within group effect sizes were calculated using Cohen's d.

RESULTS

1440 studies were identified for screening with 11 studies included in the review. Mean (range) quality scores were 67% (39-96%). The majority of studies investigated rheumatoid arthritis (n = 7), but also included gout (n = 2), and 1st metatarsophalangeal joint osteoarthritis (n = 2). Meta-analysis and GRADE assessment were not deemed appropriated based on methodological variation. Footwear interventions included off-the-shelf footwear, therapeutic footwear and therapeutic footwear with foot orthoses. Key footwear characteristics included cushioning and a wide toe box for rheumatoid arthritis; cushioning, midsole stability and a rocker-sole for gout; and a rocker-sole for 1st metatarsophalangeal joint osteoarthritis. Between group effect sizes for outcomes ranged from 0.01 to 1.26. Footwear interventions were associated with reductions in foot pain, impairment and disability for people with rheumatoid arthritis. Between group differences were more likely to be observed in studies with shorter follow-up periods in people with rheumatoid arthritis (12 weeks). Footwear interventions improved foot pain, function and disability in people with gout and foot pain and function in 1st metatarsophalangeal joint osteoarthritis. Footwear interventions were associated with changes to plantar pressure in people with rheumatoid arthritis, gout and 1st metatarsophalangeal joint osteoarthritis and walking velocity in people with rheumatoid arthritis and gout.

CONCLUSION

Footwear interventions are associated with reductions in foot pain, impairment and disability in people with rheumatoid arthritis, improvements to foot pain, function and disability in people with gout and improvements to foot pain and function in people with 1st metatarsophalangeal joint osteoarthritis. Footwear interventions have been shown to reduce plantar pressure rheumatoid arthritis, gout and 1st metatarsophalangeal joint osteoarthritis and improve walking velocity in rheumatoid arthritis and gout.

The first metatarsophalangeal joint in gout: a systematic review and meta-analysis

Background

The aim of this review was to qualitatively synthesise studies that have investigated characteristics of the first metatarsophalangeal joint (1^st MTP) in gout and to undertake a meta-analysis to estimate the average prevalence of acute 1^st MTP arthritis across studies in people with gout.

Methods

Studies published in English were included if they involved participants who had a diagnosis of gout and presented original findings relating to the following outcome measures associated with the 1^st MTP: epidemiology; clinical features; structural and functional characteristics; and microscopic and imaging features.

Results

Forty-five studies were included in the qualitative synthesis. 1^st MTP pain was a prominent feature in people with gout. People with 1^st MTP gout reported walking- and general-disability. Structural and functional characteristics of 1^st MTP gout included hallux valgus, osteoarthritis, and restricted joint motion. Successful crystal aspiration ranged from 81 to 91 % and positive crystal identification via microscopy ranged from 83 to 93 % in patients with a history of 1^st MTP gout. Imaging features were common at the 1^st MTP including the double contour sign, tophi and erosions. Eleven studies involving 2,325 participants were included in the meta-analysis, providing an estimate of the average prevalence of acute 1^st MTP arthritis across studies of 73 % (95 % prediction interval 40–92 %; range 48–97 %; I² = 93 %).

Conclusions

1^st MTP acute arthritis is highly prevalent in people with gout and has a substantial impact on patient-reported pain and disability. Gout affects the structure and function of the 1^st MTP. Microscopic and imaging studies have demonstrated crystal deposition and joint damage at the 1^st MTP in people with gout.

Foot and ankle muscle strength in people with gout: A two-arm cross-sectional study

BACKGROUND

Foot and ankle structures are the most commonly affected in people with gout. However, the effect of gout on foot and ankle muscle strength is not well understood. The primary aim of this study was to determine whether differences exist in foot and ankle muscle strength for plantarflexion, dorsiflexion, inversion and eversion between people with gout and age- and sex-matched controls. The secondary aim was to determine whether foot and ankle muscle strength was correlated with foot pain and disability.

METHODS

Peak isokinetic concentric muscle torque was measured for ankle plantarflexion, dorsiflexion, eversion and inversion in 20 participants with gout and 20 matched controls at two testing velocities (30°/s and 120°/s) using a Biodex dynamometer. Foot pain and disability was measured using the Manchester Foot Pain and Disability Index (MFPDI).

FINDINGS

Participants with gout demonstrated reduced muscle strength at both the 30°/s and 120°/s testing velocities for plantarflexion, inversion and eversion (P<0.05). People with gout also displayed a reduced plantarflexion-to-dorsiflexion strength ratio at both 30°/s and 120°/s (P<0.05). Foot pain and disability was higher in people with gout (P<0.0001) and MFPDI scores were inversely correlated with plantarflexion and inversion muscle strength at the 30°/s testing velocity, and plantarflexion, inversion and eversion muscle strength at the 120°/s testing velocity (all P<0.05).

INTERPRETATION

People with gout have reduced foot and ankle muscle strength and experience greater foot pain and disability compared to controls. Foot and ankle strength reductions are strongly associated with increased foot pain and disability in people with gout.

Characteristics of the first metatarsophalangeal joint in gout and asymptomatic hyperuricaemia: a cross-sectional observational study

Background

This study aimed to identify patient-reported outcomes and clinician-assessed characteristics of the first metatarsophalangeal joint (1MTPJ) in people with gout and with asymptomatic hyperuricaemia by comparing them to normouricaemic controls.

Methods

Twenty four people with gout (without current symptoms of acute arthritis), 29 with asymptomatic hyperuricaemia and 34 age- and sex-matched controls participated in this cross-sectional observational study. Patient-reported outcomes included 1MTPJ pain, foot pain and disability, body pain, lower limb function, activity limitation and overall wellbeing. Clinician-assessed characteristics of the 1MTPJ included range of motion (ROM), plantar- and dorsi-flexion force, foot posture, temperature and hallux valgus severity.

Results

Compared to controls, participants with gout reported greater 1MTPJ pain (p = 0.014), greater foot pain and disability (p < 0.001), increased odds of having disabling foot pain (odds ratio (OR) 13.4, p < 0.001), decreased lower limb function for daily living (p = 0.002) and recreational (p < 0.001) activities, increased activity limitation (p = 0.002), reduced overall wellbeing (p = 0.034), reduced ROM (p < 0.001), reduced plantarflexion force (p = 0.012), increased 1MTPJ plantar (p = 0.004), dorsal (p = 0.003) and medial (p = 0.004) temperature and had increased odds of having more severe hallux valgus (OR 0.3 p = 0.041). Compared to controls, participants with asymptomatic hyperuricaemia had increased odds of having disabling foot pain (OR 4.2, p = 0.013), increased activity limitation (p = 0.033), decreased lower limb function for daily living (p = 0.026) and recreational (p = 0.010) activities, increased 1MTPJ plantarflexion force (p = 0.004) and a more pronated foot type (p = 0.036).

Conclusions

People with gout demonstrate 1MTPJ-specific changes indicative of subclinical inflammation, even in the absence of acute arthritis. People with asymptomatic hyperuricaemia, who exhibit no features or symptoms of gout, also report high levels of foot- and lower limb-related pain and disability.

Determinants of footwear difficulties in people with plantar heel pain

Background

Plantar heel pain is a common foot disorder aggravated by weight-bearing activity. Despite considerable focus on therapeutic interventions such as orthoses, there has been limited investigation of footwear-related issues in people with plantar heel pain. The aim of this study was to investigate whether people with plantar heel pain experience footwear-related difficulties compared to asymptomatic individuals, as well as identifying factors associated with footwear comfort, fit and choice.

Methods

The footwear domain of the Foot Health Status Questionnaire (FHSQ) was assessed in 192 people with plantar heel pain and 69 asymptomatic controls. The plantar heel pain group was also assessed on a variety of measures including: foot posture, foot strength and flexibility, pedobarography and pain level. A univariate analysis of covariance, with age as the covariate, was used to compare the heel pain and control groups on the FHSQ footwear domain score. A multiple regression model was then constructed to investigate factors associated with footwear scores among participants with plantar heel pain.

Results

When compared to asymptomatic participants, people with plantar heel pain reported lower FHSQ footwear domain scores (mean difference −24.4; p < 0.001; 95 % CI: −32.0 to −17.0). In the participants with heel pain, footwear scores were associated with maximum force beneath the postero-lateral heel during barefoot walking, toe flexor strength and gender.

Conclusions

People with plantar heel pain experience difficulty with footwear comfort, fit and choice. Reduced heel loading during barefoot walking, toe flexor weakness and female gender are all independently associated with reports of footwear difficulties in people with heel pain. Increased focus, in both clinical and research settings, is needed to address footwear-related issues in people with plantar heel pain.

Foot problems in people with gout in primary care: baseline findings from a prospective cohort study

Background

Foot problems are common in people with gout yet the prevalence of current foot problems in people with gout and the burden they present to healthcare systems is not known. This cross-sectional study aimed to determine the prevalence and associations of hallux valgus, foot pain and disability in people with gout, and to assess the frequency with which foot problems lead to consultation with healthcare professionals.

Methods

Adults registered with 20 general practices who had consulted their GP about gout or been prescribed allopurinol or colchicine in the preceding two years were mailed a questionnaire. Prevalence of hallux valgus, foot pain in the last month, and disabling foot pain in the mailed population were ascertained using validated instruments and estimated by inverse-weighted logistic regression. Associations with socio-demographic, comorbid and gout-specific factors were examined using logistic regression. Participants were asked if they had seen health care professionals for foot problems within the preceding 12 months.

Results

One thousand one hundred eighty-four questionnaires were received (response 66 %). Prevalence of hallux valgus was 36.3 %, foot pain in the last month 22.3 % and disabling foot pain 14.5 %. Hallux valgus associated with age (adjusted OR 1.47 per 10-year increase, 95 % CI 1.26, 1.72) and female gender (2.03; 1.31, 3.15). Foot pain in the last month associated with age (1.24; 1.00, 1.55), obesity (BMI 30.0–34.9 2.67; 1.32, 5.38; BMI ≥ 35.0 3.16; 1.44, 6.93), mild depression (2.04; 1.09, 3.81) and polyarticular gout attacks (1.86; 1.18, 2.95). Disabling foot pain associated with age (1.42; 1.08, 1.87), obesity (BMI 30.0–34.9 3.73; 1.54, 9.09; BMI ≥ 35.0 4.36; 1.64, 11.64), depression (mild 2.63; 1.25, 5.53; moderate 3.53; 1.11, 11.26) and ischaemic heart disease (2.45; 1.32, 4.53). In the previous 12 months, 495 (42.8 %) reported consulting their GP about their feet and 281 (23.7 %) a podiatrist/chiropodist.

Conclusions

Foot problems are common in people with gout and frequently lead to healthcare consultation. Hallux valgus has similar associations to those seen in the general population, whereas foot pain associates with obesity and gout characteristics, and disabling foot pain with obesity and comorbidity. Patient assessment should consider foot problems and offer specific treatment where relevant.