Significant functional impairment and disability in individuals with psoriatic arthritis and Achilles tendon pain: a cross-sectional observational study.

The Achilles tendon (AT) insertion is the most common site of enthesitis in psoriatic arthritis (PsA). The structure and function of the AT in PsA, and the prevalence of mid-portion pathology, is unknown. To compare the structure and function of the AT in people with PsA with self-reported AT pain (PsA + AT), PsA without self-reported AT pain (PsA-AT) and healthy controls. A cross-sectional, observational study was conducted. The ATs were assessed by clinical and US examination (B-mode and Power Doppler), performance-based testing (bilateral heel raise test (HRT) and 10 m walk test), and patient-reported outcome measures (PROMs) (including the Victorian Institute of Sport Assessment-Achilles [VISA-A]). Between-group differences were described using descriptive statistics, Chi-squared testing, parametric (1-way ANOVA) and non-parametric (Mann-Whitney or Kruskal-Wallis) testing. 22 PsA (11 per group) and 11 healthy control participants who were comparable in terms of sex, age, and BMI (PsA-AT = longer PsA disease duration) were recruited. VISA-A scores were significantly worse in the PsA + AT group compared to the PsA-AT group and healthy controls (p < 0.001). Inflammatory US features were significantly more prevalent in the PsA + AT group (p < 0.001). Mid-portion AT pathology was observed in the PsA + AT group, irrespective of entheseal disease. Clinical examination alone missed 5/7 cases of 'active' US-confirmed AT enthesitis. AT functional deficits were significant in the PsA + AT group and both PsA groups had lower HRT repetition rates and walked slower compared to healthy controls. Less than 1/3 of the PsA + AT group had received podiatry or physiotherapy care. Significant differences in the structure and function of the AT in PsA were noted. Despite management in line with current guidance, AT pain appears to persist and can result in severe functional impairment.

EFAS Score - Validation of Danish Version by the Score Committee of the European Foot and Ankle Society (EFAS).

BACKGROUND: The Score Committee of the European Foot and Ankle Society (EFAS) developed, validated, and published the EFAS Score in 13 languages. Currently, the Danish version completed data acquisition and underwent further validation. METHODS: The data were collected pre-operatively and post-operatively at a minimum follow-up of 3 months and mean follow-up of 6 months. Item reduction, scale exploration, confirmatory analyses and responsiveness were executed using classical test theory and item response theory. RESULTS: The internal consistency was confirmed in the Danish version (Cronbach's Alpha 0.88). The Standard Error of Measurement (SEM) was 0.31 and is similar to other language versions. Between baseline and follow-up, 77.2% of patients showed an improvement on their EFAS score, with adequate responsiveness (effect size 1.05). CONCLUSIONS: The Danish EFAS Score version was successfully validated in patients with a wide variety of foot and ankle pathologies. All score versions are freely available at www.efas.net.

Assessing the construct validity of musculoskeletal ultrasound and the rheumatoid arthritis foot disease activity index (RADAI-F5) for managing rheumatoid foot disease.

Objective: The RA foot disease activity index (RADAI-F5) is a valid, reliable and clinically feasible patient-reported outcome measure (PROM) for the measurement of RA foot disease activity. Further validation of the RADAI-F5 against musculoskeletal ultrasonography (MSUS) for foot disease activity is necessary before clinical implementation. The aim of this study was to examine the construct validity of the RADAI-F5 in relationship to MSUS and clinical examination. Methods: Participants with RA completed the RADAI-F5. MSUS was used to evaluate disease activity (synovial hypertrophy/synovitis/tenosynovitis/bursitis) and joint damage (erosion) using greyscale (GS) and power Doppler (PD) at 16 regions in each foot, including joints and soft tissues. These same regions were examined clinically for swelling and tenderness. The construct validity of the RADAI-F5 was assessed using correlation coefficients and a priori-specified hypotheses for the strength of associations. Results: Of 60 participants, 48 were female, with a mean (s.d.) age of 62.6 (9.96) years and median disease duration of 15.49 (interquartile range 6-20.5) years. Theoretically consistent associations confirming construct validity [95% CI] were observed between the RADAI-F5 and MSUS GS (0.76 [0.57, 0.82]; strong), MSUS PD (0.55 [0.35, 0.71]; moderate), MSUS-detected erosions (0.41 [0.18, 0.61]; moderate), clinical tenderness (0.52 [0.31, 0.68]; moderate) and clinical swelling (0.36 [0.13, 0.55]; weak). Conclusion: Moderate to strong correlations between RADAI-F5 and MSUS demonstrate the good measurement properties of this instrument. With greater confidence in the utility of the RADAI-F5, clinical use of this new instrument as an adjunct to the disease activity score for 28 joints (DAS-28) could help to identify RA patients at risk for poor functional and radiological outcomes.

Suitability of the animated activity questionnaire for use as computer adaptive test: establishing the AAQ-CAT.

PURPOSE: The animated activity questionnaire (AAQ) is a computer-based measure of activity limitations. To answer a question, patients choose the animation of a person performing an activity that matches their own level of limitation. The AAQ has not yet been tested for suitability to be applied as computer-adaptive test (CAT). Thus, the objective of this study was to develop and evaluate an AAQ-based CAT to facilitate the application of the AAQ in daily clinical care. METHODS: Patients (n = 1408) with hip/knee osteoarthritis from Brazil, Denmark, France, The Netherlands, Norway, Spain, and the UK responded to all 17 AAQ items. Assumptions of item-response theory (IRT) modelling were investigated. To establish item parameters for the CAT, a graded response model was estimated. To evaluate the performance of post-hoc simulated AAQ-based CATs, precision, test length, and construct validity (correlations with well-established measures of activity limitations) were evaluated. RESULTS: Unidimensionality (CFI = 0.95), measurement invariance (R2-change < 2%), and IRT item fit (S-X2 p > .003) of the AAQ were supported. Performing simulated CATs, the mean test length was more than halved (≤ 8 items), while the range of precise measurement (standard error ≤ 0.3) was comparable to the full AAQ. The correlations between original AAQ scores and three AAQ-CAT versions were ≥ 0.95. Correlations of AAQ-CAT scores with patient-reported and performance measures of activity limitations were ≥ 0.60. CONCLUSION: The almost non-verbal AAQ-CAT is an innovative and efficient tool in patients with hip/knee osteoarthritis from various countries, measuring activity limitations with lower respondent burden, but similar precision and construct validity compared to the full AAQ.

EFAS Score-Validation of Spanish and Estonian Versions by the Score Committee of the European Foot and Ankle Society (EFAS).

BACKGROUND: The Score Committee of the European Foot and Ankle Society (EFAS) developed, validated, and published the EFAS Score in 11 languages (Dutch, English, German, Finnish, French, Italian, Polish, Portuguese, Persian, Swedish, Turkish). From other languages under validation, the Spanish and Estonian versions completed data acquisition and underwent further validation. METHODS: The EFAS Score was developed and validated in three stages: 1) item (question) identification (completed during the initial validation study), 2) item reduction and scale exploration (completed during the initial validation study), 3) confirmatory analyses and responsiveness of the Spanish and Estonian versions (completed during the initial validation study in seven other languages). The data were collected pre-operatively and post-operatively at a minimum follow-up of 3 months and mean follow-up of 6 months. Item reduction, scale exploration, confirmatory analyses and responsiveness were executed using classical test theory and item response theory. RESULTS: The internal consistency of the scale was confirmed in the Spanish and Estonian versions (Cronbach's Alpha>0.8). Responsiveness was good, with moderate to large effect sizes in both languages, and evidence of a statistically significant positive association between the EFAS Score and patient-reported improvement. CONCLUSIONS: The Spanish and Estonian EFAS Score versions were successfully validated in orthopaedic ankle and foot surgery patients, with a wide variety of foot and ankle pathologies. All score versions are freely available at www.efas.net.

The challenges of measuring physical activity and sedentary behaviour in people with rheumatoid arthritis.

The importance of sufficient moderate-to-vigorous physical activity as a key component of a healthy lifestyle is well established, as are the health risks associated with high levels of sedentary behaviour. However, many people with RA do not undertake sufficient physical activity and are highly sedentary. To start addressing this, it is important to be able to carry out an adequate assessment of the physical activity levels of individual people in order that adequate steps can be taken to promote and improve healthy lifestyles. Different methods are available to measure different aspects of physical activity in different settings. In controlled laboratory environments, respiratory gas analysis can measure the energy expenditure of different activities accurately. In free-living environments, the doubly labelled water method is the gold standard for identifying total energy expenditure over a prolonged period of time (>10 days). To assess patterns of physical activity and sedentary behaviour in daily life, objective methods with body-worn activity monitors using accelerometry are superior to self-reported questionnaire- or diary-based methods.

Barriers and facilitators to physical activity in people with an inflammatory joint disease: a mixed methods study.

BACKGROUND: Physical activity has been shown to be of great benefit to people with an inflammatory joint disease (IJD), however people with an IJD have been shown to be very inactive compared to the general population. The aims of this study were to explore 1) whether the transition from a National Health Service (NHS)-run exercise programme into exercising in the community could be achieved successfully; and 2) the barriers and facilitators during the transition period. METHODS: This study adopted a complementary mixed-methods study design including a qualitative approach using focus groups and a prospective cohort study. Descriptive statistics were used to summarise the cohort study data. All variables were assessed for normality of distribution using the Sharpiro-Wilk test. Paired t-tests or Wilcoxon tests were undertaken for two consecutive assessment timepoints; one-way repeated measures ANOVAs or Friedman's tests for three consecutive assessment timepoints. Micro-interlocutor analysis was used to analyse the focus group data. Areas of congruence and incongruence were explored by confirming the statistical results against the qualitative results. The adapted ecological model of the determinants of physical activity was then used as a framework to describe the findings. RESULTS: A successful transition was defined as still exercising in the community 6-months post discharge from the NHS-run Inflammatory Arthritis Exercise Programme. This was self-reported to be 90% of the cohort. An individual barrier to physical activity in people with an IJD was found to be the unpredictable nature of their condition. Other barriers and facilitators found were similar to those found in the general population such as recreation facilities, locations, transportation and cost. Other facilitators were similar to those found in people living with other chronic long-term conditions such as the importance of peer support. CONCLUSIONS: 90% of the cohort data were defined as a successful transition. People with an IJD have similar barriers and facilitators to exercise as the general population and those living with other chronic long-term conditions. A barrier which appears to be unique to this population group is that of the unpredictable nature of their condition which needs to be considered whenever tailoring any intervention.

Biomarkers associated with lower limb muscle function in individuals with sarcopenia: a systematic review.

Lower limb muscle dysfunction is a key driver for impaired physical capacity and frailty status, both characteristics of sarcopenia. Sarcopenia is the key pathway between frailty and disability. Identifying biological markers for early diagnosis, treatment, and prevention may be key to early intervention and prevention of disability particularly mobility issues. To identify biological markers associated with lower limb muscle (dys)function in adults with sarcopenia, a systematic literature search was conducted in AMED, CINAHL, Cochrane Library, EMBASE, Medline, PubMed, Scopus, SPORTDiscus, and Web of Science databases from inception to 17 November 2021. Title, abstract, and full-text screening, data extraction, and methodological quality assessment were performed by two reviewers independently and verified by a third reviewer. Depending on available data, associations are reported as either Pearson's correlations, regression R2 or partial R2 , P value, and sample size (n). Twenty eligible studies including 3306 participants were included (females: 79%, males: 15%, unreported: 6%; mean age ranged from 53 to 92 years) with 36% in a distinct sarcopenic subgroup (females: 73%, males: 19%, unreported: 8%; mean age range 55-92 years). A total of 119 biomarkers were reported, categorized into: genetic and microRNAs (n = 64), oxidative stress (n = 10), energy metabolism (n = 18), inflammation (n = 7), enzyme (n = 4), hormone (n = 7), bone (n = 3), vitamin (n = 2), and cytokine (n = 4) markers) and seven lower limb muscle measures predominately focused on strength. Seven studies reported associations between lower limb muscle measures including (e.g. power, force, and torque) and biomarkers. In individuals with sarcopenia, muscle strength was positively associated with free testosterone (r = 0.40, P = 0.01; n = 46). In analysis with combined sarcopenic and non-sarcopenic individuals, muscle strength was positively associated with combined genetic and methylation score (partial R2  = 0.122, P = 0.03; n = 48) and negatively associated with sarcopenia-driven methylation score (partial R2  = 0.401, P < 0.01; n = 48). Biomarkers related to genetics (R2  = 0.001-0.014, partial R2  = 0.013-0.122, P > 0.05; n = 48), oxidative stress (r = 0.061, P > 0.05; n ≥ 77), hormone (r = 0.01, ρ = 0.052 p > 0.05, n ≥ 46) and combined protein, oxidative stress, muscle performance, and hormones (R2  = 22.0, P > 0.05; n ≥ 82) did not report significant associations with lower limb muscle strength. Several biomarkers demonstrated associations with lower limb muscle dysfunction. The current literature remains difficult to draw clear conclusions on the relationship between biomarkers and lower limb muscle dysfunction in adults with sarcopenia. Heterogeneity of biomarkers and lower limb muscle function precluded direct comparison. Use of international classification of sarcopenia and a set of core standardized outcome measures should be adopted to aid future investigation and recommendations to be made.

EFAS Score - Validation of Portuguese Version by the Score Committee of the European Foot and Ankle Society (EFAS).

BACKGROUND: The Score Committee of the European Foot and Ankle Society (EFAS) developed, validated, and published the EFAS Score in ten languages (English, German, French, Italian, Polish, Dutch, Swedish, Finnish, Turkish, Portuguese). From other languages under validation, the Portuguese version completed data acquisition and underwent further validation. METHODS: The Portuguese version of the EFAS Score was developed and validated in three stages: 1) item (question) identification (completed during initial validation study), 2) item reduction and scale exploration (completed during initial validation study), 3) confirmatory analyses and responsiveness of Portuguese version (completed during initial validation study in nine other languages). The data were collected pre-operatively and post-operatively at a minimum follow-up of 3 months and mean follow-up of 6 months. Item reduction, scale exploration, confirmatory analyses and responsiveness were executed using classical test theory and item response theory. RESULTS: The internal consistency was confirmed in the Portuguese version (Cronbach's Alpha 0.84). The Standard Error of Measurement (SEM) was 0.27 and is similar to other language versions. Between baseline and follow-up, 69.4% of patients showed an improvement on their EFAS score, with adequate responsiveness (effect size 0.64). CONCLUSIONS: The Portuguese EFAS Score version was successfully validated in patients with a wide variety of foot and ankle pathologies. All score versions are freely available at www.efas.net.

Gait rehabilitation for foot and ankle impairments in early rheumatoid arthritis: a feasibility study of a new gait rehabilitation programme (GREAT Strides).

BACKGROUND: Foot impairments in early rheumatoid arthritis are common and lead to progressive deterioration of lower limb function. A gait rehabilitation programme underpinned by psychological techniques to improve adherence, may preserve gait and lower limb function. This study evaluated the feasibility of a novel gait rehabilitation intervention (GREAT Strides) and a future trial. METHODS: This was a mixed methods feasibility study with embedded qualitative components. People with early (< 2 years) rheumatoid arthritis (RA) and foot pain were eligible. Intervention acceptability was evaluated using a questionnaire. Adherence was evaluated using the Exercise Adherence Rating Scale (EARS). Safety was monitored using case report forms. Participants and therapists were interviewed to explore intervention acceptability. Deductive thematic analysis was applied using the Theoretical Framework of Acceptability. For fidelity, audio recordings of interventions sessions were assessed using the Motivational Interviewing Treatment Integrity (MITI) scale. Measurement properties of four candidate primary outcomes, rates of recruitment, attrition, and data completeness were evaluated. RESULTS: Thirty-five participants (68.6% female) with median age (inter-quartile range [IQR]) 60.1 [49.4-68.4] years and disease duration 9.1 [4.0-16.2] months), were recruited and 23 (65.7%) completed 12-week follow-up. Intervention acceptability was excellent; 21/23 were confident that it could help and would recommend it; 22/23 indicated it made sense to them. Adherence was good, with a median [IQR] EARS score of 17/24 [12.5-22.5]. One serious adverse event that was unrelated to the study was reported. Twelve participants' and 9 therapists' interviews confirmed intervention acceptability, identified perceptions of benefit, but also highlighted some barriers to completion. Mean MITI scores for relational (4.38) and technical (4.19) aspects of motivational interviewing demonstrated good fidelity. The Foot Function Index disability subscale performed best in terms of theoretical consistency and was deemed most practical. CONCLUSION: GREAT Strides was viewed as acceptable by patients and therapists, and we observed high intervention fidelity, good patient adherence, and no safety concerns. A future trial to test the additional benefit of GREAT Strides to usual care will benefit from amended eligibility criteria, refinement of the intervention and strategies to ensure higher follow-up rates. The Foot Function Index disability subscale was identified as the primary outcome for the future trial. TRIAL REGISTRATION: ISRCTN14277030.

Patients' and clinicians' perspectives on the clinical utility of the Rheumatoid Arthritis Foot Disease Activity Index.

Although patient-reported outcome measures (PROMs) are recommended in clinical practice, their application in routine care is limited. The Rheumatoid Arthritis Foot Disease Activity Index (RADAI-F5) is a validated PROM for assessing foot disease in rheumatoid arthritis (RA). To explore patient and clinician opinions and perceptions of the clinical utility of the Rheumatoid Arthritis Foot Disease Activity Index (RADAI-F5), eight RA patients and eight clinicians routinely involved in the management of RA patients participated in one semi-structured remote video-based interview. They provided their perspectives on the barriers and facilitators to clinical implementation of the RADAI-F5. Three global themes were identified; 'Feet are a priority' as the impact of RA on the feet negatively impacted upon patient quality of life. The second theme was 'Need for a clinically feasible foot PROM' as participants recognised the current lack of a clinically feasible tool to determine RA foot disease. The third global theme of 'Implementation' was drawn together to form two subordinate themes: 'Facilitators to RADAI-F5 implementation' as the tool can promote communication, guide management, help screen foot symptoms, monitor foot disease status and treatments, and promote patient education and; 'Barriers to RADAI-F5 implementation' as there were associated practical difficulties, including lack of appointment time, administrative burdens, IT barriers and preference for further RADAI-F5 validation using imaging. The RADAI-F5 has significant potential as a clinical tool to aid foot disease management. However, implementation challenges must be overcome before broad adoption in rheumatology clinics.

The role of perceived organisational justice in the experience of pain among male and female employees.

This study examined the association of organisational justice with pain among employees of a large organisation. Employees (n = 1829) completed measures of pain, fair pay, organisational justice, job satisfaction and stress. Logistic regression analyses found that organisational justice was unrelated to pain among women, but men with higher perceptions of fair pay were more likely to report chronic pain as were men with lower perceptions of distributive justice. This is the first study indicating that fair pay and distributive justice are both unique predictors of chronic pain in men. The findings have implications for supporting employees with chronic pain.

Physical Activity and Sedentary Behavior in People With Inflammatory Joint Disease: A Cross-Sectional Study.

OBJECTIVE: To determine whether patients with inflammatory joint disease (IJD) meet current guidelines on physical activity, and to determine which factors influence physical activity levels and sedentary behavior (SB) in patients with IJD. METHODS: This was a cross-sectional study of 137 patients with a medical diagnosis of an IJD prior to commencing an NHS-run inflammatory arthritis exercise program. Physical activity and SB were measured objectively using a thigh-worn physical activity monitor for 7 consecutive days. Activity levels were subdivided into low physical activity (LPA) and moderate-to-vigorous physical activity (MVPA). First, activity levels were analyzed against current guidelines of 150 minutes of MVPA per week. Second, time spent in SB, LPA, and MVPA was analyzed against possible determinants. RESULTS: In total, 29% of patients with IJD met current physical activity guidelines. Patients on average spent 10 hours per day in SB. Poor physical fitness measured by the 6-minute walk test was the only significant predictor (P = 0.019) of high SB (R2  = 4.7%). Attending an exercise facility in the community (P = 0.034) and low role limitations due to physical health (P = 0.008) predicted high levels of LPA, following a backward multiple regression (R2  = 8.0%). Low role limitations due to emotional problems (P = 0.031), higher physical fitness (P = 0.002), and healthier exercise attitudes and beliefs (P = 0.021) predicted meeting current physical activity guidelines, following a backward conditional logistic regression, explaining between 22.2% and 31.7% of variance. CONCLUSION: Patients with IJD are inactive and spent much time in SB. Good general health predicts high activity levels. No disease-specific factors were found to determine SB, LPA, or MVPA.

Ultrasound features of Achilles enthesitis in psoriatic arthritis: a systematic review.

OBJECTIVES: The objectives were to evaluate the methodological and reporting quality of ultrasound (US) studies of Achilles enthesitis in people with psoriatic arthritis (PsA), to identify the definitions and scoring systems adopted and to estimate the prevalence of ultrasound features of Achilles enthesitis in this population. METHODS: A systematic literature review was conducted using the AMED, CINAHL, MEDLINE, ProQuest and Web of Science databases. Eligible studies had to measure US features of Achilles enthesitis in people with PsA. Methodological quality was assessed using a modified Downs and Black Quality Index tool. US protocol reporting was assessed using a checklist informed by the European League Against Rheumatism (EULAR) recommendations for the reporting of US studies in rheumatic and musculoskeletal diseases. RESULTS: Fifteen studies were included. One study was scored as high methodological quality, 9 as moderate and 5 as low. Significant heterogeneity was observed in the prevalence, descriptions, scoring of features and quality of US protocol reporting. Prevalence estimates (% of entheses) reported included hypoechogenicity [mean 5.9% (s.d. 0.9)], increased thickness [mean 22.1% (s.d. 12.2)], erosions [mean 3.3% (s.d. 2.5)], calcifications [mean 42.6% (s.d. 15.6)], enthesophytes [mean 41.3% (s.d. 15.6)] and Doppler signal [mean 11.8% (s.d. 10.1)]. CONCLUSIONS: The review highlighted significant variations in prevalence figures that could potentially be explained by the range of definitions and scoring criteria available, but also due to the inconsistent reporting of US protocols. Uptake of the EULAR recommendations and using the latest definitions and validated scoring criteria would allow for a better understanding of the frequency and severity of individual features of pathology.

EFAS Score -Validation of Persian Version by the Score Committee of the European Foot and Ankle Society (EFAS).

BACKGROUND: The Score Committee of the European Foot and Ankle Society (EFAS) developed, validated, and published the EFAS Score in nine European languages (English, German, French, Italian, Polish, Dutch, Swedish, Finnish, Turkish). From other languages under validation, the Persian version finished data acquisition and underwent further validation. METHODS: The Persian version of the EFAS Score was developed and validated in three stages: 1) item (question) identification (completed during initial validation study), 2) item reduction and scale exploration (completed during initial validation study), 3) confirmatory analyses and responsiveness of Persian version (completed during initial validation study in nine other languages). The data were collected pre-operatively and post-operatively at a minimum follow-up of 3 months and mean follow-up of 6 months. Item reduction, scale exploration, confirmatory analyses and responsiveness were executed using classical test theory and item response theory. RESULTS: The internal consistency was confirmed in the Persian version (Cronbach's Alpha 0.82). The Standard Error of Measurement (SEM) was 0.38 and is similar to other language versions. Between baseline and follow-up, 97% of patients showed an improvement on their EFAS score, with excellent responsiveness (effect size 1.93). CONCLUSIONS: The Persian EFAS Score version was successfully validated in patients with a wide variety of foot and ankle pathologies. All score versions are freely available at www.efas.co.

Factors associated with fatigue in hip and/or knee osteoarthritis: a systematic review and best evidence synthesis.

OBJECTIVE: The aim was systematically to identify and evaluate factors related to fatigue in individuals with hip and/or knee OA. METHODS: A systematic literature search was conducted using AMED, CINAHL, MEDLINE, ProQuest and Web of Science Core Collections databases. Inclusion criteria comprised cross-sectional, case-control or longitudinal studies on patients with a diagnosis of hip and/or knee OA that included self-reported fatigue measures. Study quality was assessed using the National Heart, Lung and Blood Institute quality appraisal tool, and factors were synthesized within a bio-behavioural framework. Study designs and quality were combined to determine current evidence levels using best evidence synthesis grading. The full review protocol is available from PROSPERO (PROSPERO 2019: CRD42019138571). RESULTS: Twenty-four studies were included, of which 19 were high, 4 moderate and 1 low quality. There was strong evidence of an association between poor self-reported physical function and high depressive symptoms with higher fatigue. Moderate evidence of an association was found between severe pain, high numbers of co-morbidities and low physical activity levels with higher fatigue. There was moderate or limited evidence of no association between most sociodemographic factors and radiographic OA severity with fatigue. CONCLUSION: Targets for fatigue management might include improving physical function, reducing depressive symptoms, pain and co-morbidities, and increasing physical activity levels. There is a need for more rigorous longitudinal studies to understand the causal effect of fatigue determinants within the hip and knee OA populations.

Foot characteristics and mechanics in individuals with knee osteoarthritis: systematic review and meta-analysis.

BACKGROUND: Foot characteristics and mechanics are hypothesized to affect aetiology of several lower extremity musculoskeletal conditions, including knee osteoarthritis (KOA). The purpose of this systematic review was to identify the foot characteristics and mechanics of individuals with KOA. METHODS: Five databases were searched to identify relevant studies on foot characteristics and mechanics in people with KOA. Meta-analyses were performed where common measures were found across included studies. Included studies were evaluated for data reporting quality using the STROBE (STrengthening the Reporting of OBservational studies in Epidemiology) checklist. RESULTS: Thirty-nine studies were included in this systematic review. Two studies reported participants with KOA had statistically significantly (P < 0.05) more pronated foot postures than those without. Meta-analyses for foot progression angle (FPA) and peak rearfoot eversion angle found no difference between those with and without KOA (FPA mean difference:-1.50 [95% confidence interval - 4.20-1.21]; peak rearfoot eversion mean difference: 0.71 [1.55-2.97]). CONCLUSION: A more pronated foot posture was noticed in those with KOA. However, it was not possible to establish a relationship between other foot characteristics or mechanics in people with KOA due to heterogeneity between the included study and limited number of studies with similar measurements. There is need for identifying common measurement techniques and reporting metrics when studying the foot in those with KOA.

Measuring Inflammatory Foot Disease in Rheumatoid Arthritis: Development and Validation of the Rheumatoid Arthritis Foot Disease Activity Index-5.

OBJECTIVE: Omission of foot joints from composite global disease activity indices may lead to underestimation of foot and overall disease in rheumatoid arthritis (RA) and under-treatment. The aim of this study was to evaluate the measurement properties of the Rheumatoid Arthritis Foot Disease Activity Index-5 (RADAI-F5), a newly developed patient-reported outcome measure for capturing foot disease activity in people with RA. METHODS: Participants with RA self-completed the RADAI-F5, modified Rheumatoid Arthritis Disease Activity Index (mRADAI-5), Foot Function Index (FFI), and Foot Impact Scale (FIS) impairment/footwear and activity/participation subscales. The 28-joint Disease Activity Score using the erythrocyte sedimentation rate (DAS28-ESR) was also recorded. Subgroups completed the RADAI-F5 at 1 week and 6 months. Psychometric properties, including construct, content and longitudinal validity, internal consistency, 1-week reproducibility, and responsiveness over 6 months were evaluated. RESULTS: Of 142 respondents, 103 were female, with a mean ± SD age of 55 ± 12.5 years and median RA disease duration of 10 (interquartile range 3.6-20.8) months. Theoretically consistent associations confirming construct validity were observed with mRADAI-5 (0.789 [95% confidence interval (95% CI) 0.73, 0.85]), FFI (0.713 [95% CI 0.62, 0.79]), FIS impairment/footwear (0.695 [95% CI 0.66, 0.82], P < 0.001), FIS activity/participation (0.478 [95% CI 0.37, 0.63], P < 0.001), and the DAS28-ESR (0.379 [95% CI 0.26, 0.57], P < 0.001). The RADAI-F5 demonstrated high internal consistency (Cronbach's α = 0.90) and good reproducibility (intraclass correlation coefficient = 0.868 [95% CI 0.80, 0.91], P < 0.001, smallest detectable change = 2.69). Content validity was confirmed, with 82% rating the instrument relevant and easy to understand. CONCLUSION: The RADAI-F5 is a valid, reliable, responsive, clinically feasible patient-reported outcome measure for measuring foot disease activity in RA.

Sex- and osteoarthritis-related differences in muscle co-activation during weight-bearing tasks.

BACKGROUND: Individuals with knee osteoarthritis (OA) demonstrate impairments in muscle function (i.e. muscle weakness, high muscle co-activation believed to have detrimental effects on joint integrity). Women with knee OA exhibit poorer health outcomes than men. Sex and muscle function are known risk factors for knee OA. It is unclear how these risk factors are associated with muscle function in knee OA and the implications for disease aetiology. RESEARCH QUESTION: How does sex and knee osteoarthritis disease status relate to muscle function, specifically strength and muscle co-activation, during walking, stair negotiation and sit-to-walk activities. METHODS: A cross-sectional study assessed muscle co-activation in 77 individuals with knee OA (mean[SD], 62.5[8.1] years; 48/29 women/men) and 18 age-matched controls (62.5[10.4] years; 9/9 women/men), during a series of walking, stair ascent and descent and sit-to-walk activities. Muscle strength of the knee extensors and flexors was assessed using maximal voluntary isometric contractions (MVIC). Electromyography was recorded from the vastus lateralis/medalis, rectus femoris, biceps femoris, semitendinosus, medial/lateral gastrocnemius normalised to MVIC. Multiple regression assessed the relationship between sex, disease status, and muscle strength on muscle co-activation. RESULTS: Individuals with knee OA were weaker than controls, had higher hamstrings-quadriceps and medial-lateral co-activation for specific phases of gait. Women were weaker than men with higher muscle co-activation across all activities. Sex and muscle weakness, but not age or disease status predicted high muscle co-activation. SIGNIFICANCE: High muscle co-activation was associated with female sex and muscle weakness regardless of disease status and age. High muscle co-activation is believed to be a compensatory mechanism for muscle weakness to maintain a certain level of function. High muscle co-activation is also thought to have detrimental effects on cartilage and joint integrity this may explain high muscle co-activation in women with muscle weakness and contribute to increased risk of incidence and progression of knee OA in women.