Current and future advances in practice: mechanical foot pain.

Mechanical foot pain affects ∽20% of the UK population >50 years of age, with ∼10% reporting disabling pain that impacts daily activities. For most people, foot pain improves over time, but for some this can become chronic and disabling, affecting physical activity, participation, mental health and work capacity. Mechanical foot pain can present as localized pain, but more often the pain presents in multiple structures. Traditional treatments for mechanical foot pain are largely based on self-management that includes pain control, reassurance of healing trajectory, and activity or footwear modifications. Randomized controlled trials support the short-term use of exercise and foot orthoses for some foot conditions; however, accessibility can be limited by regional variations in procurement compounded by a lack of long-term trials. The roles of weight loss and strengthening of the foot and leg muscles offer new avenues to explore.

A multi-professional survey of UK practice in the use of intra-articular corticosteroid injection for symptomatic first metatarsophalangeal joint osteoarthritis.

BACKGROUND: The first metatarsophalangeal joint is the most common site of osteoarthritis (OA) in the foot and ankle. Intra-articular corticosteroid injections are widely used for this condition, but little is known about their use in practice. This study explored current practice within the UK National Health Service (NHS) relating to the administration of intra-articular corticosteroids for people with painful first metatarsophalangeal joint (MTPJ) OA. METHODS: A cross-sectional survey using Qualtrics online survey platform (Qualtrics, Provo, UT, USA), distributed through professional bodies, special interest groups, and social media. RESULTS: One hundred forty-four healthcare professionals responded, including podiatrists (53/144; 39%), orthopaedic surgeons (28/144; 19%), podiatric surgeons (26/144; 17%) and physiotherapists (24/144; 16%). Half of respondents administered up to 25 corticosteroid injections per year (67/136; 49%) but some administered more than fifty (21/136; 15%). Injections were administered across the healthcare system but were most common in hospital settings (64/136; 44%) followed by community (38/136; 26%), with less delivered in primary care (11/136; 8%). Half of respondents routinely used image-guidance, either ultrasound or x-ray/fluoroscopy (65/136; 48%) although over one third used none (52/136; 38%). Imaging guidance was more common amongst medical professionals (21/31; 68%) compared to non-medical health professionals (45/105; 43%). Overall, methylprednisolone acetate was the most common corticosteroid used. Medical professionals mostly injected methylprednisolone acetate (n = 15/27; 56%) or triamcinolone acetonide (n = 11/27; 41%), whereas premixed methylprednisolone acetate with lidocaine hydrochloride was the most common preparation used by non-medical health professionals (41/85; 48%). When injecting non premixed steroid, lidocaine hydrochloride (15/35; 43%) was the most common choice of local anaesthetic for non-medical health professionals but medical professionals showed more variation between lidocaine hydrochloride (8/23; 35%) levobupivacaine hydrochloride (9/23; 39%) and bupivacaine hydrochloride (5/23; 22%). CONCLUSIONS: Multiple professional groups regularly administer intra-articular corticosteroids for symptomatic first MTPJ OA across a range of NHS healthcare settings. Overall, methylprednisolone acetate was the most commonly administered steroid and lidocaine hydrochloride the most common local anaesthetic. There was large variation in the use of imaging guidance, type and dose of steroid, local anaesthetic, and clinical pathways used in the intra-articular injection of corticosteroids for people with first MTPJ OA.

Research priority setting in UK podiatric surgery.

Evidence-based practice provides the foundation for high quality patient care, and in the NHS, research is seen as vital to enable service transformation and improve outcomes. Research is one of the four pillars of enhanced and advanced clinical practice and is therefore a fundamental part of podiatric surgery services. In order to meet the UK health research strategies, the most recent being 'Saving and Improving Lives: The Future of UK Clinical Research Delivery' (2021), the Faculty of Podiatric Surgery in the UK agreed to support the development of research priorities in order to inform a future research strategy.The Podiatric Surgery Research Strategy Group was set up and embarked on a project with the aim of engaging its members in formulating and agreeing national research priorities. The initial stage included a national research scoping survey to identify key themes, topic, and research questions. The final stage consisted of developing and enabling a live consensus vote conducted at the 2022 national Faculty of Podiatric Surgery Conference. At the end of the vote, the top five research topics that met the agreement criteria were: 1. Surgical treatment - forefoot, 2. Patient reported outcome measures, 3. Post-operative management, 4. Surgical treatment - midfoot and 5. Service delivery. The top five research questions that met the criteria were1. How does quality of life improve following elective foot surgery? 2. How does podiatric surgery benefit the health of the population? 3. How does podiatric surgery benefit the health of the population in the at-risk foot? 4. What is the most effective Lapidus fixation option? and 5. What is the benefit of utilising PASCOM-10 to improve large scale outcome data? These will inform the initial UK podiatric surgery research priorities in the next three to five years.

Intrinsic foot muscle size and associations with strength, pain and foot-related disability in people with midfoot osteoarthritis.

BACKGROUND: To compare intrinsic foot muscle size between people with and without symptomatic midfoot osteoarthritis, and examine the association between muscle size and strength, pain and foot-related disability. METHODS: Twenty-three participants with symptomatic midfoot osteoarthritis and 23 age, sex and BMI matched controls were included. Intrinsic foot muscle cross-sectional area was measured using MRI. Hand-held dynamometry was used to assess foot and ankle muscle strength, and foot-related pain and disability was measured using Manchester Foot Pain & Disability Index. FINDINGS: Small and non-statistically significant differences were found in intrinsic foot muscle cross-sectional area between the two groups (effect sizes 0.15-0.26, p > 0.05). Muscle strength was reduced in the midfoot osteoarthritis group, with differences of 12-33% (effect sizes 0.47-1.2). In the control group, moderate positive associations) existed between foot muscle cross-sectional area and lesser digits flexor strength (r = 0.5 to 0.7, p < 0.05). Conversely, in the midfoot osteoarthritis group, negligible positive associations were found (r < 0.3, p > 0.05). Associations between foot muscle cross-sectional with and pain and disability scores in the midfoot osteoarthritis group were negligible (r < -0.3, p > 0.05). INTERPRETATION: Despite reductions in maximal isometric muscle strength, midfoot osteoarthritis does not appear to be associated with reduced intrinsic foot muscle cross-sectional area measured by MRI. Muscle compositional or neural factors may explain the reductions in muscle strength and variation in symptoms in people with midfoot osteoarthritis and should be investigated.

Bone Marrow Lesions and Magnetic Resonance Imaging-Detected Structural Abnormalities in Patients With Midfoot Pain and Osteoarthritis: A Cross-Sectional Study.

OBJECTIVE: To compare magnetic resonance imaging (MRI)-detected structural abnormalities in patients with symptomatic midfoot osteoarthritis (OA), patients with persistent midfoot pain, and asymptomatic controls, and to explore the association between MRI features, pain, and foot-related disability. METHODS: One hundred seven adults consisting of 50 patients with symptomatic and radiographically confirmed midfoot OA, 22 adults with persistent midfoot pain but absence of radiographic OA, and 35 asymptomatic adults underwent 3T MRI of the midfoot and clinical assessment. MRIs were read for the presence and severity of abnormalities (bone marrow lesions [BMLs], subchondral cysts, osteophytes, joint space narrowing [JSN], effusion-synovitis, tenosynovitis, and enthesopathy) using the Foot Osteoarthritis MRI Score. Pain and foot-related disability were assessed with the Manchester Foot Pain and Disability Index. RESULTS: The severity sum score of BMLs in the midfoot was greater in patients with midfoot pain and no signs of OA on radiography compared to controls (P = 0.007), with a pattern of involvement in the cuneiform-metatarsal joints similar to that in patients with midfoot OA. In univariable models, BMLs (ρ = 0.307), JSN (ρ = 0.423), and subchondral cysts (ρ = 0.302) were positively associated with pain (P < 0.01). In multivariable models, MRI abnormalities were not associated with pain and disability when adjusted for covariates. CONCLUSION: In individuals with persistent midfoot pain but no signs of OA on radiography, MRI findings suggested an underrecognized prevalence of OA, particularly in the second and third cuneiform-metatarsal joints, where BML patterns were consistent with previously recognized sites of elevated mechanical loading. Joint abnormalities were not strongly associated with pain or foot-related disability.

Foot and Leg Muscle Weakness in People With Midfoot Osteoarthritis.

OBJECTIVE: To compare foot and leg muscle strength in people with symptomatic midfoot osteoarthritis (OA) with asymptomatic controls, and to determine the association between muscle strength, foot pain, and disability. METHODS: Participants with symptomatic midfoot OA and asymptomatic controls were recruited for this cross-sectional study from general practices and community health clinics. The maximum isometric muscle strength of the ankle plantarflexors, dorsiflexors, invertors and evertors, and the hallux and lesser toe plantarflexors was measured using hand-held dynamometry. Self-reported foot pain and foot-related disability were assessed with the Manchester Foot Pain and Disability Index. Differences in muscle strength were compared between groups. Multivariable regression was used to determine the association between muscle strength, foot pain, and disability after adjusting for covariates. RESULTS: People with midfoot OA (n = 52) exhibited strength deficits in all muscle groups, ranging from 19% (dorsiflexors) to 30% (invertors) relative to the control group (n = 36), with effect sizes of 0.6-1.1 (P < 0.001). In those with midfoot OA, ankle invertor muscle strength was negatively and independently associated with foot pain (ß = -0.026 [95% confidence interval (95% CI) -0.051, -0.001]; P = 0.045). Invertor muscle strength was negatively associated with foot-related disability, although not after adjustment for depressive symptoms (ß = -0.023 [95% CI -0.063, 0.017]; P = 0.250). CONCLUSION: People with symptomatic midfoot OA demonstrate weakness in the foot and leg muscles compared to asymptomatic controls. Preliminary indications from this study suggest that strengthening of the foot and leg muscles may offer potential to reduce pain and improve function in people with midfoot OA.

Development and Reliability of a Preliminary Foot Osteoarthritis Magnetic Resonance Imaging Score.

OBJECTIVE: Foot osteoarthritis (OA) is very common but underinvestigated musculoskeletal condition and there is little consensus as to common magnetic resonance imaging (MRI) features. The aim of this study was to develop a preliminary foot OA MRI score (FOAMRIS) and evaluate its reliability. METHODS: This preliminary semiquantitative score included the hindfoot, midfoot, and metatarsophalangeal joints. Joints were scored for joint space narrowing (JSN; 0-3), osteophytes (0-3), joint effusion/synovitis, and bone cysts (present/absent). Erosions and bone marrow lesions (BML) were scored (0-3) and BML were evaluated adjacent to entheses and at sub-tendon sites (present/absent). Additionally, tenosynovitis (0-3) and midfoot ligament pathology (present/absent) were scored. Reliability was evaluated in 15 people with foot pain and MRI-detected OA using 3.0T MRI multi-sequence protocols, and assessed using ICC as an overall score and per anatomical site. RESULTS: Intrareader agreement (ICC) was generally good to excellent across the foot in joint features (JSN 0.90, osteophytes 0.90, effusion/synovitis 0.46, cysts 0.87), bone features (BML 0.83, erosion 0.66, BML entheses 0.66, BML sub-tendon 0.60) and soft tissue features (tenosynovitis 0.83, ligaments 0.77). Interreader agreement was lower for joint features (JSN 0.43, osteophytes 0.27, effusion/synovitis 0.02, cysts 0.48), bone features (BML 0.68, erosion 0.00, BML entheses 0.34, BML sub-tendon 0.13), and soft tissue features (tenosynovitis 0.35, ligaments 0.33). CONCLUSION: This preliminary FOAMRIS demonstrated good intrareader reliability and fair interreader reliability when assessing the total feature scores. Further development is required in cohorts with a range of pathologies and to assess the psychometric measurement properties.

Comparability of off the shelf foot orthoses in the redistribution of forces in midfoot osteoarthritis patients.

BACKGROUND: Midfoot osteoarthritis (OA) is more prevalent and strongly associated with pain than previously thought. Excessive mechanical loading of the midfoot structures may contribute to midfoot OA and studies suggest that functional foot orthoses (FFO) may relieve pain through improving function. This exploratory study aimed to evaluate the mechanical effect of two off-the-shelf FFOs, compared to a sham orthosis in people with midfoot OA. METHODS: Thirty-three participants with radiographically confirmed symptomatic midfoot OA were randomly assigned to wear either a commercially available FFO or a sham orthosis. After wearing their assigned orthoses for 12 weeks, plantar pressure measurements were obtained under shoe-only and assigned orthoses conditions. Participants assigned to the sham, were additionally tested wearing a second type of FFO at the end of trial. Descriptive mean change (±95% confidence intervals) in plantar pressure for each orthoses condition, versus a shoe only baseline condition are presented. FINDINGS: Compared to the shoe only conditions, both FFOs decreased hindfoot and forefoot maximum force and peak pressure, whilst increasing maximum force and contact area under the midfoot. The sham orthosis yielded plantar pressures similar to the shoe-only condition. INTERPRETATION: Findings suggest that both types of off-the-shelf FFO may provide mechanical benefit, whilst the sham orthoses produced similar findings to the shoe only condition, indicating appropriate sham properties. This paper provides insight into the mechanisms of action underpinning the use of FFOs and sham orthoses, which can inform future definitive RCTs examining the effect of orthoses on midfoot OA.

Foot orthoses in the treatment of symptomatic midfoot osteoarthritis using clinical and biomechanical outcomes: a randomised feasibility study.

This randomised feasibility study aimed to examine the clinical and biomechanical effects of functional foot orthoses (FFOs) in the treatment of midfoot osteoarthritis (OA) and the feasibility of conducting a full randomised controlled trial. Participants with painful, radiographically confirmed midfoot OA were recruited and randomised to receive either FFOs or a sham control orthosis. Feasibility measures included recruitment and attrition rates, practicality of blinding and adherence rates. Clinical outcome measures were: change from baseline to 12 weeks for severity of pain (numerical rating scale), foot function (Manchester Foot Pain and Disability Index) and patient global impression of change scale. To investigate the biomechanical effect of foot orthoses, in-shoe foot kinematics and plantar pressures were evaluated at 12 weeks. Of the 119 participants screened, 37 were randomised and 33 completed the study (FFO = 18, sham = 15). Compliance with foot orthoses and blinding of the intervention was achieved in three quarters of the group. Both groups reported improvements in pain, function and global impression of change; the FFO group reporting greater improvements compared to the sham group. The biomechanical outcomes indicated the FFO group inverted the hindfoot and increased midfoot maximum plantar force compared to the sham group. The present findings suggest FFOs worn over 12 weeks may provide detectable clinical and biomechanical benefits compared to sham orthoses. This feasibility study provides useful clinical, biomechanical and statistical information for the design and implementation of a definitive randomised controlled trial to evaluate the effectiveness of FFOs in treating painful midfoot OA.

Effectiveness of neuromuscular taping on pronated foot posture and walking plantar pressures in amateur runners.

OBJECTIVES: To determine the effect kinesiotaping (KT) versus sham kinesiotaping (sham KT) in the repositioning of pronated feet after a short running. DESIGN: Prospective, randomised, double-blinded, using a repeated-measures design with no cross-over. METHODS: 116 amateur runners were screened by assessing the post-run (45min duration) foot posture to identify pronated foot types (defined by Foot Posture Index [FPI] score of ≥6). Seventy-three runners met the inclusion criteria and were allocated into two treatment groups, KT (n=49) and sham KT (n=24). After applying either the KT or sham KT and completing 45min of running (mean speed of 12km/h), outcome measures were collected (FPI and walking Pedobarography). RESULTS: FPI was reduced in both groups, more so in the KT group (mean FPI between group difference=0.9, CI 0.1-1.9), with a score closer to neutral. There were statistically significant differences between KT and sham KT (p<.05 and p<.01) in pressure time integral, suggesting that sham KT had a greater effect. CONCLUSIONS: KT may be of some assistant to clinicians in correction of pronated foot posture in a short-term. There was no effect of KT, however on pressure variables at heel strike or toe-off following a short duration of running, the sham KT technique had a greater effect. LEVEL OF EVIDENCE: Therapy, level 1b.

Ligament and bone pathologic abnormalities more frequent in neuropathic joint disease in comparison with degenerative arthritis of the foot and ankle: implications for understanding rapidly progressive joint degeneration.

OBJECTIVE: The variable disease progression of osteoarthritis (OA) and the basis for rapid joint deterioration in some subgroups of patients are poorly understood. To explore an anatomic basis for rapidly progressive OA, this observational study compared the magnetic resonance imaging (MRI) patterns of disease between patients with neuropathic joint disease (NJD) and patients with degenerative arthritis of the ankle and foot. METHODS: MR images of the foot and ankle of patients with early NJD (n = 7) and patients with OA (n = 15) were assessed. The anonomized MR images were dichotomously scored by a musculoskeletal radiologist for the presence of the following abnormalities per bone (of a total of 14 bones): cartilage defects, bone cysts, bone marrow edema, fractures, joint debris, joint effusions, tendinopathy, tendinitis, and ligament tears. RESULTS: Although the degree of cartilage damage and joint cyst formation was comparable between the groups, the degree of ligament tears, or change in MRI signal intensity in the ligaments, was significantly greater in patients with NJD compared with patients with OA (median of 3 tears versus 0, of 14 total bones; P < 0.01). Moreover, in patients with early NJD compared with patients with OA, there was a significantly greater degree of diffuse bone marrow edema (median of 6.5 tarsal bones versus 2 adjacent bones, of 14 total bones; P < 0.01), a greater number of bone fractures (median 4 versus 0; P < 0.01), and more frequent bone debris (median 4.5 versus 0; P = 0.013). CONCLUSION: This analysis of NJD in the foot and ankle shows the predominance of bone and ligament abnormalities in NJD compared with the pattern of involvement in OA. These findings highlight the importance of structures other than articular cartilage in OA of the ankle and foot, and suggest that rapid joint degeneration in NJD may be more ligamentogenic or osteogenic in nature.

Weight-bearing passive dorsiflexion of the hallux in standing is not related to hallux dorsiflexion during walking.

STUDY DESIGN: Case control study. OBJECTIVE: To explore the validity of the assumptions underpinning the Hubscher maneuver of hallux dorsiflexion in relaxed standing, by comparing the relationship between static and dynamic first metatarsophalangeal (MTP) joint motions in groups differentiated by normal and abnormal clinical test findings. BACKGROUND: Limitation of motion at the first MTP joint during gait may be due to either structural or functional factors. Functional hallux limitus (FHL) has been proposed as a term to describe the situation in which the first MTP joint shows no limitation when non-weight bearing, but shows limited dorsiflexion during gait. One clinical test of first MTP joint limitation during standing (the Hubscher maneuver or Jack's test) has become widely used in physical therapy, orthopedic, and podiatric assessments, supposedly to assess for the presence of hallux limitations during gait. The utility of the test is based on an assumption that restriction during the static maneuver is predictive of functional limitation at this joint during gait. Despite a lack of evidence for the validity of such an assumption, the outcome of the static test is often used to infer risk of overuse injury or as an outcome for functional therapy. This paper examines the validity of the assumptions supporting this widely used static test. METHODS AND MEASURES: First-MTP-joint motion was assessed using an electromagnetic motion tracking system in cases (n = 15) demonstrating clinically limited passive hallux dorsiflexion in relaxed standing, and in 15 controls matched for age and gender and demonstrating a clinically normal Hubscher maneuver. Maximum hallux dorsiflexion was measured with the subject non-weight bearing (seated), during relaxed standing, and during normal walking. RESULTS: Hallux dorsiflexion was similar in cases and controls when motions were measured non-weight bearing (cases mean +/- SD, 55.0 degrees +/- 11.0 degrees; controls mean + SD, 55.0 degrees +/- 10.7 degrees), confirming the absence of structural joint change. In relaxed standing, maximum dorsiflexion was 50% less in cases (mean +/- SD, 19.0 degrees +/- 8.9 degrees) than in the controls (mean +/- SD, 39.4 degrees +/- 6.1 degrees; P < .001), supporting the initial test outcome and confirming the visual test observation of static functional limitation in the case group. During gait, however, cases (mean +/- SD, 36.4 degrees +/- 9.1 degrees), and controls (mean +/- SD, 36.9 degrees +/- 7.9 degrees) demonstrated comparable maximum dorsiflexion (P = .902). There was no significant relationship between static and dynamic first MTP joint motions (r = 0.186, P = .325). CONCLUSION: The clinical test of limited passive hallux dorsiflexion in stance is a valid test only of hallux dorsiflexion available during relaxed standing. There is no association between maximum dorsiflexion observed during a static weight-bearing examination and that occurring at the same joint during walking.

The relationship between hallux dorsiflexion and ankle joint complex frontal plane kinematics: a preliminary study.

BACKGROUND: It has been suggested that the function of the first metatarsophalangeal joint may be related to the motion of the ankle joint complex. OBJECTIVE: This study explored the relationship between ankle joint complex and first metatarsophalangeal joint motion during gait in a group of 14 who demonstrated clinically limited passive hallux dorsiflexion in quiet standing (cases), and 15 matched controls. METHOD: An electromagnetic tracking system was used to measure the ankle joint complex frontal plane motion and first metatarsophalangeal joint sagittal plane motion during gait, in both cases and controls. The case group was then evaluated further to investigate the effect of an orthosis on first metatarsophalangeal joint motion. FINDINGS: The correlation between maximum ankle joint complex eversion and maximum first metatarsophalangeal joint dorsiflexion during gait was r=0.471. Within the case group, maximum rearfoot eversion was reduced following the application of the orthoses, but there was no change in sagittal first metatarsophalangeal joint rotations. INTERPRETATION: The relationship between maximum ankle joint complex eversion and first metatarsophalangeal joint dorsiflexion kinematics found in this study was moderate, and decreasing maximum ankle joint complex eversion with an orthosis did not result in any increase in first metatarsophalangeal joint dorsiflexion during gait in patients with functional first metatarsophalangeal joint limitation. These results do not support the assumption that ankle joint complex eversion influences first metatarsophalangeal joint motion substantially.