Non-surgical interventions for treating osteoarthritis of the big toe joint.

BACKGROUND: Osteoarthritis (OA) affecting the first metatarsophalangeal joint (hallux rigidus) is common and painful. Several non-surgical treatments have been proposed; however, few have been adequately evaluated. Since the original 2010 review, several studies have been published necessitating this update. OBJECTIVES: To determine the benefits and harms of non-surgical treatments for big toe OA. SEARCH METHODS: We used standard, extensive Cochrane search methods. The latest search was February 2023. SELECTION CRITERIA: We included randomised trials that compared any type of non-surgical treatment versus placebo (or sham), no treatment (such as wait-and-see) or other treatment. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. The major outcomes were pain, function, quality of life, radiographic joint structure, adverse events and withdrawals due to adverse events. The primary time point was 12 weeks. We used GRADE to assess the certainty of evidence. MAIN RESULTS: This update includes six trials (547 participants). The mean age of participants ranged from 32 to 62 years. Trial durations ranged from 4 to 52 weeks. Treatments were compared in single trials as follows: arch-contouring foot orthoses versus sham inserts; shoe-stiffening inserts versus sham inserts; intra-articular injection of hyaluronic acid versus saline (placebo) injection; arch-contouring foot orthoses versus rocker-sole footwear; peloid therapy versus paraffin therapy; and sesamoid mobilisation, flexor hallucis longus strengthening and gait training plus physical therapy versus physical therapy alone. Certainty of the evidence was limited by the risk of bias and imprecision. Meta-analysis was not performed due to the heterogeneity of interventions. We reported numerical data for the 12-week time point for the three trials that used a placebo/sham control group. Arch-contouring foot orthoses versus sham inserts One trial (88 participants) showed that arch-contouring foot orthoses probably lead to little or no difference in pain, function, or quality of life compared to sham inserts (moderate certainty). Mean pain (0-10 scale, 0 no pain) with sham inserts was 3.9 points compared to 3.5 points with arch-contouring foot orthoses; a difference of 0.4 points better (95% (CI) 0.5 worse to 1.3 better). Mean function (0-100 scale, 100 best function) with sham inserts was 73.3 points compared to 65.5 points with arch-contouring foot orthoses; a difference of 7.8 points worse (95% CI 17.8 worse to 2.2 better). Mean quality of life (-0.04-100 scale, 100 best score) with sham inserts was 0.8 points compared to 0.8 points with arch-contouring foot orthoses group (95% CI 0.1 worse to 0.1 better). Arch-contouring foot orthoses may show little or no difference in adverse events and withdrawal due to adverse events compared to sham inserts (low certainty). Adverse events (mostly foot pain) were reported in 6 out of 41 people with sham inserts and 4 out of 47 people with arch-contouring foot orthoses (RR 0.58, 95% CI 0.18 to 1.92). Withdrawals due to adverse events were reported in 0 out of 41 people with sham inserts and 1 out of 47 people with arch-contouring foot orthoses (Peto OR 6.58, 95% CI 0.13 to 331). Shoe-stiffening inserts versus sham inserts One trial (100 participants) showed that shoe-stiffening inserts probably lead to little or no difference in pain, function, or quality of life when compared to sham inserts (moderate certainty). Mean pain (0-100 scale, 0 no pain) with sham inserts was 63.8 points compared to 70.1 points with shoe-stiffening inserts; a difference of 6.3 points better (95% CI 0.5 worse to 13.1 better). Mean function (0-100 scale, 100 best function) with sham inserts was 81.0 points compared to 84.9 points with shoe-stiffening inserts; a difference of 3.9 points better (95% CI 3.3 worse to 11.1 better). Mean quality of life (0-100 scale, 100 best score) with sham inserts was 53.2 points compared to 53.3 points with shoe-stiffening inserts; a difference of 0.1 points better (95% CI 3.7 worse to 3.9 better). Shoe-stiffening inserts may show little or no difference in adverse events and withdrawal due to adverse events, compared to sham inserts (low certainty). Adverse events (mostly foot pain, blisters, and spine/hip pain) were reported in 31 out of 51 people with sham inserts and 29 out of 49 people with shoe-stiffening inserts (RR 0.94, 95% CI 0.42 to 2.08). Withdrawals due to adverse events were reported in 1 out of 51 people with sham inserts and 2 out of 49 people with shoe-stiffening inserts (Peto OR 2.08, 95% CI 0.19 to 22.23). Hyaluronic acid versus placebo One trial (151 participants) showed that a single intra-articular injection of hyaluronic acid probably leads to little or no difference in pain or function compared to placebo (moderate certainty). Mean pain (0-100 scale, 0 no pain) with placebo was 72.5 points compared to 68.2 points with hyaluronic acid; a difference of 4.3 points better (95% CI 2.1 worse to 10.7 better). Mean function (0-100 scale, 100 best function) was 83.4 points with placebo compared to 85.0 points with hyaluronic acid; a difference of 1.6 points better (95% CI 4.6 worse to 7.8 better). Hyaluronic acid may provide little or no difference in quality of life (0-100 scale, 100 best score) which was 79.9 points with placebo compared to 82.9 points with hyaluronic acid; a difference of 3.0 better (95% CI 1.4 worse to 7.4 better; low certainty). There may be fewer adverse events with hyaluronic acid compared to placebo. Adverse events (mostly pain at the injection site) were reported in 43 out of 76 people with placebo compared with 27 out of 75 people with hyaluronic acid (RR 0.64, 95% CI 0.44 to 0.91; low certainty). No participants withdrew from either group due to adverse events. The effects on radiographic joint structure were not reported in any study. AUTHORS' CONCLUSIONS: The existing evidence regarding the benefits and harms of non-surgical treatments for big toe OA is limited. There is moderate-certainty evidence, based upon three single placebo/sham-controlled trials, that there are no clinically important benefits of arch-contouring foot orthoses, shoe-stiffening inserts, or a single intra-articular injection of hyaluronic acid. Further placebo-controlled trials are needed to evaluate the effectiveness of non-surgical treatments for big toe OA.

Structural Foot Characteristics in People With Midfoot Osteoarthritis: Cross-Sectional Findings From the Clinical Assessment Study of the Foot.

OBJECTIVE: This study compared radiographic measures of foot structure between people with and without symptomatic radiographic midfoot osteoarthritis (OA). METHODS: This was a cross-sectional study of adults aged 50 years and older registered with four UK general practices who reported foot pain in the past year. Bilateral weightbearing dorsoplantar and lateral radiographs were obtained. Symptomatic radiographic midfoot OA was defined as midfoot pain in the last 4 weeks, combined with radiographic OA in one or more midfoot joints (first cuneometatarsal, second cuneometatarsal, navicular-first cuneiform, and talonavicular). Midfoot OA cases were matched 1:1 for sex and age to controls with a 5-year age tolerance. Eleven radiographic measures were extracted and compared between the groups using independent sample t-tests and effect sizes (Cohen's d). RESULTS: We identified 63 midfoot OA cases (mean ± SD age was 66.8 ± 8.0 years, with 32 male and 31 female participants) and matched these to 63 controls (mean ± SD age was 65.9 ± 7.8 years). There were no differences in metatarsal lengths between the groups. However, those with midfoot OA had a higher calcaneal-first metatarsal angle (d = 0.43, small effect size, P = 0.018) and lower calcaneal inclination angle (d = 0.46, small effect size, P = 0.011) compared with controls. CONCLUSIONS: People with midfoot OA have a flatter foot posture compared with controls. Although caution is required when inferring causation from cross-sectional data, these findings are consistent with a pathomechanical pathway linking foot structure to the development of midfoot OA. Prospective studies are required to determine the temporal relationships between foot structure, function, and the development of this common and disabling condition.

Plantar pressures in people with midfoot osteoarthritis: cross-sectional findings from the Clinical Assessment Study of the Foot.

BACKGROUND: Midfoot osteoarthritis (OA) is a common condition, however its aetiology is not well understood. Understanding how plantar pressures differ between people with and without midfoot OA may provide insight into the aetiology and how best to manage this condition. RESEARCH QUESTION: To compare plantar pressures between people with and without symptomatic radiographic midfoot OA. METHODS: This was a cross-sectional study of adults aged ≥ 50 years registered with four UK general practices who reported foot pain in the past year. Symptomatic radiographic midfoot OA was defined as midfoot pain in the last four weeks, combined with radiographic OA in one or more midfoot joints. Cases were matched 1:1 for sex and age ( ± 5 years) to controls. Peak plantar pressure and maximum force in 10 regions of the foot were determined using a pressure platform (RSscan International, Olen, Belgium) and compared between the groups using independent samples t-tests and effect sizes (Cohen's d). RESULTS: We included 61 midfoot OA cases (mean age 67.0, SD 8.1, 31 males, 30 females) and matched these to 61 controls (mean age 66.0, SD 7.9). Midfoot OA cases displayed greater force (d=0.79, medium effect size, p = <0.001) and pressure at the midfoot (d=0.70, medium effect size, p = <0.001), greater force at the fourth metatarsophalangeal (MTP) joint (d=0.28, small effect size, p = 0.13), and fifth MTP joint (d=0.37, small effect size, p = 0.10) and greater pressure at the fifth MTP joint (d=0.34, small effect size, p = 0.13). They also displayed lower force (d=0.40, small effect size, p = 0.02) and pressure at the hallux (d=0.50, medium effect size, p = <0.001) and lower force (d=0.54, medium effect size, p = <0.001) and pressure at the lesser toes (d=0.48, small effect size, p = <0.001) compared with controls. SIGNIFICANCE: Midfoot OA appears to be associated with lowering of the medial longitudinal arch, greater lateral push off and less propulsion at toe off. Longitudinal studies are needed to establish causal relationships.

Efficacy of non-surgical interventions for midfoot osteoarthritis: a systematic review.

This systematic review aims to investigate the efficacy of non-surgical interventions for midfoot osteoarthritis (OA). Key databases and trial registries were searched from inception to 23 February 2023. All trials investigating non-surgical interventions for midfoot OA were included. Quality assessment was performed using the National Institutes of Health Quality Assessment Tool. Outcomes were pain, function, health-related quality of life, and adverse events. Effects (mean differences, standardised mean differences, risk ratios) were calculated where possible for the short (0 to 12 weeks), medium (> 12 to 52 weeks), and long (> 52 weeks) term. Six trials (231 participants) were included (one feasibility trial and five case series) - all were judged to be of poor methodological quality. Two trials reported arch contouring foot orthoses to exert no-to-large effects on pain in the short and medium term, and small-to-very-large effects on function in the short and medium term. Two trials reported shoe stiffening inserts to exert medium-to-huge effects on pain in the short term, and small effects on function in the short term. Two trials of image-guided intra-articular corticosteroid injections reported favourable effects on pain in the short term, small effects on pain and function in the medium term, and minimal long term effects. Two trials reported minor adverse events, and none reported health-related quality of life outcomes. The current evidence suggests that arch contouring foot orthoses, shoe stiffening inserts and corticosteroid injections may be effective for midfoot OA. Rigorous randomised trials are required to evaluate the efficacy of non-surgical interventions for midfoot OA.