Centre of pressure characteristics during walking in individuals with and without first metatarsophalangeal joint osteoarthritis

Association of Bone Shape and Alignment Analyzed Using Statistical Shape Modeling With Severity of First Metatarsophalangeal Joint Osteoarthritis

OBJECTIVE

We aimed to explore the relationship between bone shape and radiographic severity in individuals with first metatarsophalangeal joint osteoarthritis (first MTP joint OA).

METHODS

Weightbearing lateral and dorsoplantar radiographs were obtained for the symptomatic foot of 185 participants (105 females, aged 22 to 85 years) with clinically diagnosed first MTP joint OA. Participants were classified into none/mild, moderate, or severe categories using a standardized atlas. An 80-point model for lateral radiographs and 77-point model for dorsoplantar radiographs was used to define independent modes of variation using statistical shape modeling software. Odds ratios adjusted for confounders were calculated using ordinal regression to determine the association between radiographic severity and mode scores.

RESULTS

After assessment and grading of radiographs, 35 participants (18.9%) were included in the none/mild first MTP joint OA severity category, 69 (37.2%) in the moderate severity category, and 81 (43.7%) in the severe category. For lateral-view radiographs, 16 modes of variation were included, which collectively represented 83.2% of total shape variance. Of these, four modes were associated with radiographic severity. For dorsoplantar-view radiographs, 15 modes of variation were included, representing 82.6% of total shape variance. Of these, six modes were associated with radiographic severity.

CONCLUSIONS

Variations in the shape and alignment of the medial cuneiform, first metatarsal, and proximal and distal phalanx of the hallux are significantly associated with radiographic severity of first MTP joint OA. Prospective studies are required to determine whether bone shape characteristics are associated with the development and/or progression of this condition.

Time-varying and speed-matched model for the evaluation of stroke-induced changes in ankle mechanics

The ankle mechanics (stiffness and moment) are modulated continuously when interacting with the environment during human walking. However, it remains unclear how ankle mechanics vary with walking speeds, and how they are affected by stroke. This study aimed to determine time-varying ankle stiffness and moment in stroke participants during walking, comparing them with healthy participants at matched speeds. A motion capture system, surface electromyography (EMG) system and force plates were used to measure biomechanics of seven healthy participants walking at 5 controlled speeds and ten patients with stroke at self-selected speeds. The ankle moment and stiffness during the stance phase were calculated using an EMG-driven musculoskeletal model. Surface equations of ankle moment and stiffness in healthy participants, with walking speed and stance phase as variables, were proposed based on polynomial fitting. Results showed that as walking speed increased, there was an increase in the ankle stiffness and moment of healthy participants during 77 %-89 % and 63 %-91 % of stance phase, respectively. Patients with stroke had lower ankle stiffness and moment at self-selected walking speed than healthy participants at 1.04 m/s walking speed during 52 %-87 % and 52 %-91 % of stance phase, respectively. At matched walking speed, the peak values of ankle stiffness and moment in patients with stroke were significantly less than those in healthy participants (p = 0.007; p = 0.028, respectively). This study proposes a novel approach to evaluate the ankle mechanics of patients with stroke using the speed-matched model of healthy participants and may provide insights into understanding speed-dependent movement mechanisms of human walking.

Three-dimensional gait analysis of orthopaedic common foot and ankle joint diseases

Walking is an indispensable mode of transportation for human survival. Gait is a characteristic of walking. In the clinic, patients with different diseases exhibit different gait characteristics. Gait analysis describes the specific situation of human gait abnormalities by observing and studying the kinematics and dynamics of limbs and joints during human walking and depicting the corresponding geometric curves and values. In foot and ankle diseases, gait analysis can evaluate the degree and nature of gait abnormalities in patients and provide an important basis for the diagnosis of patients' diseases, the correction of abnormal gait and related treatment methods. This article reviews the relevant literature, expounds on the clinical consensus on gait, and summarizes the gait characteristics of patients with common ankle and foot diseases. Starting from the gait characteristics of individuals with different diseases, we hope to provide support and reference for the diagnosis, treatment and rehabilitation of clinically related diseases.

Assessment and indicators of hallux limitus related with quality of life and foot health in school children

Background

Functional Hallux Limitus (FHL) is a dynamic foot dysfunction characterized by a limitation of hallux dorsiflexion when the first metatarsal head is under load. FHL plays a role in the development of osteoarthrosis in the first metatarsophalangeal joint (IMTPJ). Forefoot disorders can significantly impact an individual's quality of life, leading to dysfunction and pain. The aim of this project was to evaluate the quality of life of school-aged individuals with and without FHL using the Foot Health Status Questionnaire (FHSQ).

Methods

A case-control study was conducted to evaluate the outcomes in paediatric age. A total sample of 116 children between 6 and 12 years old was used to conduct this research. The sample was divided into two groups: (i) the healthy group (n = 58) and the FHL group (n = 58). The FHSQ was completed and the FHL test was performed in a seated position to classify the patients into the selected group.

Results

Non-significant changes were observed when the mean values of the FHSQ domains were compared between the groups with and without FHL, except for the "general foot health" domain (p = 0,024) associated with the specific foot health section (section 1) of the Questionnaire. For the domains linked with the general well-being section (section 2), there was not a statistically difference in the mean of the scores obtained between the two school-aged groups with and without FHL, being slightly lower in the group with the presence of FHL for the overall health and physical function domains. Both the healthy and case groups obtained and identical range of scores (10-100) for the "foot pain" domain. Nevertheless, the mean of the score was lower for the participants with FHL.

Conclusions

The perception of the quality of general foot health was poorer in the school-aged group with FHL. Variables such as foot pain and footwear are likely contributors influencing the perception of foot health quality. The school-aged population with FHL faces a decline in the quality of foot life. Ensuring adequate foot control in children and implementing future foot programs for this population are imperative for enhancing school children's perception of foot health and managing the development of pain and footwear-related issues.

Neuropathic Pain Associated With First Metatarsophalangeal Joint Osteoarthritis: Frequency and Associated Factors

OBJECTIVE

To determine whether neuropathic pain is a feature of first metatarsophalangeal (MTP) joint osteoarthritis (OA).

METHODS

A total of 98 participants (mean ± SD age 57.4 ± 10.3 years) with symptomatic radiographic first MTP joint OA completed the PainDETECT questionnaire (PD-Q), which has 9 questions regarding the intensity and quality of pain. The likelihood of neuropathic pain was determined using established PD-Q cutoff points. Participants with unlikely neuropathic pain were then compared to those with possible/likely neuropathic pain in relation to age, sex, general health (Short Form 12 [SF-12] health survey), psychological well-being (Depression, Anxiety and Stress Scale), pain characteristics (self-efficacy, duration, and severity), foot health (Foot Health Status Questionnaire [FHSQ]), first MTP dorsiflexion range of motion, and radiographic severity. Effect sizes (Cohen's d coefficient) were also calculated.

RESULTS

A total of 30 (31%) participants had possible/likely neuropathic pain (19 possible [19.4%], 11 likely [11.2%]). The most common neuropathic symptoms were sensitivity to pressure (56%), sudden pain attacks/electric shocks (36%) and burning (24%). Compared to those with unlikely neuropathic pain, those with possible/likely neuropathic pain were significantly older (d = 0.59, P = 0.010), had worse SF-12 physical scores (d = 1.10, P < 0.001), pain self-efficacy scores (d = 0.98, P < 0.001), FHSQ pain scores (d = 0.98, P < 0.001), and FHSQ function scores (d = 0.82, P < 0.001), and had higher pain severity at rest (d = 1.01, P < 0.001).

CONCLUSION

A significant proportion of individuals with first MTP joint OA report symptoms suggestive of neuropathic pain, which may partly explain the suboptimal responses to commonly used treatments for this condition. Screening for neuropathic pain may be useful in the selection of targeted interventions and may improve clinical outcomes.

Hallux Limitus Influence on Plantar Pressure Variations during the Gait Cycle: A Case-Control Study

BACKGROUND

Hallux limitus is a common foot disorder whose incidence has increased in the school-age population. Hallux limitus is characterized by musculoskeletal alteration that involves the metatarsophalangeal joint causing structural disorders in different anatomical areas of the locomotor system, affecting gait patterns. The aim of this study was to analyze dynamic plantar pressures in a school-aged population both with functional hallux and without.

METHODS

A full sample of 100 subjects (50 male and 50 female) 7 to 12 years old was included. The subjects were identified in two groups: the case group (50 subjects characterized as having hallux limitus, 22 male and 28 female) and control group (50 subjects characterized as not having hallux limitus, 28 male and 22 female). Measurements were obtained while subjects walked barefoot in a relaxed manner along a baropodometric platform. The hallux limitus test was realized in a seated position to sort subjects out into an established study group. The variables checked in the research were the surface area supported by each lower limb, the maximum peak pressure of each lower limb, the maximum mean pressure of each lower limb, the body weight on the hallux of each foot, the body weight on the first metatarsal head of each foot, the body weight at the second metatarsal head of each foot, the body weight at the third and fourth metatarsal head of each foot, the body weight at the head of the fifth metatarsal of each foot, the body weight at the midfoot of each foot, and the body weight at the heel of each foot.

RESULTS

Non-significant results were obtained in the variable of pressure peaks between both study groups; the highest pressures were found in the hallux with a p-value of 0.127 and in the first metatarsal head with a p-value 0.354 in subjects with hallux limitus. A non-significant result with a p-value of 0.156 was obtained at the second metatarsal head in healthy subjects. However, significant results were observed for third and fourth metatarsal head pressure in healthy subjects with a p-value of 0.031 and regarding rearfoot pressure in subjects with functional hallux limitus with a p-value of 0.023.

CONCLUSIONS

School-age subjects with hallux limitus during gait exhibit more average peak plantar pressure in the heel and less peak average plantar pressure in the third and fourth metatarsal head as compared to healthy children aged between 7 and 12 years old.

Effects of arch support doses on the center of pressure and pressure distribution of running using statistical parametric mapping

Insoles with an arch support have been used to address biomechanical risk factors of running. However, the relationship between the dose of support and running biomechanics remains unclear. The purpose of this study was to determine the effects of changing arch support doses on the center of pressure (COP) and pressure mapping using statistical parametric mapping (SPM). Nine arch support variations (3 heights * 3 widths) and a flat insole control were tested on fifteen healthy recreational runners using a 1-m Footscan pressure plate. The medial-lateral COP (COPML) coordinates and the total COP velocity (COPVtotal) were calculated throughout the entirety of stance. One-dimensional and two-dimensional SPM were performed to assess differences between the arch support and control conditions for time series of COP variables and pressure mapping at a pixel level, respectively. Two-way ANOVAs were performed to test the main effect of the arch support height and width, and their interaction on the peak values of the COPVtotal. The results showed that the COPVtotal during the forefoot contact and forefoot push off phases was increased by arch supports, while the COP medial-lateral coordinates remained unchanged. There was a dose-response effect of the arch support height on peak values of the COPVtotal, with a higher support increasing the first and third valleys but decreasing the third peak of the COPVtotal. Meanwhile, a higher arch support height shifted the peak pressure from the medial forefoot and rearfoot to the medial arch. It is concluded that changing arch support doses, primarily the height, systematically altered the COP velocities and peak plantar pressure at a pixel level during running. When assessing subtle modifications in the arch support, the COP velocity was a more sensitive variable than COP coordinates. SPM provides a high-resolution view of pressure comparisons, and is recommended for future insole/footwear investigations to better understand the underlying mechanisms and improve insole design.

International Foot and Ankle Osteoarthritis Consortium review and research agenda for diagnosis, epidemiology, burden, outcome assessment and treatment

OBJECTIVE

To summarise the available evidence relating to the diagnosis, epidemiology, burden, outcome assessment and treatment of foot and ankle osteoarthritis (OA) and to develop an agenda to guide future research.

METHOD

Members of the International Foot and Ankle Osteoarthritis Consortium compiled a narrative summary of the literature which formed the basis of an interactive discussion at the Osteoarthritis Research Society International World Congress in 2021, during which a list of 24 research agenda items were generated. Following the meeting, delegates were asked to rank the research agenda items on a 0 to 100 visual analogue rating scale (0 = not at all important to 100 = extremely important). Items scoring a mean of 70 or above were selected for inclusion.

RESULTS

Of the 45 delegates who attended the meeting, 31 contributed to the agenda item scoring. Nineteen research agenda items met the required threshold: three related to diagnosis, four to epidemiology, four to burden, three to outcome assessment and five to treatment.

CONCLUSIONS

Key knowledge gaps related to foot and ankle OA were identified, and a comprehensive agenda to guide future research planning was developed. Implementation of this agenda will assist in improving the understanding and clinical management of this common and disabling, yet relatively overlooked condition.

Development of the center of pressure velocity in the healing process after intra-articular calcaneus fractures

BACKGROUND

Calcaneal fractures are among the most common foot injuries and sometimes develop manifold post-surgical complications. Restricted foot movement is one of the main functional limitations which often persists during long-term rehabilitation. Therefore, it is important to quantitatively monitor the biomechanical foot mobility after calcaneal fracture from an early stage in order to achieve an optimal therapeutic treatment.

RESEARCH QUESTION

Evaluation of the Center of Pressure velocity (v_COP) in patients after intrarticular calcaneal fractures during the healing progress from three to 24 months after surgery.

METHODS

A total of 20 patients with unilateral calcaneal fracture were investigated by means of pedobarography and marker-based gait analysis at three, six, 12 and 24 months after surgery. Data for v_COP [m/s], maximum external dorsal extension moments during stance (DEmoment_stance) and tibiotalar range of motion during mid stance (MS) and terminal stance (TS) were obtained. Functional evaluation was performed using clinical examination (e.g. calf circumference measurements) and patient-reported outcome measures (SF-36).

RESULTS

When compared to the healthy side, v_COP of the injured side showed a significant reduction during MS (3 months: 48%, p < 0.001; 6 months: 13%; p = 0.040) and an significant increase during TS (3 months: 110%, p < 0.001; 6 months: 43%, p < 0.001; 12 months: 17%, p = 0.012). DEmoment_stance of the fractured foot, showed a significant increase of 80% (p < 0.001) from three to 24 months after surgery, which correlated with v_COP at three and six months after surgery (p < 0.05; v_{COP MS:} 3 months: r = 0.876, 6 months: r = 0.685; v_{COP TS:} 3 months: r = -0.554, 6 months r = -0.626).

SIGNIFICANCE

v_COP might serve as an indicator for foot mobility and function during the early healing phase after calcaneal fractures. As v_COP can be obtained by pedobarography it is more readily accessible an less costly compared to foot function obtained by marker based gait analysis.

Postural Control Differences between Patients with Posterior Tibial Tendon Dysfunction and Healthy People during Gait

BACKGROUND

Patients with posterior tibial tendon dysfunction (PTTD) may exhibit postural instability during walking likely due to a loss of medial longitudinal arch, abnormal foot alignment, and pain. While many studies have investigated gait alterations in PTTD, there is no understanding of dynamic postural control mechanisms in this population during gait, which will help guide rehabilitation and gait training programs for patients with PTTD. The purpose of the study was to assess dynamic postural control mechanisms in patients with stage II PTTD as compared to age and gender matched healthy controls.

METHODS

Eleven patients with stage II PTTD (4 males and 7 females; age 59 ± 1 years; height 1.66 ± 0.12 m; mass 84.2 ± 16.0 kg) and ten gender and age matched controls were recruited in this study. Participants were asked to walk along a 10 m walkway. Ten Vicon cameras and four AMTI force platforms were used to collect kinematic and center of pressure (COP) data while participants performed gait. To test differences between PTTD vs. control groups, independent t-tests (set at α < 0.05) were performed.

RESULTS

Patients with PTTD had significantly higher double stance ratio (+23%) and anterior-posterior (AP) time to contact (TTC) percentage (+16%) as compared to healthy control. However, PTTD had lower AP COP excursion (-19%), AP COP velocity (-30%), and medial-lateral (ML) COP velocity (-40%) as compared to healthy controls. Mean ML COP trace values for PTTD were significantly decreased (-23%) as compared to controls, indicating COP trace for PTTD tends to be closer to the medial boundary than controls during single-support phase of walking.

CONCLUSION

PTTD patients showed more conservative and cautious postural strategies which may help maintain balance and reduce the need for postural adjustment during PTTD gait. They also showed more medially shifted COP patterns than healthy controls during single-support phase of walking. Dynamic postural control outcomes could be used to develop effective gait training programs aimed at alleviating a medial shift of COP (everted foot) for individuals with PTTD in order to improve their functionality and gait efficiency.

The effect of ankle osteoarthritis and total ankle arthroplasty on center of pressure position

Total ankle arthroplasty (TAA) is a common surgical approach for patients with end-stage ankle osteoarthritis (OA). However, very little is known about the path of the center of pressure (COP) of the foot, and thus important aspects of load transfer, muscle mechanical advantage, and balance, in patients before or after surgery. The objective of this study was to trace the pathway of the COP under the foot in patients with symptomatic ankle OA, comparing asymmetry between affected and unaffected limbs. From force plate data, proximodistal and mediolateral positions of the COP beneath the foot were calculated and compared for the affected and unaffected foot in patients with unilateral ankle OA (N = 93) before and after TAA. Gender and age at surgery had little or no effect in this study. Patients with ankle OA had minimal COP position asymmetry before surgery, and this asymmetry was reduced following surgery. Before surgery, patients had a slower walking speed and a shorter path of the COP which began relatively distal to the heel and ended relatively proximal to the hallux. TAA increased the proximodistal distance the COP traveled under both the unaffected and affected foot, a pattern that was maintained for over 2-year postsurgery. TAA allows patients with ankle OA to maintain a longer COP path than they had before surgery on both sides that is closer to that reported for unaffected individuals, extending effectively from the heel to the hallux, potentially improving pedal mechanics.

Assessment of Selected Spatio-Temporal Gait Parameters on Subjects with Pronated Foot Posture on the Basis of Measurements Using OptoGait. A Case-Control Study

Walking is part of daily life and in asymptomatic subjects it is relatively easy. The physiology of walking is complex and when this complex control system fails, the risk of falls increases. As a result, gait disorders have a major impact on the older adult population and have increased in frequency as a result of population aging. Therefore, the OptoGait sensor is intended to identify gait imbalances in pronating feet to try to prevent falling and injury by compensating for it with treatments that normalize such alteration. This study is intended to assess whether spatiotemporal alterations occur in the gait cycle in a young pronating population (cases) compared to a control group (non-pronating patients) analyzed with OptoGait. Method: a total of n = 142 participants consisting of n = 70 cases (pronators) and n = 72 healthy controls were studied by means of a 30 s treadmill program with a system of 96 OptoGait LED sensors. Results: Significant differences were found between the two groups and both feet in stride length and stride time, gait cycle duration and gait cadence (in all cases p < 0.05). Conclusions: pronating foot posture alters normal gait patterns measured by OptoGait; this finding presents imbalance in gait as an underlying factor. Prevention of this alteration could be considered in relation to its relationship to the risk of falling in future investigations.

Foot orthoses for first metatarsophalangeal joint osteoarthritis: study protocol for the FORT randomised controlled trial

Background

First metatarsophalangeal (MTP) joint osteoarthritis (OA) is a painful and debilitating condition affecting nearly one in 10 people aged over 50 years. Non-drug, non-surgical treatments are recommended by OA clinical guidelines, yet there have only ever been two randomised controlled trials (RCTs) evaluating such strategies in people with first MTP joint OA. Foot orthoses are a common non-drug, non-surgical strategy used by allied health professionals for people with first MTP joint OA, however, it is unknown whether these devices are effective in improving the symptoms associated with the condition. This clinical trial aimed to determine whether contoured foot orthoses lead to greater reductions in first MTP joint pain on walking compared to sham flat insoles in people with first MTP joint OA.

Methods

The FORT trial (Foot ORthoses for big Toe joint osteoarthritis) is a two-arm participant- and assessor-blinded, multi-site RCT conducted in Melbourne, Sydney, Brisbane and the Gold Coast, Australia. We are recruiting 88 community-dwelling people with symptomatic radiographic first MTP joint OA. Following baseline assessment, participants are randomized to receive either: i) contoured foot orthoses; or ii) sham flat insoles following baseline assessment. Participants have two visits with a study podiatrist where they are provided with their allocated insoles, to be worn daily for 12 weeks at all times when wearing shoes. The primary outcome is self-reported first MTP joint pain on walking (numerical rating scale), assessed at baseline and 12 weeks. Secondary outcomes include additional measures of first MTP joint and foot pain, physical function, quality of life, participant-perceived global ratings of change (pain and function), and level of physical activity.

Discussion

This study will provide novel evidence about whether contoured foot orthoses improve pain and other symptoms compared to sham insoles in people with first MTP joint OA. Outcomes will help to inform clinical guidelines and practice about the use of foot orthoses for managing symptoms in this under-researched group of people with OA.

Trial registration

Prospectively registered with the Australian New Zealand Clinical Trials Registry (reference: ACTRN12619000926134) on 3/07/2019.

Lifetime occupation is not associated with radiographic osteoarthritis of the first metatarsophalangeal joint in a cohort study of UK women

OBJECTIVE

The study aim was to determine whether lifetime occupation was associated with the presence of radiographic osteoarthritis (ROA) of the first metatarsophalangeal joint (MTPJ) in women.

METHOD

Data were collected from the prospective, population-based Chingford 1000 Women study. This cohort of women, aged 45-64 years at inception, was established in 1989 from a single general practice in Chingford, UK. Data has subsequently been collected repeatedly. Data from baseline, year six and year ten was used for the purposes of this cross-sectional study. The primary outcome was the presence of dorsal view ROA of the first MTPJ. The main exposure was lifetime occupation, categorised according to levels of occupation previously defined via international consensus: 1. Sedentary, 2. Light, 3. Light manual, 4. Heavy manual. Logistic regression analyses were conducted to quantify the relationship between lifetime occupation type and the presence of ROA of the first MTPJ, adjusting for age, body mass index and lifetime high-heeled footwear use as potential interactive variables for each decade.

RESULTS

Data for 209 women were included within this study. The mean (SD) age was 57 (±5.2) years. Predominant lifetime occupation was reported as sedentary by 51.7%, as light by 0%, as light manual by 33.5% and as heavy manual by 14.8% of participants. There were no statistical associations between lifetime occupation type and the presence of ROA of the first MTPJ in either the unadjusted (OR = 0.99, CI = 0.78-1.26,P = 0.96) partially adjusted (for age and BMI; OR = 1.00, CI = 0.78-1.29, P = 0.99) or fully adjusted models (for age, BMI and lifetime high heel footwear use for each decade of working life (OR = 1.02, CI = 0.79-1.31, P = 0.91); high-heel footwear use up to 20s (OR = 0.83, CI = 0.71-1.31, P = 0.83); high-heel footwear use in 20-30s (OR = 1.00, CI = 0.75-1.3, P = 0.98); high-heel footwear use in 30-40s (OR = 1.00, CI = 0.70-1.42, P = 0.99); high-heel footwear use in 40-50s (OR = 0.90, CI = 0.58-1.40, P = 0.65); high-heel footwear use in 50s (OR = 0.63,CI = 0.36-1.09, P = 0.10).

CONCLUSIONS

The findings suggest that lifetime occupation is not associated with the presence of ROA of the fist metatarsophalangeal joint. There does not appear to be any interactive effect between lifetime occupation, lifetime high-heel footwear use, age or BMI and ROA of the first MTPJ. In later life a positive trend towards increased ROA in those who reported lifetime high-heel footwear use was noted and this may be worthy of further research.

First metatarsophalangeal joint range of motion is associated with lower limb kinematics in individuals with first metatarsophalangeal joint osteoarthritis

Background

Osteoarthritis of the first metatarsophalangeal joint (1st MTP joint OA) is a common and disabling condition that results in pain and limited joint range of motion. There is inconsistent evidence regarding the relationship between clinical measurement of 1st MTP joint maximum dorsiflexion and dynamic function of the joint during level walking. Therefore, the aim of this study was to examine the association between passive non-weightbearing (NWB) 1st MTP joint maximum dorsiflexion and sagittal plane kinematics in individuals with radiographically confirmed 1st MTP joint OA.

Methods

Forty-eight individuals with radiographically confirmed 1st MTP joint OA (24 males and 24 females; mean age 57.8 years, standard deviation 10.5) underwent clinical measurement of passive NWB 1st MTP joint maximum dorsiflexion and gait analysis during level walking using a 10-camera infrared Vicon motion analysis system. Sagittal plane kinematics of the 1st MTP, ankle, knee, and hip joints were calculated. Associations between passive NWB 1st MTP joint maximum dorsiflexion and kinematic variables were explored using Pearson’s r correlation coefficients.

Results

Passive NWB 1st MTP joint maximum dorsiflexion was significantly associated with maximum 1st MTPJ dorsiflexion (r = 0.486, p < 0.001), ankle joint maximum plantarflexion (r = 0.383, p = 0.007), and ankle joint excursion (r = 0.399, p = 0.005) during gait. There were no significant associations between passive NWB 1st MTP joint maximum dorsiflexion and sagittal plane kinematics of the knee or hip joints.

Conclusions

These findings suggest that clinical measurement of 1st MTP joint maximum dorsiflexion provides useful insights into the dynamic function of the foot and ankle during the propulsive phase of gait in this population.

Structural Characteristics Associated With Radiographic Severity of First Metatarsophalangeal Joint Osteoarthritis

OBJECTIVE

To determine whether foot structure varies according to the presence and radiographic severity of first metatarsophalangeal (MTP) joint osteoarthritis (OA).

METHODS

Weight-bearing dorsiplantar and lateral radiographs were obtained for the symptomatic foot of 185 participants (105 women, ages 22-85 years) with clinically diagnosed first MTP joint OA. A validated atlas was used to classify participants as having radiographic first MTP joint OA and to stratify into 3 categories of severity (none/mild, moderate, severe). Bone length and width and angular measures of the forefoot and medial arch were performed on radiographs, and differences between categories were compared using univariate general linear models, adjusting for confounders.

RESULTS

A total of 150 participants were categorized as having radiographic first MTP joint OA, and participants were further stratified into none/mild (n = 35), moderate (n = 69), or severe (n = 81) OA categories. Participants with radiographically defined first MTP joint OA displayed a greater hallux abductus interphalangeal angle. Greater radiographic severity of first MTP joint OA was associated with a larger hallux abductus interphalangeal angle, a wider first metatarsal and proximal phalanx, and a smaller intermetatarsal angle. No differences in medial arch measurements were observed between the categories.

CONCLUSION

First ray alignment and morphology differed according to the presence and severity of first MTP joint OA. Prospective studies are required to determine whether the observed differences are a cause or consequence of OA.