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

Preoperative Degenerative Changes at the Tibial Sesamoid-Metatarsal Joint in Hallux Valgus: Association With Postoperative Patient-Reported Outcomes After Modified Lapidus Procedure

Background

Degenerative changes at the sesamoid-metatarsal joints (SMJs) may be a source of pain following hallux valgus surgery. The aims of this study were to describe degenerative changes at the SMJs on weightbearing computed tomography (WBCT) scans and, secondarily, investigate their association with 1-year patient-reported outcome scores following a modified Lapidus procedure for hallux valgus. We hypothesized that reduced joint space in the SMJs would correlate with worse patient-reported outcomes.

Methods

Fifty-seven hallux valgus patients who underwent a modified Lapidus procedure had preoperative and minimum 5-month postoperative WBCT scans, and preoperative and at least 1-year postoperative PROMIS physical function (PF), pain interference, and pain intensity scores were included. Degenerative changes at the SMJs were measured using distance mapping between the sesamoids and first metatarsal head on preoperative and postoperative WBCT scans. The minimum and average distances between the first metatarsal head and tibial sesamoid (tibial-SMJ) for each patient preoperatively and postoperatively were measured. Sesamoid station was measured on WBCT scans using a 0 to 3 grading system. Linear regression was used to investigate the correlations between minimum preoperative and postoperative tibial-SMJ distances and 1-year postoperative PROMIS scores.

Results

The median minimum and average tibial-SMJ distances increased from 0.82 mm (interquartile range [IQR] 0.40-1.03 mm) and 1.62 mm (IQR 1.37-1.75 mm) preoperative to 1.09 mm (IQR 0.96-1.23 mm) and 1.73 mm (IQR 1.60-1.91 mm) postoperative (P < .001 and P < .001), respectively. In a subset of patients with complete sesamoid reduction, we found an association between preoperative minimum tibial-SMJ distance and 1-year postoperative PROMIS PF scores (coefficient 7.2, P = .02).

Conclusion

Following the modified Lapidus procedure, there was a statistically significant increase in the tibial-SMJ distance. Additionally, in patients with reduced sesamoids postoperatively, reduced preoperative tibial-SMJ distance correlated with worse PROMIS PF scores.

Level of Evidence

Level IV, case series.

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

BACKGROUND

The first metatarsophalangeal joint is the most common site of osteoarthritis (OA) in the foot and ankle. Intra-articular corticosteroid injections are widely used for this condition, but little is known about their use in practice. This study explored current practice within the UK National Health Service (NHS) relating to the administration of intra-articular corticosteroids for people with painful first metatarsophalangeal joint (MTPJ) OA.

METHODS

A cross-sectional survey using Qualtrics online survey platform (Qualtrics, Provo, UT, USA), distributed through professional bodies, special interest groups, and social media.

RESULTS

One hundred forty-four healthcare professionals responded, including podiatrists (53/144; 39%), orthopaedic surgeons (28/144; 19%), podiatric surgeons (26/144; 17%) and physiotherapists (24/144; 16%). Half of respondents administered up to 25 corticosteroid injections per year (67/136; 49%) but some administered more than fifty (21/136; 15%). Injections were administered across the healthcare system but were most common in hospital settings (64/136; 44%) followed by community (38/136; 26%), with less delivered in primary care (11/136; 8%). Half of respondents routinely used image-guidance, either ultrasound or x-ray/fluoroscopy (65/136; 48%) although over one third used none (52/136; 38%). Imaging guidance was more common amongst medical professionals (21/31; 68%) compared to non-medical health professionals (45/105; 43%). Overall, methylprednisolone acetate was the most common corticosteroid used. Medical professionals mostly injected methylprednisolone acetate (n = 15/27; 56%) or triamcinolone acetonide (n = 11/27; 41%), whereas premixed methylprednisolone acetate with lidocaine hydrochloride was the most common preparation used by non-medical health professionals (41/85; 48%). When injecting non premixed steroid, lidocaine hydrochloride (15/35; 43%) was the most common choice of local anaesthetic for non-medical health professionals but medical professionals showed more variation between lidocaine hydrochloride (8/23; 35%) levobupivacaine hydrochloride (9/23; 39%) and bupivacaine hydrochloride (5/23; 22%).

CONCLUSIONS

Multiple professional groups regularly administer intra-articular corticosteroids for symptomatic first MTPJ OA across a range of NHS healthcare settings. Overall, methylprednisolone acetate was the most commonly administered steroid and lidocaine hydrochloride the most common local anaesthetic. There was large variation in the use of imaging guidance, type and dose of steroid, local anaesthetic, and clinical pathways used in the intra-articular injection of corticosteroids for people with first MTPJ OA.

Toward improved understanding of foot shape, foot posture, and foot biomechanics during running: A narrative review

The current narrative review has explored known associations between foot shape, foot posture, and foot conditions during running. The artificial intelligence was found to be a useful metric of foot posture but was less useful in developing and obese individuals. Care should be taken when using the foot posture index to associate pronation with injury risk, and the Achilles tendon and longitudinal arch angles are required to elucidate the risk. The statistical shape modeling (SSM) may derive learnt information from population-based inference and fill in missing data from personalized information. Bone shapes and tissue morphology have been associated with pathology, gender, age, and height and may develop rapid population-specific foot classifiers. Based on this review, future studies are suggested for 1) tracking the internal multi-segmental foot motion and mapping the biplanar 2D motion to 3D shape motion using the SSM; 2) implementing multivariate machine learning or convolutional neural network to address nonlinear correlations in foot mechanics with shape or posture; 3) standardizing wearable data for rapid prediction of instant mechanics, load accumulation, injury risks and adaptation in foot tissue and bones, and correlation with shapes; 4) analyzing dynamic shape and posture via marker-less and real-time techniques under real-life scenarios for precise evaluation of clinical foot conditions and performance-fit footwear development.

Summary Report of the Arthritis Foundation and the American Orthopaedic Foot & Ankle Society's Symposium on Targets for Osteoarthritis Research: Part 1: Epidemiology, Pathophysiology, and Current Imaging Approaches

This first of a 2-part series of articles recounts the key points presented in a collaborative symposium sponsored jointly by the Arthritis Foundation and the American Orthopaedic Foot & Ankle Society with the intent to survey the state of scientific knowledge related to incidence, diagnosis, pathologic mechanisms, and injection treatment options for osteoarthritis (OA) of the foot and ankle. A meeting was held virtually on December 3, 2021. A group of experts were invited to present brief synopses of the current state of knowledge and research in this area. Part 1 overviews areas of epidemiology and pathophysiology, current approaches in imaging, diagnostic and therapeutic injections, and genetics. Opportunities for future research are discussed. The OA scientific community, including funding agencies, academia, industry, and regulatory agencies, must recognize the needs of patients that suffer from arthritis of foot and ankle. The foot and ankle contain a myriad of interrelated joints and tissues that together provide a critical functionality. When this functionality is compromised by OA, significant disability results, yet the foot and ankle are generally understudied by the research community. Level of Evidence: Level V - Review Article/Expert Opinion.

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.

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.

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.

[Mini implants in foot and ankle surgery: an alternative to total joint replacement or joint fusion]

Mini implants are increasingly used in foot and ankle surgery. They preserve the joints' functions, are easy to insert and easy to convert to an alternative treatment. Early surgical attempts using silastic implants did not bring the expected success. First achievements where reached with modern metallic mini implants in the first metatarsophalangeal (MTP) joint and the ankle joint. For a few years now, a polyvinyl alcohol implant has been used to treat the arthritic first MTP joint. Even severe arthritic joints can be treated with an implant made of polylactide. This implant can also be used in the treatment of Lisfranc joint pathologies. To address severe osteochondral defects of the talus, an innovative hemiarthroplasty implant has been suggested. This article gives a summary of currently used mini implants. Their application as possible alternatives to total joint replacement or joint fusion are critically reviewed in the light of the current literature.

Foot structure and lower limb function in individuals with midfoot osteoarthritis: a systematic review

OBJECTIVE

To determine how foot structure and lower limb function differ between individuals with and without midfoot osteoarthritis (OA).

DESIGN

Electronic databases were searched from inception until May 2020. To be eligible, studies needed to (1) include participants with radiographically confirmed midfoot OA, with or without midfoot symptoms, (2) include a control group of participants without radiographic midfoot OA or without midfoot symptoms, and (3) report outcomes of foot structure, alignment, range of motion or any measures of lower limb function during walking. Screening and data extraction were performed by two independent assessors, with disagreements resolved by a third independent assessor. The methodological quality of included studies was assessed using the National Institutes of Health Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies.

RESULTS

A total of 1,550 records were screened by title and abstract and 11 met the inclusion criteria. Quantitative synthesis indicated that individuals who had midfoot OA had a more pronated foot posture, greater first ray mobility, less range of motion in the subtalar joint and first metatarsophalangeal joints, longer central metatarsals and increased peak plantar pressures, pressure time integrals and contact times in the heel and midfoot during walking. Meta-analysis could not be performed as the data were not sufficiently homogenous.

CONCLUSIONS

There are several differences in foot structure and lower limb function between individuals with and without midfoot OA. Future research with more consistent case definitions and detailed biomechanical models would further our understanding of potential mechanisms underlying the development of midfoot OA.

Disability, Physical Impairments, and Poor Quality of Life, Rather Than Radiographic Changes, Are Related to Symptoms in Individuals With Ankle Osteoarthritis: A Cross-sectional Laboratory Study

OBJECTIVE

To compare physical and patient-reported outcomes between (1) individuals with symptomatic radiographic ankle osteoarthritis (OA) and asymptomatic individuals, and (2) asymptomatic individuals with and without radiographic ankle OA.

DESIGN

Cross-sectional study.

METHODS

Ninety-six volunteers (31 symptomatic individuals with radiographic ankle OA, 41 asymptomatic individuals with radiographic ankle OA, and 24 asymptomatic individuals without radiographic ankle OA) completed a survey on quality of life (QoL), function, pain, disability, kinesiophobia, ankle instability, and physical activity, and undertook physical assessments of ankle muscle strength, heel-raise endurance, dorsiflexion range of motion (ROM), and ambulatory function.

RESULTS

Symptomatic individuals with radiographic ankle OA reported greater pain (standardized mean difference [SMD], 1.70; 95% confidence interval [CI]: 1.18, 2.23), disability (SMD, 1.44; 95% CI: 0.93, 1.95), and instability (SMD, -3.92; 95% CI: -4.68, -3.17), and lower patient-reported function (SMD, -2.10; 95% CI: -2.66, -1.54) and QoL (SMD, -0.98; 95% CI: -1.47, -0.50), than asymptomatic individuals. Muscle strength (all SMDs, -0.73 or greater), heel-raise endurance (SMD, -0.71; 95% CI: -1.16, -0.25), dorsiflexion ROM (SMD, -1.54; 95% CI: -2.02, -1.06), and ambulatory function (all SMDs, 0.57 or greater) were significantly impaired in symptomatic individuals with radiographic ankle OA compared to asymptomatic individuals. Most patient-reported and physical outcomes were similar between asymptomatic individuals with and without radiographic ankle OA.

CONCLUSION

Individuals with symptomatic radiographic ankle OA had poorer physical outcomes, function, and QoL compared to asymptomatic individuals with and without radiographic ankle OA. This suggests that disability in ankle OA is related to symptoms rather than to radiographic evidence of degeneration. J Orthop Sports Phys Ther 2020;50(12):711-722. doi:10.2519/jospt.2020.9376.

Correlation of 3D Joint Space Width From Weightbearing CT With Outcomes After Intra-articular Calcaneal Fracture

BACKGROUND

Posttraumatic osteoarthritis (PTOA) of the subtalar joint is a serious, disabling, and frequent complication following intra-articular calcaneal fractures (IACFs). Using plain radiographs to assess the subtalar joint for PTOA is imprecise and insensitive, hindering progress toward improving treatment and assessing outcomes. This study explored how low-dose weightbearing computed tomography (WBCT) can be used to provide reliable, quantitative 3D measures of subtalar joint space width (JSW) following IACF and correlated the 3D JSW with clinical outcomes.

METHODS

After institutional review board approval, 21 patients (15 male; age, 28-70 years) who sustained IACFs and were treated with percutaneous surgical reduction underwent WBCT scans at follow-up visits 2 to 15 years (average, 7.8 years) after surgical treatment. Subtalar joint 3D JSW was computed after a semiautomated protocol was used to segment the talus and calcaneus from the WBCT data. Mean and minimum 3D JSW measurements were calculated and compared with Kellgren-Lawrence (KL) radiographic osteoarthritis grade, RAND-36 Physical (PCS) and Mental (MCS) Component Scores, and visual analog scale (VAS) pain scores. Spearman's rank correlation was used to detect the strength of association between variables, with significance set at P < .05.

RESULTS

Mean 3D JSW values measured from WBCT for patients with IACFs ranged from 0.9 to 2.5 mm (1.7 ± 0.4 mm) over the entire subtalar joint. Intra- and interrater reliabilities for the WBCT-based JSW measurement technique were 0.95 (95% CI, 0.91-0.97) and 0.97 (95% CI, 0.95-0.98), respectively. Mean and minimum 3D JSW values correlated inversely with VAS pain scores and KL grade (P < .05), particularly in central and posterior subtalar regions.

CONCLUSION

WBCT-based methods were used to quantify the preservation/loss of JSW in patients with IACFs, enabling more accurate, definitive measurement of subtalar PTOA. The results of this study demonstrate that WBCT can be utilized to objectively assess subtalar PTOA and help us to better understand how arthritic changes affect actual patient experience.

LEVEL OF EVIDENCE

Level III, prognostic comparative study.

Relative prevalence and distribution of knee, hand and foot symptomatic osteoarthritis subtypes in an English population

In this brief report, we used data from a series of three related cohorts on pain and osteoarthritis (OA) of the knee, hand and foot, which were conducted in North Staffordshire, England. We used a common approach for sampling, data collection and coding, to estimate the relative prevalence of 10 different symptomatic radiographic OA subtypes in the knee, hand and foot and to compare their association with age, sex, socioeconomic position and body mass index. Overall, symptomatic hand OA was more common than knee or foot OA (22.4% vs 17.4% vs 16.5%), due mainly to the high prevalence of nodal interphalangeal joint OA among women. The first carpometacarpal joint OA was the most frequent subtype, with patellofemoral, tibiofemoral, (nodal) interphalangeal and midfoot OA also common. Of the risk factors examined, the greatest differences between subtypes appeared to be their associations with sex and obesity: sex differences were noticeably greater for all forms of hand OA except non-nodal interphalangeal joint OA, while obesity appeared most strongly associated with forms of knee OA. The prevalence of all subtypes was higher among older ages, and among those with lower educational attainment.

Osteoarthritis in England: Incidence Trends From National Health Service Hospital Episode Statistics

Objective

It is typical in epidemiological research of osteoarthritis (OA) to collect data for the hand, hip, and knee. However, little population‐based data exist for this disease in the foot. Thus, we addressed patterns of OA for the foot compared with the hand, hip, and knee spanning 2000/2001 to 2017/2018 in England.

Methods

Secondary‐care data from 3 143 928 patients with OA of the foot, hand, hip, and knee were derived from the National Health Service (NHS) Hospital Episode Statistics (HES) database. Distribution, population prevalence, and incidence of joint‐specific OA were stratified by age and sex.

Results

OA incidence increased significantly at the foot [3.8% (95% confidence interval [CI] 3.0, 4.6)], hand [10.9% (10.1, 11.7)], hip [3.8% (2.9, 4.7)], and knee [2.9% (2.2, 3.6)] per year from 2000/2001 to 2017/2018. A higher proportion of women were diagnosed with OA, whereas greater incidence in men was estimated for the hand and hip. Foot OA presented comparable diagnosis numbers to the hand. More recently during 2012/2013 to 2017/2018, a significant rise in hip OA was estimated among younger adults, whereas knee OA decreased across all age groups. Incidence of OA in the foot and hand were particularly significant among the 75 or older age group, though bimodal age distributions were observed for both sites.

Conclusion

The significant increase in secondary care records for OA in England underscores the importance of exploring possible causative factors and identifying groups most at risk. Further detailed data may be particularly important for the hip, which represents significant incidence among younger adults. Greater incidence of OA in the foot compared with the knee emphasizes the need for well‐conducted epidemiological research in this area. Monitoring the performance of surgical outcomes at the population‐level for this frequently affected yet understudied site could have substantial potential to reduce the socioeconomic burden it represents to the NHS.

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.

Population prevalence and distribution of ankle pain and symptomatic radiographic ankle osteoarthritis in community dwelling older adults: A systematic review and cross-sectional study

OBJECTIVES

To identify by systematic review published prevalence estimates of radiographic ankle osteoarthritis (OA) and to subsequently estimate the prevalence of ankle pain and symptomatic, radiographic ankle OA within community-dwelling older adults from North Staffordshire, UK.

METHODS

Electronic databases were searched using terms for ankle, osteoarthritis and radiography. Data regarding population, radiographic methods, definitions and prevalence estimates of ankle OA were extracted from papers meeting predetermined selection criteria. Adults aged ≥50 years and registered with four general practices in North Staffordshire were mailed a health questionnaire. Ankle pain in the previous month was determined using a foot and ankle pain manikin. Respondents reporting pain in or around the foot in the last 12 months were invited to attend a research clinic where weight-bearing, antero-posterior and lateral ankle radiographs were obtained and scored for OA using a standardised atlas. Prevalence estimates for ankle pain and symptomatic, radiographic ankle OA were calculated using multiple imputation and weighted logistic regression, and stratified by age, gender and socioeconomic status.

RESULTS

Eighteen studies were included in the systematic review. The methods of radiographic classification of ankle OA were poorly reported and showed heterogeneity. No true general population prevalence estimates of radiographic ankle OA were found, estimates in select sporting and medical community-dwelling populations ranged from 0.0-97.1%. 5109 participants responded to the health survey questionnaire (adjusted response 56%). Radiographs were obtained in 557 participants. The prevalence of ankle pain was 11.7% (10.8,12.6) and symptomatic, radiographic ankle OA grade≥2 was 3.4% (2.3, 4.5) (grade≥1: 8.8% (7.9,9.8); grade = 3: 1.9% (1.0,2.7). Prevalence was higher in females, younger adults (50-64 years) and those with routine/manual occupations.

CONCLUSION

No general population prevalence estimates of radiographic ankle OA were identified in the published literature. Our prevalence study found that ankle pain was common in community-dwelling older adults, whereas moderate to severe symptomatic, radiographic ankle OA occurred less frequently. Further investigations of the prevalence of ankle OA using more sensitive imaging modalities are warranted.

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.

Biomechanical Effects of Prefabricated Foot Orthoses and Rocker-Sole Footwear in Individuals With First Metatarsophalangeal Joint Osteoarthritis

Objective

To evaluate the effects of prefabricated foot orthoses and rocker‐sole footwear on spatiotemporal parameters, hip and knee kinematics, and plantar pressures in people with first metatarsophalangeal (MTP) joint osteoarthritis (OA). Methods. A total of 102 people with first MTP joint OA were randomly allocated to receive prefabricated foot orthoses or rocker‐sole footwear. The immediate biomechanical effects of the interventions (compared to usual footwear) were examined using a wearable sensor motion analysis system and an in‐shoe plantar pressure measurement system.

Results

Spatiotemporal/kinematic and plantar pressure data were available from 88 and 87 participants, respectively. The orthoses had minimal effect on spatiotemporal or kinematic parameters, while the rocker‐sole footwear resulted in reduced cadence, percentage of the gait cycle spent in stance phase, and sagittal plane hip range of motion. The orthoses increased peak pressure under the midfoot and lesser toes. Both interventions significantly reduced peak pressure under the first MTP joint, and the rocker‐sole shoes also reduced peak pressure under the second through fifth MTP joints and heel. When the effects of the orthoses and rocker‐sole shoes were directly compared, there was no difference in peak pressure under the hallux, first MTP joint, or heel; however, the rocker‐sole shoes exhibited lower peak pressure under the lesser toes, second through fifth MTP joints, and midfoot.

Conclusion

Prefabricated foot orthoses and rocker‐sole footwear are effective at reducing peak pressure under the first MTP joint in people with first MTP joint OA, but achieve this through different mechanisms. Further research is required to determine whether these biomechanical changes result in improvements in symptoms.

TUFT1, a novel candidate gene for metatarsophalangeal osteoarthritis, plays a role in chondrogenesis on a calcium-related pathway

Osteoarthritis (OA) is the most common degenerative joint disorder and genetic factors have been shown to have a significant role in its etiology. The first metatarsophalangeal joint (MTP I) is highly susceptible to development of OA due to repetitive mechanical stress during walking. We used whole exome sequencing to study genetic defect(s) predisposing to familial early-onset bilateral MTP I OA inherited in an autosomal dominant manner. A nonsynonymous single nucleotide variant rs41310883 (c.524C>T, p.Thr175Met) in TUFT1 gene was found to co-segregate perfectly with MTP I OA. The role of TUFT1 and the relevance of the identified variant in pathogenesis of MTP I OA were further assessed using functional in vitro analyses. The variant reduced TUFT1 mRNA and tuftelin protein expression in HEK293 cells. ATDC5 cells overexpressing wild type (wt) or mutant TUFT1 were cultured in calcifying conditions and chondrogenic differentiation was found to be inhibited in both cell populations, as indicated by decreased marker gene expression when compared with the empty vector control cells. Also, the formation of cartilage nodules was diminished in both TUFT1 overexpressing ATDC5 cell populations. At the end of the culturing period the calcium content of the extracellular matrix was significantly increased in cells overexpressing mutant TUFT1 compared to cells overexpressing wt TUFT1 and control cells, while the proteoglycan content was reduced. These data imply that overexpression of TUFT1 in ATDC5 inhibits chondrogenic differentiation, and the identified variant may contribute to the pathogenesis of OA by increasing calcification and reducing amount of proteoglycans in the articular cartilage extracellular matrix thus making cartilage susceptible for degeneration and osteophyte formation.

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.

Effect of Arthrocentesis on Symptomatic Osteoarthritis of the Temporomandibular Joint and Analysis of the Effect of Preoperative Clinical and Radiologic Features

PURPOSE

To evaluate the long-term outcome of arthrocentesis in patients with symptomatic temporomandibular joint (TMJ) osteoarthritis that was unresponsive to nonsurgical interventions.

MATERIALS AND METHODS

Seventy-nine patients (83 joints) with symptomatic TMJ osteoarthritis that had not responded to nonsurgical interventions and who underwent arthrocentesis were included in this study. Demographic, clinical, and radiologic data, including assessment of pain, dysfunction, improvement, and satisfaction, and maximal mouth opening were analyzed.

RESULTS

The analysis included 67 female patients (84.8%) and 12 male patients (15.2%), 13 to 70 years old, who were followed for 56.9 ± 6.7 months. Sixty-four (81%) reacted favorably to arthrocentesis. For these patients, maximal mouth opening increased from 26.3 ± 0.8 to 39.24 ± 0.9 mm (P < .001). Pain and dysfunction scores decreased from 6.92 ± 0.2 to 2.36 ± 0.3 (P < .001) and from 7.37 ± 0.2 to 2.24 ± 0.4 (P < .001), respectively. Overall score for patient satisfaction with arthrocentesis was 8.78 ± 0.3. The procedure had no lasting complications. Remarkably, the severity of preoperative pain, dysfunction, and range of motion and of radiographic changes did not correlate with the outcome of arthrocentesis. The severity of preoperative or postoperative signs and symptoms was not correlated with the severity of radiographic changes.

CONCLUSIONS

For most patients, arthrocentesis offers long-term favorable outcomes for symptomatic TMJ osteoarthritis that has not responded to nonsurgical treatments and otherwise would have required surgical arthroplasty. Severity of preoperative clinical and computerized tomographic findings is not predictive for the success of arthrocentesis. In addition, the lack of correlation between the clinical and radiologic findings negates the commonly used Wilkes classification, which presumes that the clinical signs and symptoms deteriorate together with radiologic changes.

Post-traumatic subtalar osteoarthritis: which grading system should we use?

PURPOSE

To assess and compare post-traumatic osteoarthritis following intra-articular calcaneal fractures, one must have a reliable grading system that consistently grades the post-traumatic changes of the joint. A reliable grading system aids in the communication between treating physicians and improves the interpretation of research. To date, there is no consensus on what grading system to use in the evaluation of post-traumatic subtalar osteoarthritis. The objective of this study was to determine and compare the inter- and intra-rater reliability of two grading systems for post-traumatic subtalar osteoarthritis.

METHODS

Four observers evaluated 50 calcaneal fractures at least one year after trauma on conventional oblique lateral, internally and externally rotated views, and graded post-traumatic subtalar osteoarthritis using the Kellgren and Lawrence Grading Scale (KLGS) and the Paley Grading System (PGS). Inter- and intra-rater reliability were calculated and compared.

RESULTS

The inter-rater reliability showed an intra-class correlation (ICC) of 0.54 (95 % CI 0.40-0.67) for the KLGS and an ICC of 0.41 (95 % CI 0.26 - 0.57) for the PGS. This difference was not statistically significant. The intra-rater reliability showed a mean weighted kappa of 0.62 for both the KLGS and the PGS.

CONCLUSION

There is no statistically significant difference in reliability between the Kellgren and Lawrence Grading System (KLGS) and the Paley Grading System (PGS). The PGS allows for an easy two-step approach making it easy for everyday clinical purposes. For research purposes however, the more detailed and widely used KLGS seems preferable.

Effectiveness of Foot Orthoses Versus Rocker-Sole Footwear for First Metatarsophalangeal Joint Osteoarthritis: Randomized Trial

OBJECTIVE

To compare the effectiveness of prefabricated foot orthoses to rocker-sole footwear in reducing foot pain in people with first metatarsophalangeal (MTP) joint osteoarthritis (OA).

METHODS

Participants (n = 102) with first MTP joint OA were randomly allocated to receive individualized, prefabricated foot orthoses or rocker-sole footwear. The primary outcome measure was the pain subscale on the Foot Health Status Questionnaire (FHSQ) at 12 weeks. Secondary outcome measures included the function, footwear, and general foot health subscales of the FHSQ; the Foot Function Index; severity of pain and stiffness at the first MTP joint; perception of global improvement; general health status; use of rescue medication and co-interventions to relieve pain; physical activity; and the frequency of self-reported adverse events.

RESULTS

The FHSQ pain subscale scores improved in both groups, but no statistically significant difference between the groups was observed (adjusted mean difference 2.05 points, 95% confidence interval [95% CI] -3.61, 7.71; P = 0.477). However, the footwear group exhibited lower adherence (mean ± SD total hours worn 287 ± 193 versus 448 ± 234; P < 0.001), were less likely to report global improvement in symptoms (39% versus 62%; relative risk [RR] 0.63, 95% CI 0.41, 0.99; P = 0.043), and were more likely to experience adverse events (39% versus 16%; RR 2.47, 95% CI 1.12, 5.44; P = 0.024) compared to the orthoses group.

CONCLUSION

Prefabricated foot orthoses and rocker-sole footwear are similarly effective at reducing foot pain in people with first MTP joint OA. However, prefabricated foot orthoses may be the intervention of choice due to greater adherence and fewer associated adverse events.

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.

The epidemiology of symptomatic midfoot osteoarthritis in community-dwelling older adults: cross-sectional findings from the Clinical Assessment Study of the Foot

Introduction

The foot is largely overlooked in calls for better characterisation of clinical phenotypes in osteoarthritis (OA). Yet the midfoot complex in particular has the potential to provide important insights into OA pathogenesis given its central role in lower limb load transmission and alignment. Its recent inclusion in radiographic atlases has paved the way for international studies. In this UK study, we provide the first comprehensive account of the descriptive epidemiology of symptomatic midfoot OA.

Methods

Participants aged ≥50 years registered with four general practices were recruited via a mailed health survey (n = 5109 responders) and research clinic (n = 560 responders). Symptomatic midfoot OA was defined as midfoot pain in the last 4 weeks, combined with radiographic OA in one or more joints (1st and 2nd cuneometatarsal, navicular first cuneiform and talonavicular joints) graded from weight-bearing dorso-plantar and lateral radiographs using a validated atlas. Prevalence estimates, overall and stratified by age, gender, and socio-economic class, were derived using multiple imputation and weighted logistic regression. Associations between symptomatic midfoot OA and current body mass index, previous injury, history of high-heeled footwear, nodal interphalangeal joint OA and patterns of comorbidity were estimated using binary logistic regression. Healthcare use was summarised.

Results

Symptomatic midfoot OA was present in 12.0 % (95 % CI: 10.9, 13.2) of the population aged over 50 years. Higher occurrence was observed in females, adults aged over 75 years, and those in intermediate/routine occupational classes. Obesity, previous foot/ankle injury, and pain in other weight-loaded joints, but not high-heeled footwear or nodal interphalangeal joint OA, were associated with increased risk of symptomatic midfoot OA. Persons with symptomatic midfoot OA were also more likely to report multiple non-musculoskeletal comorbidities, including diabetes. In the previous 12 months, the proportions consulting a general practitioner, physiotherapist or podiatrist/chiropodist about foot pain were 46.2 %, 18.5 % and 47.9 % respectively. A total of 64.7 % had used oral analgesia in the past month for foot pain (36.1 % paracetamol, 31.9 % mild/moderate opioids, 27.7 % NSAIDs).

Conclusions

Our study confirms that symptomatic OA frequently affects the midfoot. The patterns of associations are interpreted as being largely consistent with the role of mechanical factors in its pathogenesis.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-015-0693-3) contains supplementary material, which is available to authorized users.

Case study: a case of debilitating gout in the 1st metatarsophalangeal joint

Gout is a painful arthritic condition that affects many people worldwide. The disease has been associated with hyperuricaemia and life style risk factors such as obesity, alcohol intake, meat and seafood consumption. We present a case of a 67-year-old male with a history of gout, who attended the clinic with a painful 1st metatarsophalangeal joint, which had progressively worsened in pain, mobility and deformity in the last 20 years. Although lifestyle changes had been advised by the GP some years earlier such as a low purine based diet, management had only consisted of NSAID's, which had not significantly improved symptoms. Surgical excision of chalky white material from around the 1st metatarsophalangeal joint rendered the patient symptom free with increased mobility after 6 weeks. Histopathology confirmed the excised tissue as gouty tophus. Following this, the patient was placed on allopurinol, a xanthine oxidase inhibitor to prevent recurrent attacks. This case study highlights the importance of early recognition and prophylactic management in gout sufferers. In joints where the disease process is well-established surgical excision of the gouty tophus may help mitigate further disease progression, and restore quality of life to individuals.

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.

Demographic and clinical factors associated with radiographic severity of first metatarsophalangeal joint osteoarthritis: cross-sectional findings from the Clinical Assessment Study of the Foot

OBJECTIVE

To explore demographic and clinical factors associated with radiographic severity of first metatarsophalangeal joint osteoarthritis (OA) (First MTPJ OA).

DESIGN

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 a clinical assessment and weight-bearing dorso-plantar and lateral radiographs of both feet. Radiographic first MTPJ OA in the most severely affected foot was graded into four categories using a validated atlas. Differences in selected demographic and clinical factors were explored across the four radiographic severity subgroups using analysis of variance (ANOVA) and ordinal regression.

RESULTS

Clinical and radiographic data were available from 517 participants, categorised as having no (n = 105), mild (n = 228), moderate (n = 122) or severe (n = 62) first MTPJ OA. Increased radiographic severity was associated with older age and lower educational attainment. After adjusting for age, increased radiographic first MTPJ OA severity was significantly associated with an increased prevalence of dorsal hallux and first MTPJ pain, hallux valgus, first interphalangeal joint (IPJ) hyperextension, keratotic lesions on the dorsal aspect of the hallux and first MTPJ, decreased first MTPJ dorsiflexion, ankle/subtalar joint eversion and ankle joint dorsiflexion range of motion, and a trend towards a more pronated foot posture.

CONCLUSIONS

This cross-sectional study has identified several dose-response associations between radiographic severity of first MTPJ OA and a range of demographic and clinical factors. These findings highlight the progressive nature of first MTPJ OA and provide insights into the spectrum of presentation of the condition in clinical practice.

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.

Review of the evidence: surgical management of 4th and 5th tarsometatarsal joint osteoarthritis

Osteoarthritis of the lateral tarsometatarsal joints is less common than that which is seen in the 1st-3rd tarsometatarsal joints. Despite a suspected increase in incidence of tarsometatarsal arthritis and consequently the burden of disability and economic impact, guidelines for treatment and decision making remain scarce. When conservative treatment fails, lateral column osteoarthritis can severely limit a patient's mobility, lifestyle, and present a difficult management problem for the foot and ankle specialist. Evidence for the surgical techniques used in treatment of lateral column osteoarthritis is limited and sporadic within the literature. This article aims to summarise and compare the evidence for these surgical management options. This article looks at aetiology and epidemiology, with a summary of the biomechanics of the region and a comprehensive review of the literature regarding surgical treatment options.

An analysis of the use of the Kellgren and Lawrence grading system to evaluate peritalar arthritis following total ankle arthroplasty

BACKGROUND

The Kellgren and Lawrence grading system (KLGS) has been used throughout the literature for the radiographic staging of osteoarthritis (OA) of the peritalar joints. Despite its widespread use, the KLGS has never been validated for use in this clinical circumstance. The purpose of this study was to determine the inter- and intrarater reliability of the KLGS in the assessment of radiographic progression of OA in the peritalar joints following total ankle replacement (TAR).

METHODS

One hundred twenty pre- and minimum 5-year postoperative weight-bearing lateral radiographs following 60 consecutive cases of TAR were utilized. Each individual film was considered separately for the purposes of this study. Of those films, 93 and 98 were found to have adequate visualization of the subtalar (STJ) and talonavicular (TNJ) joints, respectively. Three qualified reviewers graded the films according to the KLGS on 2 separate occasions, with 1 month separating the 2 readings. The results were analyzed for intra- and interobserver reliability. The degree of agreement was analyzed using the weighted kappa (κ(w)) statistic, Fleiss's kappa (Fleiss's κ), and percentage agreement

RESULTS

Interrater agreements were moderate (κ(w) = 0.37 ± 0.06; Fleiss's κ = 0.21 ± 0.03) for the STJ to fair (κ(w) = 0.43 ± 0.06; Fleiss's κ = 0.25 ± 0.03) for the TNJ. Intrarater agreements for the STJ were moderate (mean κ(w) = 0.43 ± 0.07) and moderate for the TNJ as well (mean κ(w) = 0.46 ± 0.07). The reliability of the KLGS, although not originally designed for use in the setting of inflammatory arthropathy, was not notably affected when being used to grade inflammatory versus noninflammatory arthropathy.

CONCLUSIONS

The KLGS is likely not a reliable tool for grading the degree of OA present in the peritalar joints prior to treatment and following TAR for research purposes. Using the KLGS in the setting of inflammatory arthritis versus OA did not produce any notable differences in the observed reliability. It is important to remember this has not been assessed in the clinical environment. Further work is required to determine the optimal method for assessment of peritalar OA.

LEVEL OF EVIDENCE

Level II, prospective comparative study.

The population prevalence of foot and ankle pain in middle and old age: a systematic review

A systematic review and meta-analysis of population-based epidemiological studies was undertaken to determine the prevalence of foot and ankle pain in middle and old age. Searches were conducted in the following electronic databases from inception to October 2010: PubMed, EMBASE, AMED, CINAHL, Cochrane, PEDro, and SportDiscus. Full-text English language articles were included if they used population sample frames, cross-sectional design or analysis, and reported prevalence estimates for foot and/or ankle pain in adults aged 45 years and over. Thirty-four articles from 31 studies involving 75,505 participants provided 529 prevalence estimates based on different case definitions and population strata. Random-effects meta-analyses of studies with comparable case definitions provided pooled prevalence estimates, for frequent foot pain of 24% (95% confidence interval 22-25%; n=3; I(2)=46%) and for frequent ankle pain of 15% (95% confidence interval 13-16%; n=2; I(2)=0). Small sample sizes and low response rates in some studies, together with heterogeneous case definitions, limit confident conclusions on the distribution, subtypes, and impact of foot/ankle pain. Narrative synthesis of evidence from existing studies suggested preponderance in females, an age-related increase in prevalence in women but not men, that the toes/forefoot were the most common anatomical sites of pain, and that moderate disability in an aspect of daily life was reported by two-thirds of cases. This review provides estimates of the community burden of foot and ankle pain in middle and old age. By outlining the scale of this clinical problem, these findings can be used to inform health care planning and provision.

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.

The clinical assessment study of the foot (CASF): study protocol for a prospective observational study of foot pain and foot osteoarthritis in the general population

BACKGROUND

Symptomatic osteoarthritis (OA) affects approximately 10% of adults aged over 60 years. The foot joint complex is commonly affected by OA, yet there is relatively little research into OA of the foot, compared with other frequently affected sites such as the knee and hand. Existing epidemiological studies of foot OA have focussed predominantly on the first metatarsophalangeal joint at the expense of other joints. This three-year prospective population-based observational cohort study will describe the prevalence of symptomatic radiographic foot OA, relate its occurrence to symptoms, examination findings and life-style-factors, describe the natural history of foot OA, and examine how it presents to, and is diagnosed and managed in primary care.

METHODS

All adults aged 50 years and over registered with four general practices in North Staffordshire, UK, will be invited to participate in a postal Health Survey questionnaire. Respondents to the questionnaire who indicate that they have experienced foot pain in the preceding twelve months will be invited to attend a research clinic for a detailed clinical assessment. This assessment will consist of: clinical interview; physical examination; digital photography of both feet and ankles; plain x-rays of both feet, ankles and hands; ultrasound examination of the plantar fascia; anthropometric measurement; and a further self-complete questionnaire. Follow-up will be undertaken in consenting participants by postal questionnaire at 18 months (clinic attenders only) and three years (clinic attenders and survey participants), and also by review of medical records.

DISCUSSION

This three-year prospective epidemiological study will combine survey data, comprehensive clinical, x-ray and ultrasound assessment, and review of primary care records to identify radiographic phenotypes of foot OA in a population of community-dwelling older adults, and describe their impact on symptoms, function and clinical examination findings, and their presentation, diagnosis and management in primary care.

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.

Revisiting the pathogenesis of podagra: why does gout target the foot?

This invited paper provides a summary of a keynote lecture delivered at the 2011 Australasian Podiatry Conference. Gout is the most prevalent inflammatory arthropathy. It displays a striking predilection to affect the first metatarsophalangeal joint as well as joints within the mid-foot and ankle. A number of factors are known to reduce urate solubility and enhance nucleation of monosodium urate crystals including decreased temperature, lower pH and physical shock, all of which may be particularly relevant to crystal deposition in the foot. An association has also been proposed between monosodium urate crystal deposition and osteoarthritis, which also targets the first metatarsophalangeal joint. Cadaveric, clinical and radiographic studies indicate that monosodium urate crystals more readily deposit in osteoarthritic cartilage. Transient intra-articular hyperuricaemia and precipitation of monosodium urate crystals is thought to follow overnight resolution of synovial effusion within the osteoarthritic first metatarsophalangeal joint. The proclivity of gout for the first metatarsophalangeal joint is likely to be multi-factorial in origin, arising from the unique combination of the susceptibility of the joint to osteoarthritis and other determinants of urate solubility and crystal nucleation such as temperature and minor physical trauma which are particularly relevant to the foot.