David J. Hunter’s research while affiliated with Southern Medical University and other places

Introduction We compared the 12-months effects of arthroscopic surgery and physiotherapist-led care for femoroacetabular impingement (FAI) syndrome on the time-varying magnitude of hip contact force and muscle contributions to hip contact force during walking. Methods Secondary analysis was performed on thirty-seven individuals with FAI syndrome who received biomechanical assessment before and 12-months following either arthroscopic surgery (n = 17) or physiotherapist-led care (Personalised Hip Therapy, PHT) (n = 20). At both time points, three-dimensional whole-body motions, ground reaction forces, and surface electromyograms (n = 14) were acquired during overground walking. A neuromusculoskeletal model was used to determine hip contact force and muscle contributions to hip contact force. Two-way repeated measures analyses of variance, implemented through statistical parametric mapping, were used to assess interactions between, and main effects of, treatment (arthroscopy vs. PHT) and time (baseline vs. follow-up) on time-varying magnitude of hip contact force and muscle contributions to hip contact force. Effects were reported as mean differences (normalized to bodyweight, BW) with 95% confidence intervals [95% CI, lower, upper bound]. Results For both treatment groups, hip contact force was larger at 12-months compared to their respective baseline (mean increase across stride, arthroscopy: 0.97 BW [95% CI 0.49, 1.46] p < .001; PHT: 1.05 BW [95% CI 0.68, 1.43] p < .001), however, no interaction effects were found. For both treatment groups, hip flexor, adductor, and abductor muscle groups made greater contributions to hip contact force after 12-months compared to baseline, while hip extensors made smaller contributions. Conclusions Compared to baseline, both treatments resulted in 12-months increases in hip contact force during walking caused by larger flexor, adductor, and abductor muscle forces at follow-up. At 12-months, hip contact force magnitude remained different normative values reported for healthy individuals, indicating neither treatment fully restored hip biomechanics.

Objective The Osteoarthritis Chronic Care Program (OACCP) has been implemented in Australian public hospitals to deliver best evidence osteoarthritis (OA) care. It is important to ensure that the OACCP continues to deliver evidence‐based OA care as intended. We aimed to identify barriers and enablers to delivering the OACCP, prioritize the barriers, and generate strategies to address them. Methods This study provides a worked example of a seven‐step theory‐informed codesign framework. We invited OACCP coordinators to participate in semistructured interviews (analyzed thematically) and complete a questionnaire to identify barriers and enablers to delivery of the OACCP. We then invited a broader group of stakeholders (OACCP coordinators, health managers, policy makers, consumers, and researchers) to prioritize the barriers via a short survey (survey 2). We held five codesign workshops in which we mapped the priority barriers to the Theoretical Domains Framework and developed strategies to address them. Results Sixteen coordinators were interviewed, and the main barriers identified were as follows: (1) patients often have beliefs that are inconsistent with best evidence care, (2) there are aspects of clinical care that are not delivered optimally, and (3) system‐level factors are a barrier to optimal patient care and sustainability of the OACCP. We codesigned a plan for action with patient educational materials, shared decision‐making tools, and health professional education and training. Conclusion Our worked example of codesign used a theory‐based, data‐driven approach with key stakeholders, identified and prioritized barriers to the delivery of the OACCP, acknowledged enablers, and generated a plan for feasible strategies to improve the program.

Objective The study objective was to determine whether the clinical response of older adults with knee osteoarthritis and overweight or obesity to 18 months of diet and exercise (D + E) or attention control (C) interventions differed between participants from rural versus urban communities. Methods Participants were 823 older adults (mean age, 64.6 years; 77% women) with knee osteoarthritis and overweight or obesity who resided in rural (n = 410) and urban (n = 413) counties in North Carolina. All were enrolled in the Weight Loss and Exercise for Communities with Arthritis in North Carolina clinical trial that randomly assigned participants to either 18 months of D + E or C interventions. General linear models were used to examine differences in clinical outcomes between rural and urban groups after adjusting for covariates. Results The rural group had significant differences (P < 0.05) at baseline in clinical outcomes, education, comorbidities, medication use, and income compared with the urban dwellers. After adjusting for baseline differences, the group (rural or urban) by treatment (D + E or C) interactions for Western Ontario McMasters Universities Osteoarthritis Index (WOMAC) pain (rural: D + E – C = −0.63, 95% confidence interval [CI] −1.31 to 0.06; urban: D + E − C= −0.29, 95% CI −0.99 to 0.41; P = 0.50) and WOMAC function (rural: D + E − C = −4.60, 95% CI −6.89 to −2.31; urban: D + E − C = −1.38, 95% CI −3.73 to 0.94; P = 0.054) indicated that the groups responded similarly to the interventions. Conclusion Among participants with knee osteoarthritis and overweight or obesity, D + E compared to C led to similar pain outcomes in rural and urban dwellers that favored D + E. The possibility that there may be greater differential efficacy in functional outcomes among rural participants needs further study. image

Objective To assess whether change of semiquantitatively magnetic resonance imaging (MRI)-defined bone marrow lesions (BMLs) and inflammatory markers is associated with change in quantitatively-assessed cartilage loss in the femorotibial joint (FTJ) in knees with radiographic osteoarthritis (OA) over 24 months. Design Participants were included from the IMI-APPROACH and the Osteoarthritis Initiative FNIH studies. Semiquantitative MRI assessment was performed for BMLs, Hoffa- and effusion-synovitis. Quantitative cartilage thickness measurements were performed manually. Definitions of change included number of subregions with BMLs, change in sum and change in maximum increase in size. Change in Hoffa-synovitis and effusion-synovitis was categorized in addition. Between-group comparisons regarding cartilage loss in the FTJ, medial and lateral compartments were performed using analysis of variance (ANOVA). Results A total of 629 participants were included. Knees without any BMLs at baseline (BL) and follow-up (FU) had significantly less cartilage loss compared to the other subgroups. Change in both directions in the sum score of BMLs was associated with increased rates of cartilage loss. Maximum increase in size of BMLs was associated with increased rates of cartilage loss (FTJ increase by 2 grades −0.183 mm, 95% CI [−0.335, −0.031], by 3 grades −0.306 mm, [−0.511, −0.101]). Worsening of Hoffa-synovitis was associated with increased rates of cartilage loss. Conclusion Knees without BMLs at BL and FU showed lowest rates of cartilage loss. Knees with an increase in BML size showed increased rates of concurrent cartilage loss. Approaches with the aim to inhibit BML development, avoidance of increase in size and avoidance of Hoffa-synovitis worsening may have beneficial effects on cartilage loss.

Objective This study aims to evaluate the time point and magnitude of peak effectiveness of exercise and the effects of various exercise modalities for osteoarthritis (OA) symptoms and to identify factors that significantly affect the effectiveness of exercise. Design Pharmacodynamic model-based meta-analysis (MBMA). Data sources Embase, PubMed, Cochrane Library, Web of Science and Scopus were searched for randomised controlled trials (RCTs) examining the effect of exercise for OA from inception to 20 November 2023. Eligibility criteria RCTs of exercise interventions in patients with knee, hip or hand OA, using Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) subscales or Visual Analogue Scale (VAS) pain scores as outcome measures, were included. The minimum clinically important difference (MCID) for WOMAC total, pain, stiffness, function and VAS pain was 9.0, 1.6, 0.8, 5.4 and 0.9, respectively. Results A total of 186 studies comprising 12 735 participants with symptomatic or radiographic knee, hip or hand OA were included. The effectiveness of exercise treatments peaked at 1.6–7.2 weeks after initiation of exercise interventions. Exercise was more effective than the control, but the differences in the effects of exercise compared with control on all outcomes were only marginally different with the MCID (7.5, 1.7, 1.0, 5.4 and 1.2 units for WOMAC total, pain, stiffness, function and VAS pain, respectively). During a 12-month treatment period, local exercise (strengthening muscles and improving mobilisations of certain joints) had the best effectiveness (WOMAC pain decreasing by 42.5% at 12 weeks compared with baseline), followed by whole-body plus local exercise. Adding local water-based exercise (eg, muscle strengthening in warm water) to muscle strengthening exercise and flexibility training resulted in 7.9, 0.5, 0.7 and 8.2 greater improvements in the WOMAC total score, pain, stiffness and function, respectively. The MBMA models revealed that treatment responses were better in participants with more severe baseline symptom scores for all scales, younger participants for the WOMAC total and pain scales, and participants with obesity for the WOMAC function. Subgroup analyses revealed participants with certain characteristics, such as female sex, younger age, knee OA or more severe baseline symptoms on the WOMAC pain scale, benefited more from exercise treatment. Conclusion Exercise reaches peak effectiveness within 8 weeks and local exercise has the best effectiveness, especially if local water-based exercise is involved. Patients of female sex, younger age, obesity, knee OA or more severe baseline symptoms appear to benefit more from exercise treatment than their counterparts.

Background Bone marrow lesions (BMLs) are a known risk factor for incident knee osteoarthritis (OA), and deep learning (DL) methods can assist in automated segmentation and risk prediction. Purpose To develop and validate a DL model for quantifying tibiofemoral BML volume on MRI scans in knees without radiographic OA and to assess the association between longitudinal BML changes and incident knee OA. Materials and Methods This retrospective study included knee MRI scans from the Osteoarthritis Initiative prospective cohort (February 2004-October 2015). The DL model, developed between August and October 2023, segmented the tibiofemoral joint into 10 subregions and measured BML volume in each subregion. Baseline and 4-year follow-up MRI scans were analyzed. Knees without OA at baseline were categorized into three groups based on 4-year BML volume changes: BML-free, BML regression, and BML progression. The risk of developing radiographic and symptomatic OA over 9 years was compared among these groups. Results Included were 3869 non-OA knees in 2430 participants (mean age, 59.5 years ± 9.0 [SD]; female-to-male ratio, 1.3:1). At 4-year follow-up, 2216 knees remained BML-free, 1106 showed an increase in BML volume, and 547 showed a decrease in BML volume. BML progression was associated with a higher risk of developing radiographic knee OA compared with remaining BML-free (hazard ratio [HR] = 3.0; P < .001) or BML regression (HR = 2.0; P < .001). Knees with BML progression also had a higher risk of developing symptomatic OA compared with BML-free knees (HR = 1.3; P < .001). Larger volume changes in BML progression were associated with a higher risk of developing both radiographic OA (HR = 2.0; P < .001) and symptomatic OA (HR = 1.7; P < .001). In almost all subchondral plates, especially the medial femur and tibia, BML progression was associated with a higher risk of developing both radiographic and symptomatic OA compared with remaining BML-free. Conclusion Knees with BML progression, according to subregion and extent of volume changes, were associated with an increased risk of OA compared with BML-free knees and knees with BML regression, highlighting the potential utility of monitoring BML volume changes in evaluating interventions to prevent OA development. ClinicalTrials.gov Identifier: NCT00080171 © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Said and Sakly in this issue.