Radiographic evaluation of foot osteoarthritis: sensitivity of radiographic variables and relationship to symptoms

Risk Factors for Midfoot Arthritis Associated With Medical History by Weight Bearing Computed Tomography

Tarso-metatarsal joints and naviculocuneiform joints comprising midfoot is the second most commonly involved joints following the first metatarsophalangeal joint in the foot. However, related factors of midfoot arthritis (MA) have been rarely reported. The bony structure and alignment can be more precisely assessed using Weight-Bearing Computed Tomography (WBCT) than conventional radiographs. Therefore, the aim of this study was to investigate risk factors for MA related to medical history and comorbid foot deformities using WBCT. WBCT data from September 2014 to April 2022 were extracted from a single referral hospital. All cases were divided into two groups by the presence of MA. Twenty-five potential related factors including demographics, etiology, and common co-occurring foot deformities were collected for comparison. Six hundred six cases (247 males and 359 females) among consecutive 1316 cases between September 2014 to April 2022 were selected. One hundred thirty-nine male cases (56.3%) and 210 female cases (58.5%) showed MA. In stepwise multiple logistic regression analysis, 5 factors remained statistically significant. The multivariate-adjusted odds ratios for age, laterality, body mass index (BMI), Progressive Collapsing Foot Deformity (PCFD), and lesser toe deformities (LTD) were 1.08, 1.54, 1.05, 6.62, and 3.03 respectively. Risk factors for MA associated with medical history and foot deformities included age, laterality, BMI, PCFD, and LDT.

Outcomes of Tibiotalocalcaneal Arthrodesis vs Talar Body Prosthesis as Treatment of Collapsed Avascular Necrosis of the Talus: A 10- to 13-Year-Follow-up Retrospective Comparative Study

BACKGROUND

Joint salvage surgeries such as tibiotalocalcaneal arthrodesis and talar prosthesis are commonly used in the surgical treatment of collapsed avascular necrosis of the talus (AVNT). However, differences in outcomes of these 2 surgical treatments are still inconclusive. This study compared the 10- to 13-year outcomes and 10-year survivorship rates of tibiotalocalcaneal arthrodesis and talar body prosthesis in the surgical treatment of collapsed AVNT.

METHODS

A retrospective comparative study was conducted of patients who underwent either tibiotalocalcaneal arthrodesis or talar body prosthesis implantation between 2005 and 2012. The demographic matching process resulted in 24 patients per treatment group. Clinical outcomes were evaluated using a numeric rating scale (NRS) of 2 hours of activities of daily living (ADL) and Foot and Ankle Ability Measure (FAAM) for ADL. Radiographic assessments included the incidence of nonunion, adjacent joint arthritis, and prosthesis loosening. The 10-year survivorship of both surgical treatments was calculated. A P value of less than .05 was considered statistically significant.

RESULTS

The median NRS of 2 hours of ADL and FAAM score for ADL were statistically significantly better in the talar body prosthesis group, with P values of .001 and <.001, respectively. The statistically significant differences in FAAM score for ADL exceeded the minimum clinically important difference. In the tibiotalocalcaneal arthrodesis group, nonunion was observed in 7 of 24 patients (29.2%). No prosthesis loosening was reported in the talar body prosthesis group. The 10-year survivorship was statistically significantly higher in talar body prosthesis than tibiotalocalcaneal arthrodesis (95.8% vs 70.8%), P = .023.

CONCLUSION

Talar body prosthesis implantation in selected eligible patients demonstrated statistically significantly better 10- to 13-year clinical outcomes and higher 10-year survivorship compared with tibiotalocalcaneal arthrodesis in the surgical treatment of collapsed AVNT.

LEVEL OF EVIDENCE

Level III, retrospective cohort comparative study.

Prevalence of midfoot arthritis and lesser toe deformities

BACKGROUND

The aim of this study was to investigate the epidemiology of Midfoot Arthritis (MA) and Lesser toe deformity (LTD) using Weight-Bearing Computed Tomography (WBCT).

METHODS

606 cases (247 male, 359 female) among 1316 consecutive cases with WBCT data from September 2014 to April 2022 were retrospectively reviewed at a single referral institution. The Cochran-Armitage test was performed to evaluate the trend of prevalence with respect to age group and obesity classification.

RESULTS

139 male (56.3%) and 210 female cases (58.5%) showed MA. 157 male (63.6%) and 222 female cases (61.6%) showed LTD. 115 male (19.0%) and 157 female cases (25.9%) showed both MA and LTD. The prevalence of MA and LTD increased with age in both genders. The incidence of MA in males showed an increasing tendency until obesity class II and then was slightly decreased in obesity class III. This is contrary to females whose prevalence increased with increasing obesity groups. LTD had a similar pattern in both genders to obesity classification.

CONCLUSIONS

The prevalence of MA and LTD increased with age and increasing obesity groups for both genders.

LEVEL OF EVIDENCE

Level III, Retrospective Comparative Study.

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.

The talar body prosthesis treated end-stage ankle arthritis with talar body deficient: a 6-13 years of follow-up outcomes and 6-year survivorship

INTRODUCTION

Talar body deficient provides a unique challenge for ankle arthritis treatment. We studied the clinical-radiographic outcomes at 6 to 13 years and 6 year prosthesis survivorship of patients treated for ankle arthritis with poor talar body bone stock using a talar body prosthesis (TBP).

MATERIALS AND METHODS

Between 2008 and 2015, we treated 32 consecutive end-stage ankle arthritis patients with talar body deficiency by TBP implantation and fascia interposition. One patient was excluded with a diagnosis of inflammatory arthritis. We assessed visual analogue scale (VAS) of ankle pain, sagittal range of motion, American Orthopaedics Foot and Ankle Society (AOFAS) ankle-hindfoot score, Foot Ankle Ability Measure (FAAM) of activity daily living (ADL), prosthesis tibiotalar surface angle, radiographic prosthesis loosening, adjacent joint arthritis and complication. Pre-operative to last follow-up outcomes (at 6-13 years) were compared. Prosthesis survivorship was analyzed at 6 year follow-up. p < 0.05 was considered a significant difference.

RESULTS

There was statistically significant improvement of median VAS ankle pain, as 8.0 (IQR 1.0) to 1.0 (IQR 2.0), AOFAS ankle-hindfoot score from 48 (IQR 21) to 80 (IQR 7.0), FAAM of ADL from50.0 (28.0) to 88.0 (IQR 15.0), and sagittal ROM from 20^o (IQR 19°) to 33° (IQR 14°), p < 0.05. The median tibiotalar surface angle was statistically significant improved from 85.0° (IQR 8.0°) to 89.0° (IQR 3.0°), p < 0.001. No radiographic prosthesis loosening or adjacent talonavicular-calcaneocuboid joint arthritis. The 6 year prosthesis survivorship was 93.5% (95% CI 84.9-100.0%). End of survivorship was observed in 2 patients due to progressive valgus tilting at 16° and 18°, respectively. No prosthesis was revised.

CONCLUSIONS

TBP implantation with fascia replacing the articular end of distal tibia provided significant better pre- to post-operative clinical outcomes and had 6 year survivorship as 93.5% for the treatment of ankle arthritis with talar body deficient.

LEVEL OF EVIDENCE

IV.

A bibliometric analysis of published research employing musculoskeletal imaging modalities to evaluate foot osteoarthritis

Objectives

Temporal and global changes in research utilising imaging to assess foot osteoarthritis is currently unknown. This study aimed to undertake a bibliometric analysis of published research to: (1) identify the imaging modalities that have been used to evaluate foot osteoarthritis; (2) explore the temporal changes and global differences in the use of these imaging modalities; and (3) to evaluate performance related to publication- and citation-based metrics.

Methods

A literature search was conducted using Scopus to identify studies which had used imaging to assess foot osteoarthritis. Extracted data included publication year, imaging modality, citations, affiliations, and author collaboration networks. Temporal trends in the use of each imaging modality were analysed. Performance analysis and science mapping were used to analyse citations and collaboration networks.

Results

158 studies were identified between 1980 and 2021. Plain radiography was the most widely used modality, followed by computed tomography, magnetic resonance imaging (MRI) and ultrasound imaging (USI), respectively. The number of published studies increased over time for each imaging modality (all P ≥ 0.018). The most productive country was the United States of America (USA), followed by the United Kingdom and Australia. International authorship collaboration was evident in 57 (36.1%) studies. The average citation rate was 23.4 per study, with an average annual citation rate of 2.1.

Conclusions

Published research employing imaging to assess foot osteoarthritis has increased substantially over the past four decades. Although plain radiography remains the gold standard modality, the emergence of MRI and USI in the past two decades continues to advance knowledge and progress research in this field.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13047-022-00549-0.

Müller-Weiss Disease: The Descriptive Factors of Failure Conservative Treatment

BACKGROUND

Conservative treatment is the first-line approach for Müller-Weiss disease (MWD). However, factors associated with the failure of conservative treatment have never been reported. Our objectives were to compare the differences in demographic and radiographic parameters between "successful" and "failure" conservative treatment in patients with MWD and identify descriptive factors associated with failure conservative treatment.

METHODS

We retrospectively reviewed 68 patients with MWD divided into 29 "failure" and 39 "successful" conservative treatment groups. Demographic characteristics, Foot and Ankle Outcome Score (FAOS), visual analog scale (VAS) scores for pain and walking disability, and radiographic parameters such as calcaneal pitch, lateral Meary, anteroposterior (AP) Meary angle, and talonavicular-naviculocuneiform arthritis were compared. Logistic regression analysis was performed to identify descriptive factors of failure conservative treatment. A P value <.05 was considered a statistically significant difference.

RESULTS

We found more severe VAS pain and walking disability scores and FAOS for the pain, activities of daily living, and quality of life subscales in the failure group (P < .05). Regression analysis demonstrated 2 significant descriptive factors associated with failure conservative treatment: abducted AP Meary angle >13.0 degrees and radiographic talonavicular arthritis. No demographic characteristics were found to be associated with failure conservative treatment.

CONCLUSION

Midfoot abduction (AP Meary angle, >13 degrees) and radiographic talonavicular arthritis were factors associated with failure conservative treatment in MWD and should be determined concurrently with the clinical severity. Classification systems for MWD should include these factors.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Identification of Radiographic Foot Osteoarthritis: Sensitivity of Views and Features Using The La Trobe Radiographic Atlas

OBJECTIVE

To compare the sensitivity of alternative case-finding approaches for the identification of foot osteoarthritis (OA) based on the La Trobe radiographic atlas.

METHODS

Cross-sectional study of 533 adults aged ≥50 years with foot pain in the past year. Weightbearing dorso-plantar (DP) and lateral x-rays were taken of both feet. The La Trobe radiographic atlas was used to document the presence of osteophytes (OP) and joint space narrowing (JSN). Prevalence of OA in each joint was documented using both views and features in combination (as recommended in the original atlas), and by using a single view (DP or lateral only) and a single feature (OP or JSN only).

RESULTS

Compared to the recommended case definition based on OP and JSN using both views, a DP only view identified between 15 and 77% of OA cases, while a lateral only view identified between 28 and 97% of OA cases. Compared to the recommended case definition of using both features, using only OP identified between 46 and 94% of OA cases, while using only JSN identified between 19 and 76% of OA cases.

CONCLUSION

Applying the La Trobe radiographic atlas but using only one x-ray view (DP or lateral) or one feature (OP or JSN) in isolation misses a substantial number of OA cases, and the sensitivity of these approaches varies considerably between different foot joints. These findings indicate that, where possible, the atlas should be administered according to the original description to avoid under-ascertainment of radiographic foot OA.

Foot Osteoarthritis Frequency and Associated Factors in a Community-Based Cross-Sectional Study of White and African American Adults

OBJECTIVE

Few studies have explored foot osteoarthritis (OA) in the general population. The purpose of this study was to determine the frequency of foot OA and identify associated factors in a cross-sectional analysis of a large community-based cohort.

METHODS

Data were from the 2013-2015 study visit of the Johnston County OA Project. Radiographic OA of the foot was defined using the La Trobe radiographic atlas (≥2 osteophytes or joint space narrowing in at least 1 of 5 joints). Symptomatic OA of the foot was defined as foot radiographic OA with pain, aching, or stiffness in the same foot. At the foot-level, separate logistic regression models with generalized estimating equations to account for intraperson correlations were performed to examine associations of foot radiographic OA or symptomatic OA with age, body mass index (BMI), sex, race, educational attainment, and previous foot injury.

RESULTS

Of 864 participants with available data (mean age 71 years, mean BMI 30 kg/m² , 68% women, 33% African American, 13% <12 years of schooling), 22% had foot radiographic OA, 20% had foot symptoms, and 5% had foot symptomatic OA. Radiographic, but not symptomatic, foot OA was more common in African American than White participants. Participants with obesity, compared to normal weight, had >2 times the odds of radiographic OA and >5 times the odds of symptomatic OA in adjusted models.

CONCLUSION

Foot radiographic OA and foot symptoms were common in the sample, but both conditions simultaneously (i.e., symptomatic OA) occurred infrequently. Notably, obesity was linked with foot symptomatic OA, perhaps implicating metabolic or mechanical influences.

Silastic first metatarsophalangeal joint arthroplasty for the treatment of end-stage hallux rigidus

AIMS

Arthroplasty for end-stage hallux rigidus (HR) is controversial. Arthrodesis remains the gold standard for surgical treatment, although is not without its complications, with rates of up to 10% for nonunion, 14% for reoperation and 10% for metatarsalgia. The aim of this study was to analyze the outcome of a double-stemmed silastic implant (Wright-Medical, Memphis, Tennessee, USA) for patients with end-stage HR.

METHODS

We conducted a retrospective review of 108 consecutive implants in 76 patients, between January 2005 and December 2016, with a minimum follow-up of two years. The mean age of the patients at the time of surgery was 61.6 years (42 to 84). There were 104 females and four males. Clinical, radiological, patient reported outcome measures (PROMS) data, a visual analogue score (VAS) for pain, and satisfaction scores were collected.

RESULTS

The survivorship at a mean follow-up of 5.3 years (2.1 to 14.1) was 97.2%. The mean Manchester Oxford Foot and Ankle Questionnaire (MOXFQ) scores improved from 78.1 to 11.0, and VAS scores for pain from 7/10 to 1.3/10. The rate of satisfaction was 90.6%. Three implants (2.8%) required revision; one for infection, one-month postoperatively, and two for stem breakage at 10.4 and 13.3 years postoperatively. There was a 1.9% reoperation rate other than revision, 23.1% of patients developed a minor complication, and 21.1% of patients had non-progressive and asymptomatic cysts on radiological review.

CONCLUSION

We report a 97.2% survivorship at a mean follow-up of 5.3 years with this implant. We did not find progressive osteolysis, as has been previously reported. These results suggest that this double-stemmed silastic implant provides a predictable and reliable alternative with comparable outcomes to arthrodesis for the treatment of end-stage HR. Cite this article: Bone Joint J 2020;102-B(2):220-226.

An Anatomic and Clinical Study of the Innervation of the Dorsal Midfoot Capsule

BACKGROUND

Dorsal pain from osteoarthritic midfoot joints is thought to be relayed by branches of the medial and lateral plantar, sural, saphenous, and deep peroneal nerves (DPN). However, there is no consensus on the actual number or pathways of the nervous branches for midfoot joint capsular innervation. This study examined the DPN's terminal branches at the midfoot joint capsules through anatomic dissection and confirmation of their significance in a clinical case series of patients with midfoot pain relief after DPN block.

METHODS

Eleven cadaveric lower leg specimens, 6 left and 5 right, were dissected using operative loupe magnification. We preserved the terminal branches and recorded their paths and branching patterns. Joint capsular innervations were individually noted. To confirm our hypothesis of significant dorsal midfoot joint capsular innervation by the DPN, we also performed an institutional review board-approved retrospective chart review of 37 patients with painful dorsal midfoot osteoarthritis who underwent diagnostic local anesthetic injection block of the DPN. The percentage of temporary pain relief after the injection was recorded.

RESULTS

Terminal innervation of the DPN branches showed distribution of the second and third tarsometatarsal joints in all specimens. Inconsistent innervation of the naviculocuneiform (9/11), fourth (7/11), first (6/11), and fifth (4/11) tarsometatarsal and calcaneocuboid joints (1/11) were observed. The retrospective review of pain relief in patients with dorsal midfoot pain due to arthritis after diagnostic injection demonstrated a mean of 92.1% improvement.

CONCLUSION

Innervation of the dorsal midfoot joint capsule appears to follow a consistent distribution across 3 joints: second and third tarsometatarsal joints and the naviculocuneiform joint. Acute relief of dorsal midfoot arthritic pain after diagnostic injection suggests that dorsal midfoot nociceptive pain is at least partly transmitted by the DPN.

LEVEL OF EVIDENCE

Level IV, case series.

Natural History of Radiographic First Metatarsophalangeal Joint Osteoarthritis: A Nineteen-Year Population-Based Cohort Study

OBJECTIVE

To assess the long-term prevalence, natural history, progression, and incidence of radiographic first metatarsophalangeal (MTP) joint osteoarthritis (OA).

METHODS

A longitudinal cohort design was used in which radiographic OA at the first MTP joint was investigated in participants from the Chingford 1,000 Women Study at year 6 (1995) and year 23 (2013-2015). Radiographic features of osteophytes (OPs) and/or joint space narrowing (JSN) at the first MTP joint were scored according to a validated foot atlas. Natural history was determined by the change in prevalence, incidence, progression, and worsening of OA in the first MTP joint.

RESULTS

Complete case-matched foot radiographic data were available for 193 of the women currently enrolled in the study (mean ± SD age 75.7 ± 5.2 years [range 69-90 years]). At the level of the first MTP joint, prevalence of OA at year 6 was 21.76% in the left and 24.35% in the right; at year 23, it was 23.83% in the left and 32.64% in the right. Over the 19-year period, 13.5% of the women developed incident OA in the right first MTP joint and 8.3% in the left. Both progression and worsening of OA were more evident for OPs and in the right first MTP joints.

CONCLUSION

In this study of the natural history of radiographic first MTP joint OA, which to our knowledge is the longest study to date, the prevalence and incidence of first MTP joint OA increased over a 19-year period. Progression and/or worsening of OA at the first MTP joint over time appears to be driven by OP development rather than JSN, which suggests a biomechanical cause.

Defining multiple joint osteoarthritis, its frequency and impact in a community-based cohort

BACKGROUND/PURPOSE

To update definitions of multiple joint osteoarthritis (MJOA), and to determine the frequency and impact of MJOA in a community-based cohort.

METHODS

Following PRISMA guidelines and with the help of a professional research librarian, we performed a systematic review in Medline using the terms osteoarthritis, generalized, polyarticular, multiple joint, and multi-joint among others, to obtain articles related to MJOA. A total of 42 articles were included for data extraction based on multiple criteria including the requirement for a clearly stated definition of OA assessed at more than one body site. We assessed frequency of these definitions in the Johnston County OA Project (JoCo OA) cohort as well as outcomes related to general health and physical function.

RESULTS

A total of 6 clearly stated definitions for MJOA were identified. These definitions were integrated with a list of 24 definitions from our previous systematic review and distilled down to produce 10 literature-derived, operationalized MJOA definitions. Based on these definitions, high frequencies of radiographic (4-74%) and symptomatic (2-52%) MJOA were found in the JoCo OA. Significant detrimental effects were seen on general health and physical function for most definitions.

CONCLUSIONS

We constructed a list of 10 summary MJOA definitions based in the literature that are frequent and associated with important clinical outcomes. These definitions capture some of the variability of MJOA phenotypes and provide a starting point for future analyses of both existing and newly initiated studies.

Foot osteoarthritis: latest evidence and developments

Foot osteoarthritis (OA) is a common problem in older adults yet is under-researched compared to knee or hand OA. Most existing studies focus on the first metatarsophalangeal joint, with evidence relating to midfoot OA being particularly sparse. Symptomatic radiographic foot OA affects 17% of adults aged 50 years and over. The first metatarsophalangeal joint is most commonly affected, followed by the second cuneometatarsal and talonavicular joints. Epidemiological studies suggest the existence of distinct first metatarsophalangeal joint and polyarticular phenotypes, which have differing clinical and risk factor profiles. There are few randomized controlled trials in foot OA. Existing trials provide some evidence of the effectiveness for pain relief of physical therapy, rocker-sole shoes, foot orthoses and surgical interventions in first metatarsophalangeal joint OA and prefabricated orthoses in midfoot OA. Prospective epidemiological studies and randomized trials are needed to establish the incidence, progression and prognosis of foot OA and determine the effectiveness of both commonly used and more novel interventions.

The effect of variation in interpretation of the La Trobe radiographic foot atlas on the prevalence of foot osteoarthritis in older women: the Chingford general population cohort

Background

The prevalence of foot osteoarthritis (OA) is much less understood than hip, knee and hand OA. The foot is anatomically complex and different researchers have investigated different joints with lack of methodological standardisation across studies. The La Trobe Foot Atlas (LFA) is the first to address these issues in providing quantitative assessment of radiographic foot OA, but has not been tested externally. The aim of this study was to evaluate three different interpretive approaches to using the LFA for grading OA when scoring is difficult due to indistinct views of interosseous space and joint contour.

Methods

Foot radiographs of all remaining participants (n = 218) assessed in the Chingford Women Study 23 year visit (mean (SD) for age: 75.5 years (5.1)) were scored using the LFA defined protocol (Technique 1). Two revised scoring strategies were applied to the radiographs in addition to the standard LFA analyses. Technique 2 categorised joints that were difficult to grade as ‘missing’. Technique 3 included joints that were difficult to grade as an over estimated score. Radiographic OA prevalence was defined for the foot both collectively and separately for individual joints.

Results

When radiographs were scored using the LFA (Technique 1), radiographic foot OA was present in 89.9%. For Technique 2 the presence of radiographic foot OA was 83.5% and for Technique 3 it was 97.2%. At the individual joint level, using Technique 1, the presence of radiographic foot OA was higher with a wider range (18.3–74.3%) than Technique 2 (17.9–46.3%) and lower with a wider range (18.3–74.3%) than Technique 3 (39.9–79.4%).

Conclusion

The three different ways of interpreting the LFA scoring system when grading of individual joints is technically difficult and result in very different estimates of foot OA prevalence at both the individual joint and global foot level. Agreement on the best strategy is required to improve comparability between studies.

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.

Hyaline cartilage calcification of the first metatarsophalangeal joint is associated with osteoarthritis but independent of age and BMI

Background

Hyaline cartilage calcification (CC) is associated with osteoarthritis (OA) in hip and knee joints. The first metatarsophalangeal joint (1^stMTPJ) is frequently affected by OA, but it is unclear if CC occurs in the 1^stMTPJ. The aim of the present study was to analyze the prevalence of CC of the 1^stMTPJ in the general population by high-resolution digital contact radiography (DCR) and to determine its association with histological OA severity, age and body mass index (BMI).

Methods

168 metatarsal heads of 84 donors (n = 47 male, n = 37 female; mean age 62.73 years, SD ±18.8, range 20–93) were analyzed by DCR for the presence of CC. Histological OA grade (hOA) by OARSI was analyzed in the central load-bearing zone of the first metatarsal head (1^st MH). Structural equation modeling (SEM) was performed to analyze the interrelationship between CC, hOA, age and BMI.

Results

The prevalence of CC of 1^stMH was 48.8 % (41/84) (95 %-CI [37.7 %, 60.0 %]), independent of the affected side (p = 0.42), gender (p = 0.41) and BMI (p = 0.51). The mean amount of CC of one MH correlated significantly with that of the contralateral side (r_s = 0.4, 95 %-CI [0.26, 0.52], p < 0.001). The mean amount of CC (in % of total cartilage area) of the MH correlated significantly with the severity of hOA (r_s = 0.51, 95 %-CI [0.32, 0.65], p < 0.001). SEM revealed significant associations between CC and hOA (r = 0.74, p < 0.001) and between hOA and age (β = 0.62, p = 0.001), but not between CC and age (p = 0.15). There was no significant influence of BMI on either CC (p = 0.37) or hOA (p = 0.16).

Conclusion

The observation that CC of the 1^stMH is significantly associated with the severity of OA but independent of age and BMI, suggests an intimate relationship between CC and the pathogenesis of OA, the exact nature of which will have to be explored by future studies.

Electronic supplementary material

The online version of this article (doi:10.1186/s12891-016-1324-0) contains supplementary material, which is available to authorized users.

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.

Investigations of Potential Phenotypes of Foot Osteoarthritis: Cross-Sectional Analysis From the Clinical Assessment Study of the Foot

OBJECTIVE

To investigate the existence of distinct foot osteoarthritis (OA) phenotypes based on pattern of joint involvement and comparative symptom and risk profiles.

METHODS

Participants ages ≥50 years reporting foot pain in the previous year were drawn from a population-based cohort. Radiographs were scored for OA in the first metatarsophalangeal (MTP) joint, first and second cuneometatarsal, navicular first cuneiform, and talonavicular joints according to a published atlas. Chi-square tests established clustering, and odds ratios (ORs) examined symmetry and pairwise associations of radiographic OA in the feet. Distinct underlying classes of foot OA were investigated by latent class analysis (LCA) and their association with symptoms and risk factors was assessed.

RESULTS

In 533 participants (mean age 64.9 years, 55.9% female) radiographic OA clustered across both feet (P < 0.001) and was highly symmetrical (adjusted OR 3.0, 95% confidence interval 2.1, 4.2). LCA identified 3 distinct classes of foot OA: no or minimal foot OA (64%), isolated first MTP joint OA (22%), and polyarticular foot OA (15%). After adjustment for age and sex, polyarticular foot OA was associated with nodal OA, increased body mass index, and more pain and functional limitation compared to the other classes.

CONCLUSION

Patterning of radiographic foot OA has provided insight into the existence of 2 forms of foot OA: isolated first MTP joint OA and polyarticular foot OA. The symptom and risk factor profiles in individuals with polyarticular foot OA indicate a possible distinctive phenotype of foot OA, but further research is needed to explore the characteristics of isolated first MTP joint and polyarticular foot OA.

Manipulative and Multimodal Therapies in the Treatment of Osteoarthritis of the Great Toe: A Case Series

OBJECTIVE

The objective of this case series is to describe manual manipulative therapy with exercise for 3 patients with mild to moderate osteoarthritis of the great toe.

CLINICAL FEATURES

Three patients, a 32-year-old man, a 55-year-old woman, and a 49-year-old woman, had great toe pain of 8, 1, and 2 years, respectively. Each had a palpable exostosis, a benign outgrowth of bone projecting outward from the bone surface, and decreased dorsiflexion with a hard end-feel.

INTERVENTION AND OUTCOME

Manual manipulative therapy with exercise, the Brantingham protocol, was used with patients receiving 6, 9, and 12 treatments over 6 weeks. Specific outcome measures for hallux rigidus and the foot were chosen to document the effects of this intervention including digital inclinometry, the lower extremity functional scale, the foot functional index, overall therapy effectiveness and Visual Analogue Scale (VAS). Each patient had an increase in range of motion that surpassed the minimal clinically important change, an increase in the overall therapy effectiveness and a decrease in the foot functional index that surpassed the minimally clinically important difference. Most importantly for the patients, each reported a decrease in both usual and worst pain on the VAS that exceeded the minimally clinically important difference of 20 to 30 mm.

CONCLUSION

The 3 patients reported decreased pain measured by the VAS, increased range of motion and minimally clinically important difference in 3 other outcome measures.

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.

The population prevalence of symptomatic radiographic foot osteoarthritis in community-dwelling older adults: cross-sectional findings from the clinical assessment study of the foot

OBJECTIVES

To estimate the population prevalence of symptomatic radiographic osteoarthritis (OA) affecting the 1st metatarsophalangeal joint (MTPJ), 1st and 2nd cuneometatarsal joints (CMJs), navicular first cuneiform joint (NCJ) and talonavicular joint (TNJ) in community-dwelling older adults.

METHODS

9334 adults aged ≥50 years registered with four general practices were mailed a health survey. Responders reporting foot pain within the last 12 months were invited to undergo weight-bearing dorso-plantar and lateral radiographs of both feet. OA at the 1st MTPJ, 1st and 2nd CMJs, NCJ and TNJ was graded using a validated atlas. Population prevalence estimates for symptomatic radiographic foot OA overall and for each joint were calculated using multiple imputation and weighted logistic regression modelling to account for missing data and non-response.

RESULTS

5109 health surveys were received (adjusted response 56%). Radiographs were obtained on 557 participants. Overall population prevalence of symptomatic radiographic OA was 16.7% (95% CI 15.3% to 18.0%), 1st MTPJ 7.8% (6.7% to 8.9%), 1st CMJ 3.9% (2.9% to 4.9%), 2nd CMJ 6.8% (5.7% to 7.8%), NCJ 5.2% (4.0% to 6.4%) and TNJ 5.8% (4.8% to 6.9%). With the exception of the 1st CMJ, prevalence was greater in females than males, increased with age and was higher in lower socioeconomic classes. Three-quarters of those with symptomatic radiographic OA reported disabling foot symptoms.

CONCLUSIONS

While cautious interpretation due to non-response is warranted, our study suggests that symptomatic radiographic foot OA affects one in six older adults and the majority report associated disability. Clinicians should consider OA as a possible cause of chronic foot pain in older people.

Midfoot and forefoot osteoarthritis

BACKGROUND

Foot osteoarthritis (OA) is linked with chronic foot pain and functional impairment.

OBJECTIVE

To review the current knowledge on midfoot and forefoot OA.

METHODS

PubMed, CINAHL, PEDro, and the ISI Web of Science databases (1950-2013) were searched for keywords: foot OA, midfoot OA, forefoot OA and metatarsal OA. The search was limited to reports in human subjects and English language. Published cohort, cross-sectional studies and clinical trials relating to epidemiology, clinical features, functional impairment, risk factors and treatment were included.

RESULTS

We found heterogeneity in the design, radiographic views and grading systems used among studies. Most of the literature focused on radiographic OA, being the prevalence between 0.1% and 61%, depending on gender, age and joint evaluated. The age and female gender were the main associated factors, whereas structural (bone length) and mechanical factors (hypermobility, altered tarso-metatarsal stress, etc.) seemed to be related. Various treatments are widely used, i.e. physical therapy, orthotics, steroid injection, analgesics and arthrodesis. However, scarce research supports their efficacy.

CONCLUSION

Most of the current knowledge comes from observational and small case-control studies. Future population-based studies as well as controlled studies are essential to understand the risk factors and to evaluate the effectiveness of treatment options.

Correlates of foot pain severity in adults with hallux valgus: a cross-sectional study

Background

Hallux valgus (HV) is highly prevalent and associated with progressive first metatarsophalangeal joint subluxation and osteoarthritis. The link between structural HV deformity and foot pain is unclear. This study investigated possible explanatory factors surrounding foot pain in HV, including radiographic HV angle and signs of joint degeneration.

Methods

Participants were 60 adults (53 female) with HV aged 20 to 75 years. Participant demographics and a range of radiographic, clinical and functional measures were considered potential correlates of foot pain. Self-reported foot pain (visual analogue scales and a dichotomous definition) was considered the dependent variable. Multivariate modelling was used to determine which characteristics and measures explained pain, with univariate analyses first used to screen potential variables.

Results

Approximately 20 to 30% of the variance in foot pain associated with HV could be explained by patient characteristics such as poorer general health status, lower educational attainment and increased occupational physical activity levels, in combination with some dynamic physical characteristics such as hallux plantarflexion weakness and reduced force-time integral under the second metatarsal during gait. Neither increasing lateral deviation of the hallux (HV angle) nor presence of first metatarsophalangeal joint osteoarthritis was associated with foot pain.

Conclusions

This study shows that passive structural factors, including HV angle, do not appear to be significant correlates of foot pain intensity in HV. Our data demonstrate the importance of considering patient characteristics such as general health and physical activity levels when assessing foot pain associated with HV.

Imaging of tarsal navicular disorders: a pictorial review

The tarsal navicular is a bone within the midfoot that plays a critical role in maintaining the arch of the foot. This bone is clinically relevant because it may be affected by a wide array of pathologies. Our approach includes a detailed description of the imaging characteristics and disorders affecting the tarsal navicular. Organization includes (a) normal imaging, (b) accessory ossicles, (c) coalition, (d) fractures, (e) Kohler's disease, (f) osteonecrosis, (g) osteochondral lesions, (h) arthropathies, and (i) tumors. The purpose of this article is to discuss normal variants and pathological processes that can affect the tarsal navicular, with emphasis on the often-overlooked imaging findings.

Rocker-sole footwear versus prefabricated foot orthoses for the treatment of pain associated with first metatarsophalangeal joint osteoarthritis: study protocol for a randomised trial

BACKGROUND

Osteoarthritis affecting the first metatarsophalangeal joint of the foot is a common condition which results in pain, stiffness and impaired ambulation. Footwear modifications and foot orthoses are widely used in clinical practice to treat this condition, but their effectiveness has not been rigorously evaluated. This article describes the design of a randomised trial comparing the effectiveness of rocker-sole footwear and individualised prefabricated foot orthoses in reducing pain associated with first metatarsophalangeal joint osteoarthritis.

METHODS

Eighty people with first metatarsophalangeal joint osteoarthritis will be randomly allocated to receive either a pair of rocker-sole shoes (MBT® Matwa, Masai Barefoot Technology, Switzerland) or a pair of individualised, prefabricated foot orthoses (Vasyli Customs, Vasyli Medical™, Queensland, Australia). At baseline, the biomechanical effects of the interventions will be examined using a wireless wearable sensor motion analysis system (LEGSys™, BioSensics, Boston, MA, USA) and an in-shoe plantar pressure system (Pedar®, Novel GmbH, Munich, Germany). The primary outcome measure will be the pain subscale of the Foot Health Status Questionnaire (FHSQ), measured at baseline and 4, 8 and 12 weeks. Secondary outcome measures will include the function, footwear and general foot health subscales of the FHSQ, severity of pain and stiffness at the first metatarsophalangeal joint (measured using 100 mm visual analog scales), global change in symptoms (using a 15-point Likert scale), health status (using the Short-Form-12® Version 2.0 questionnaire), use of rescue medication and co-interventions to relieve pain, the frequency and type of self-reported adverse events and physical activity levels (using the Incidental and Planned Activity Questionnaire). Data will be analysed using the intention to treat principle.

DISCUSSION

This study is the first randomised trial to compare the effectiveness of rocker-sole footwear and individualised prefabricated foot orthoses in reducing pain associated with osteoarthritis of the first metatarsophalangeal joint, and only the third randomised trial ever conducted for this condition. The study has been pragmatically designed to ensure that the findings can be implemented into clinical practice if the interventions are found to be effective, and the baseline biomechanical analysis will provide useful insights into their mechanism of action.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry: ACTRN12613001245785.

Fourteen years follow up after Lisfranc fracture-dislocation: functional and radiological results

Injuries to the Lisfranc joint have a high potential for chronic disability. Posttraumatic arthritis remains the most common complication but not all patients who develop degenerative radiographic changes are symptomatic. A cohort of 32 patients with a Lisfranc fracture dislocation was reviewed. Initial reduction and secondary displacement were measured by the Myerson scale. Radiographic evidence of osteoarthritis (OA) was also investigated. Long-term radiographical data were classified as good, fair or poor results. Functional outcome was measured using several different scales. Mean follow up was 14 years. Seventeen patients with anatomic close reduction but instability were treated with closed reduction and K-wire fixation followed by cast immobilisation. Eight patients with stable anatomic close reduction were treated with closed reduction and cast. Seven patients with unacceptable closed reduction were treated with open reduction and K-wire stabilisation. The analysis of radiological long-term data showed 15 patients with good results, 8 with fair results and 9 with poor results. Final mean AOFAS score was 91.7/100. There was no statistically significant difference between overall PFS scores and different type of treatment, Hardcastle long-term radiological scores or Hardcastle type of fracture (p >0.05). Overall, there was a poor association between the extent of radiological arthritis and clinical scores. We advocate that for the evaluation of long-term outcome of these injuries functional parameters should be the focus of assessment, instead of radiological changes.

Midfoot arthritis: diagnosis and treatment

BACKGROUND

Midfoot arthritis is a challenging problem causing chronic foot pain and impeding daily activity. There is not much written about this subject in literature and is often not well known by orthopaedic surgeons. The primary aim of treatment is to afford pain relief by enhancing midfoot stability and modifying loads sustained at the inflamed joints. The initial treatment is conservative with inserts and orthoses. Surgery, more specifically midfoot arthrodesis, is the next step when conservative management fails. The arthrodesis should be limited to the symptomatic joints but it is often difficult to determine which joints cause the symptoms. With this manuscript we would like to underline the importance of a precise anatomic preoperative diagnosis, review our surgical experience and discuss the different surgical fixation possibilities in midfoot arthrodesis.

METHODS

Between 2006 and 2011 24 patients (26 feet) with midfoot osteoarthritis underwent selective arthrodesis after conservative management had failed. Preoperative examinations, fixation method, complications and outcome were noted.

RESULTS

We achieved union in 25 feet. There was one delayed union and one non-union. There were no infections but 3 patients had chronic regional pain syndrome. Reoperation was required in one foot because of non-union and one for symptomatic hardware removal.

CONCLUSION

Midfoot arthrodesis is an effective treatment for osteoarthritis of the joint. Identification of the affected joints is important to stipulate the extensiveness of the arthrodesis.

Factors associated with foot pain severity and foot-related disability in individuals with first metatarsophalangeal joint OA

OBJECTIVE

To determine whether participant characteristics and localized structural factors are associated with foot pain and foot-related disability in patients with symptomatic first MTP joint OA.

METHODS

One hundred and fifty-one participants (56 women and 95 men) aged 22-81 [mean age 54.5 (11.2)] years with symptomatic first MTP joint OA underwent a standardized clinical interview and assessment. Participant characteristics [age, gender, height, weight, BMI, duration of symptoms and total years of formal education (education attainment)] and localized factors (first MTP joint dorsiflexion range of motion, severity of radiographic OA, foot posture and plantarflexion strength of the hallux) were determined as potentially associated variables. Outcome variables were foot pain and foot-related disability, determined using the Foot Health Status Questionnaire. Univariate analyses were performed between potentially associated variables and outcome variables. Variables with significant univariate associations were then entered into multivariate linear regression models to identify independently associated variables.

RESULTS

Education attainment and BMI were both significantly and independently associated with foot pain severity and foot-related disability. However, these variables only explained ∼10-12% of the variance in foot pain and foot-related disability.

CONCLUSIONS

People with symptomatic first MTP joint OA that have an increased BMI and/or lower level of education attainment experience more foot pain and have greater foot-related disability. Prospective studies are required to confirm these findings and identify other factors associated with foot pain and foot-related disability in people with symptomatic first MTP joint OA.

Development of a diagnostic rule for identifying radiographic osteoarthritis in people with first metatarsophalangeal joint pain

OBJECTIVE

To develop a diagnostic rule for the identification of radiographic osteoarthritis (OA) of the first metatarsophalangeal joint (MTPJ) in people with first MTPJ pain.

DESIGN

Symptoms and clinical observations were documented in 181 people with first MTPJ pain, and the presence of OA was confirmed using plain film radiography. Diagnostic test statistics were calculated to assess the ability of symptoms and clinical observations to identify radiographic OA. Multivariate logistic regression was used to develop two diagnostic models: a statistically optimal model and a simplified clinical model.

RESULTS

Multivariate logistic regression identified pain duration greater than 25 months, the presence of a dorsal exostosis, hard-end feel, crepitus and less than 64° of first MTPJ dorsiflexion to be significantly associated with radiographic OA. The statistically optimal model and clinical model performed similarly, with the areas under the receiver operating characteristics curves being 0.87 (95% confidence interval [CI] 0.81-0.93) and 0.87 (95% CI 0.80-0.93), respectively, and the percentage of cases correctly classified being 86.2 and 85.6, respectively. A cut-off score of ≥3 using the clinical model resulted in a sensitivity of 88%, specificity of 71%, accuracy of 84%, positive likelihood ratio of 3.07 and negative likelihood ratio of 0.17.

CONCLUSIONS

In people with first MTPJ pain, a model consisting of five clinical observations can accurately identify the presence or absence of radiographic OA. The application of this diagnostic rule may assist clinical decision making and potentially reduce the need for referral for radiographs.

Radiographic correlates of hallux valgus severity in older people

Background

The severity of hallux valgus is easily appreciated by its clinical appearance, however x-ray measurements are also frequently used to evaluate the condition, particularly if surgery is being considered. There have been few large studies that have assessed the validity of these x-ray observations across a wide spectrum of the deformity. In addition, no studies have specifically focused on older people where the progression of the disorder has largely ceased. Therefore, this study aimed to explore relationships between relevant x-ray observations with respect to hallux valgus severity in older people.

Methods

This study utilised 402 x-rays of 201 participants (74 men and 127 women) aged 65 to 94 years. All participants were graded using the Manchester Scale - a simple, validated system to grade the severity of hallux valgus - prior to radiographic assessment. A total of 19 hallux valgus-related x-ray observations were performed on each set of x-rays. These measurements were then correlated with the Manchester Scale scores.

Results

Strong, positive correlations were identified between the severity of hallux valgus and the hallux abductus angle, the proximal articular set angle, the sesamoid position and congruency of the first metatarsophalangeal joint. As hallux valgus severity increased, so did the frequency of radiographic osteoarthritis of the first metatarsophalangeal joint and a round first metatarsal head. A strong linear relationship between increased relative length of the first metatarsal and increased severity of hallux valgus was also observed.

Conclusions

Strong associations are evident between the clinical appearance of hallux valgus and a number of hallux valgus-related x-ray observations indicative of structural deformity and joint degeneration. As it is unlikely that metatarsal length increases as a result of hallux valgus deformity, increased length of the first metatarsal relative to the second metatarsal may be a contributing factor to the development and/or progression of hallux valgus.

A systematic review of radiographic definitions of foot osteoarthritis in population-based studies

OBJECTIVE

To identify the methods used in population-based epidemiological studies to diagnose radiographic foot osteoarthritis (OA) and to estimate the population prevalence of radiographic foot OA.

METHOD

Electronic databases searched included Medline, Embase, CINAHL and Ageline (inception to May 2009). The search strategy combined search terms for radiography, OA, foot, and specific foot joints. Predetermined selection criteria were applied. Data extracted from each paper included: sample population, radiographic views taken, foot joints examined, scoring system used, definition of OA applied, reliability of radiographic scoring and prevalence of radiographic OA in the foot.

RESULTS

Titles and abstracts of 1035 papers were reviewed and full-texts of 21 papers were obtained. Fifteen papers met inclusion criteria and a further 12 papers were included after screening references. Radiographic views were frequently not specified (NS) but a combination of antero-posterior (AP) and lateral (Lat) views was most commonly reported. The first metatarsophalangeal (MTP) joint was the most commonly examined joint (n=20, 74%). Nineteen studies (70%) used the Kellgren and Lawrence (K&L) grading system, 95% of which defined OA as K&L grade> or =2. Estimates of the prevalence of radiographic first MTP joint OA (defined as K&L> or =2) in middle-aged to older adults ranged from 6.3 to 39%. Significant statistical heterogeneity prevented pooling of prevalence estimates.

CONCLUSION

There are comparatively few studies examining radiographic foot OA. Existing studies mainly focus on the first MTP joint and use the K&L grading system. Future studies are needed to quantify the prevalence of radiographic OA at the different joint complexes within the foot.

Foot structure and function in older people with radiographic osteoarthritis of the medial midfoot

OBJECTIVE

To investigate whether foot structure and dynamic foot function differ between older people with and without radiographically confirmed osteoarthritis (OA) of the talo-navicular joint (TNJ) and navicular-first cuneiform joint (N1(st)CJ).

METHOD

Dorso-plantar and lateral weighbearing foot radiographs (right feet) were obtained from 205 older people aged 61-94 years, and the presence of OA in the TNJ and N1(st)CJ was determined using a standardized atlas. Foot structure was assessed using a clinical measure (the arch index [AI]) and two radiographic measures (calcaneal inclination angle [CIA] and calcaneal-first metatarsal angle [C1MA]). Dynamic plantar pressure assessment during walking was undertaken using the Tekscan MatScan system.

RESULTS

Thirty-five participants exhibited radiographic OA in the TNJ and N1(st)CJ. There were no significant differences between the groups in relation to age, sex, weight or walking velocity. Compared to those without OA in these joints, those with OA had significantly flatter feet, as evidenced by larger AI (0.26+/-0.05 vs 0.25+/-0.05, P=0.02), smaller CIA (18.5+/-6.3 vs 21.3+/-5.4 degrees, P<0.01) and larger C1MA (137.0+/-9.3 vs 132.4+/-8.0 degrees, P<0.01), and exhibited significantly higher maximum forces in the midfoot (15.2+/-7.3 vs 11.2+/-7.0 kg, P<0.01; 36% increase).

CONCLUSION

Older people with radiographic OA of the TNJ and N1(st)CJ exhibit flatter feet and increased loading of the plantar midfoot when walking. Excessive loading of the midfoot may predispose to OA by increasing dorsal compressive forces, although prospective studies are required to confirm whether this relationship is causal.