Global, regional, and national burden of osteoarthritis, 1990-2020 and projections to 2050: a systematic analysis for the Global Burden of Disease Study 2021

The social and organisational factors shaping acceptability of a self-management education and exercise intervention for people with hip or knee osteoarthritis in Greenland

This study aimed to explore the experiences and perspectives of people with osteoarthritis attending the "Osteoarthritis School" (OA School) in Nuuk, Greenland to generate insights and lessons that can inform the development of self-management education and exercise interventions for people with other lifestyle conditions in a Greenland context. We conducted a qualitative interpretive description (ID) study based on ten semi-structured interviews with people with hip or knee osteoarthritis. Interviews were audio-recorded, transcribed, and coded. Using ID, we identified three themes: 1) perceptions and experiences of how the OA School intervention was organised (time and place); 2) perspectives and experiences of the education and exercise components (social factors, motivation, and education); and 3) significant change stories (physical and mental improvements and increased knowledge of OA). Social and organisational factors, such as working out with peers and the time and place of the intervention, influenced the participants' acceptance of the OA School intervention. Knowledge from this study will help us gain insight into what to address when developing future self-management education and exercise interventions in the Greenlandic healthcare system.

Barriers and facilitators to implementation of an exercise and education programme for osteoarthritis: a qualitative study using the consolidated framework for implementation research

Targeted efforts to better understand the barriers and facilitators of stakeholders and healthcare settings to implementation of exercise and education self-management programmes for osteoarthritis (OA) are needed. This study aimed to explore the barriers and facilitators to the implementation of Good Life with osteoArthritis in Denmark (GLA:D), a supervised group guideline-based OA programme, across Irish public and private healthcare settings. Interviews with 10 physiotherapists (PTs; 8 public) and 9 people with hip and knee OA (PwOA; 4 public) were coded by the Consolidated Framework for Implementation Research (CFIR) constructs in a case memo (summary, rationale, quotes). The strong positive/negative implementation determinants were identified collaboratively by rating the valence and strength of CFIR constructs on implementation. Across public and private settings, PTs and PwOA strongly perceived GLA:D Ireland as evidence-based, with easily accessible education and modifiable marketing/training materials that meet participants' needs, improve skills/confidence and address exercise beliefs/expectations. Despite difficulties in scheduling sessions (e.g., work/caring responsibilities), PTs in public and private settings perceived advantages to implementation over current clinical practice (e.g., shortens waiting lists). Only PTs in public settings reported limited availability of internal/external funding, inappropriate space, marketing/training tools, and inadequate staffing. Across public and private settings, PwOA reported adaptability, appropriate space/equipment and coaching/supervision, autonomy, and social support as facilitators. Flexible training and tailored education for stakeholders and healthcare settings on guideline-based OA management may promote implementation. Additional support on organising (e.g., scheduling clinical time), planning (e.g., securing appropriate space, marketing/training tools), and funding (e.g., accessing dedicated internal/external grants) may strengthen implementation across public settings.

Osteoarthritis as an Enhanceropathy: Gene Regulation in Complex Musculoskeletal Disease

PURPOSE OF REVIEW

Osteoarthritis is a complex and highly polygenic disease. Over 100 reported osteoarthritis risk variants fall in non-coding regions of the genome, ostensibly conferring functional effects through the disruption of regulatory elements impacting target gene expression. In this review, we summarise the progress that has advanced our knowledge of gene enhancers both within the field of osteoarthritis and more broadly in complex diseases.

RECENT FINDINGS

Advances in technologies such as ATAC-seq have facilitated our understanding of chromatin states in specific cell types, bolstering the interpretation of GWAS and the identification of effector genes. Their application to osteoarthritis research has revealed enhancers as the principal regulatory element driving disease-associated changes in gene expression. However, tissue-specific effects in gene regulatory mechanisms can contribute added complexity to biological interpretation. Understanding gene enhancers and their altered activity in specific cell and tissue types is the key to unlocking the genetic complexity of osteoarthritis. The use of single-cell technologies in osteoarthritis research is still in its infancy. However, such tools offer great promise in improving our functional interpretation of osteoarthritis GWAS and the identification of druggable targets. Large-scale collaborative efforts will be imperative to understand tissue and cell-type specific molecular mechanisms underlying enhancer function in disease.

Toward designing human intervention studies to prevent osteoarthritis after knee injury: A report from an interdisciplinary OARSI 2023 workshop

Objective

The global impact of osteoarthritis is growing. Currently no disease modifying osteoarthritis drugs/therapies exist, increasing the need for preventative strategies. Knee injuries have a high prevalence, distinct onset, and strong independent association with post-traumatic osteoarthritis (PTOA). Numerous groups are embarking upon research that will culminate in clinical trials to assess the effect of interventions to prevent knee PTOA despite challenges and lack of consensus about trial design in this population. Our objectives were to improve awareness of knee PTOA prevention trial design and discuss state-of-the art methods to address the unique opportunities and challenges of these studies.

Design

An international interdisciplinary group developed a workshop, hosted at the 2023 Osteoarthritis Research Society International Congress. Here we summarize the workshop content and outputs, with the goal of moving the field of PTOA prevention trial design forward.

Results

Workshop highlights included discussions about target population (considering risk, homogeneity, and possibility of modifying osteoarthritis outcome); target treatment (considering delivery, timing, feasibility and effectiveness); comparators (usual care, placebo), and primary symptomatic outcomes considering surrogates and the importance of knee function and symptoms other than pain to this population.

Conclusions

Opportunities to test multimodal PTOA prevention interventions across preclinical models and clinical trials exist. As improving symptomatic outcomes aligns with patient and regulator priorities, co-primary symptomatic (single or aggregate/multidimensional outcome considering function and symptoms beyond pain) and structural/physiological outcomes may be appropriate for these trials. To ensure PTOA prevention trials are relevant and acceptable to all stakeholders, future research should address critical knowledge gaps and challenges.

The common marmoset as a translational model of age-related osteoarthritis

Age-related osteoarthritis (OA) is a degenerative joint disease characterized by pathological changes in nearly every intra- and peri-articular tissue that contributes to disability in older adults. Studying the etiology of age-related OA in humans is difficult due to an unpredictable onset and insidious nature. A barrier in developing OA modifying therapies is the lack of translational models that replicate human joint anatomy and age-related OA progression. The purpose of this study was to determine whether the common marmoset is a faithful model of human age-related knee OA. Semi-quantitative microCT scoring revealed greater radiographic OA in geriatric versus adult marmosets, and the age-related increase in OA prevalence was similar between marmosets and humans. Quantitative assessments indicate greater medial tibial cortical and trabecular bone thickness and heterogeneity in geriatric versus adult marmosets which is consistent with an age-related increase in focal subchondral bone sclerosis. Additionally, marmosets displayed an age-associated increase in synovitis and calcification of the meniscus and patella. Histological OA pathology in the medial tibial plateau was greater in geriatric versus adult marmosets driven by articular cartilage damage, proteoglycan loss, and altered chondrocyte cellularity. The age-associated increase in medial tibial cartilage OA pathology and meniscal calcification was greater in female versus male geriatric marmosets. Overall, marmosets largely replicate human OA as evident by similar 1) cartilage and skeletal morphology, 2) age-related progression in OA pathology, and 3) sex differences in OA pathology with increasing age. Collectively, these data suggest that the common marmoset is a highly translatable model of the naturally occurring, age-related OA seen in humans.

Long-Term Efficacy Following Intra-articular Injection of Carboxymethyl-chitosan, a New Product Class for Knee Osteoarthritis: Results from an Observational Study in Germany

INTRODUCTION

Evaluate the real-world efficacy of a single intra-articular injection of carboxymethyl-chitosan (CM-chitosan), a new product class for knee osteoarthritis (OA).

METHODS

This post-marketing study included adult patients with knee OA, who received a single injection of 60 mg CM-chitosan (currently marketed as KioMedinevsone) according to the instructions for use. Follow-up was performed at weeks 1, 12, 24, and 36. Efficacy was evaluated using a Visual Analog Scale (VAS) score for pain, the Knee injury and Osteoarthritis Outcome Score (KOOS), Patient's Global Assessment (PGA), and overall patient satisfaction.

RESULTS

Forty-nine patients were included in the study. VAS pain score significantly decreased from a median of 49.0 mm at baseline to 24.0 mm at week 1 and to 18 mm at week 36. Pain improvement was stable since at week 36; 91.8% of patients confirmed pain reduction. All KOOS subscales (symptoms, pain, activities of daily living, sports and recreational activities, quality of life) improved significantly compared to baseline at all time points. KOOS pain improved progressively from a median of 58.3% at baseline (mean 56.2 ± 18.8%) to 86.1% (mean 74.1 ± 24%) at week 36 compared to baseline. Overall, more than 70% of patients reported a condition gain (PGA), matching well with the more than 75% of patients being satisfied with the treatment. At 6 months, 72.7% of the patients could be classified as responder according to the OMERACT-OARSI proposed set of responder criteria.

CONCLUSION

CM-chitosan showed a rapid onset of pain relief after 1 week and with a duration of 9 months. In a real-world setting, treatment with CM-chitosan would appear to be a potentially effective option to reduce pain and improve physical function and global condition in patients with knee OA, opening new perspectives in patients who are considered as refractory to current symptomatic therapies and where the unmet need is high.

TRIAL REGISTRATION NUMBER

NCT04757051 (ClinicalTrials.gov).

Understanding tightened muscle in knee osteoarthritis and the impacts of Fu's subcutaneous needling: A pilot trial with shear-wave elastography and near-infrared spectroscopy

BACKGROUND

Given the scarce reports on the interplay between Fu's subcutaneous needling (FSN), tightened muscle, and therapeutic effects, we developed a clinical research protocol to synchronously collect data on clinical efficacy and muscle characteristics in patients with knee osteoarthritis, exploring the mechanism of FSN action. The primary aim was to assess the feasibility and safety of this protocol, guiding future trials and their sample size calculations.

METHODS

In this prospective, single-blind, self-controlled study, 19 patients with early to mid-stage unilateral knee osteoarthritis underwent FSN therapy on both knees over 1 week (4 sessions, every other day). We measured local elastic modulus, muscle thickness, blood flow volume, and oxygen consumption rate of bilateral vastus lateralis muscles using shear-wave elastography and near-infrared spectroscopy (NIRS) before and after the first and fourth treatments. Additionally, real-time NIRS indicators (oxygenated hemoglobin [O2Hb], deoxyhemoglobin [HHb], total hemoglobin [THb], and tissue saturation index [TSI]) were recorded during these treatments. Pain intensity (visual analogue scale [VAS]), functional status (Western Ontario and McMaster Universities Osteoarthritis Index [WOMAC]), and active range of motion were evaluated before these treatments.

RESULTS

All 19 participants completed the trial without serious adverse events. After 3 FSN treatments, significant changes were observed in VAS and WOMAC scores (VAS: P < .001; WOMAC: P < .001), and knee flexion (P < .001) and external rotation (P = .02), except for internal rotation. No meaningful significant differences were observed in muscle characteristics at baseline or between pre- and post-treatment periods. NIRS results during treatments indicated significant increases in local O2Hb and THb post-FSN therapy (First treatment: O2Hb: P = .005; THb: P = .006. Fourth treatment: O2Hb: P = .002; THb: P = .004); however, no significant increases were observed for HHb (First treatment: P = .06; Fourth treatment: P = .28). No linear correlation was found between therapeutic effects and changes in tightened muscle indices.

CONCLUSION

FSN reduces pain and improves joint function in knee osteoarthritis, while also enhancing blood flow and oxygenation in the vastus lateralis muscle of the affected side. Further revisions of this protocol are warranted based on our insights.

Correlation of growth differentiation factor-5 + 104T>C polymorphism with the risk of knee, hand, and hip osteoarthritis: a case-control study and meta-analysis based on 47 case-control studies

Osteoarthritis (OA) arises from a intricate interplay of genetic and environmental factors. Numerous studies have explored the link between the growth differentiation factor 5 (GDF-5) +104T>C polymorphism and OA risk, but the findings have been inconclusive. We carried out a case-control study with 704 OA cases and 418 healthy controls. Furthermore, we conducted a meta-analysis by thoroughly searching the literature for relevant studies published until 1 September, 2023. The combined odds ratio and 95% confidence intervals were used to assess the correlation's strength. A total of 47 independent case-control studies, including 17,602 OA cases and 30,947 controls, were analyzed. Of these, 31 studies (11,176 cases, 16,724 controls) focused on knee OA, 8 studies (3,973 cases, 8,055 controls) examined hip OA, and 6 studies (2244 cases, 5965 controls) investigated hand OA. Overall, our findings suggest that the GDF-5 + 104T>C polymorphism has a protectibe role in development of OA in global scale. Subgroup analyses by ethnicity indicated that this genetic variation provides protection against OA in Caucasian, Asian, and African populations. Further subgroup analysis based on the type of OA showed a decreased risk of knee and hand OA associated with this variation, but not for hip OA. Our combined data indicates that the GDF-5 + 104T>C polymorphism offers protection against the development of OA in general, as well as knee and hand OA. Nevertheless, there was no correlation found between this polymorphism and the development of hip OA.

Association between hyperuricemia and the risk of mortality in patients with osteoarthritis: A study based on the National Health and Nutrition Examination Survey database

BACKGROUND

The purpose of this study was to evaluate the relationship between hyperuricemia and the risks of all-cause mortality and cardiovascular disease (CVD) mortality in patients with osteoarthritis (OA).

METHODS

A retrospective cohort study was performed on 3,971 patients using data from the National Health and Nutrition Examination Survey database between 1999 and 2018. OA was diagnosed through specific questions and responses. The weighted COX regression models were used to explore the factors associated with all-cause mortality/CVD mortality in OA patients. Subgroup analyses were conducted based on age, gender, hypertension, dyslipidemia, CVD, and chronic kidney disease (CKD). Hazard ratio (HR) and 95% confidence interval (95% CI) were measured as the evaluation indexes.

RESULTS

During the duration of follow-up time (116.38 ± 2.19 months), 33.69% (1,338 patients) experienced all-cause mortality, and 11.36% (451 patients) died from CVD. Hyperuricemia was associated with higher risks of all-cause mortality (HR: 1.22, 95% CI: 1.06-1.41, P = 0.008) and CVD mortality (HR: 1.32, 95% CI: 1.02-1.72, P = 0.036) in OA patients. Subgroup analyses showed that hyperuricemia was related to the risk of all-cause mortality in OA patients aged >65 years (HR: 1.17, 95% CI: 1.01-1.36, P = 0.042), in all male patients (HR: 1.41, 95% CI: 1.10-1.80, P = 0.006), those diagnosed with hypertension (HR: 1.17, 95% CI: 1.01-1.37, P = 0.049), dyslipidemia (HR: 1.18, 95% CI: 1.01-1.39, P = 0.041), CVD (HR: 1.30, 95% CI: 1.09-1.55, P = 0.004), and CKD (HR: 1.31, 95% CI: 1.01-1.70, P = 0.046). The association between hyperuricemia and a higher risk of CVD mortality was found in OA patients aged ≤ 65 years (HR: 1.90, 95% CI: 1.06-3.41, P = 0.032), who did not suffer from diabetes (HR: 1.36, 95% CI: 1.01-1.86, P = 0.048), who did not suffer from hypertension (HR: 2.56, 95% CI: 1.12-5.86, P = 0.026), and who did not suffer from dyslipidemia (HR: 2.39, 95% CI: 1.15-4.97, P = 0.020).

CONCLUSION

These findings emphasize the importance of monitoring serum uric acid levels in OA patients for potentially reducing mortality associated with the disease.

Collaborative model of care between orthopaedics and allied healthcare professionals (CONNACT) in knee osteoarthritis: Effectiveness-implementation hybrid randomized controlled trial of a community-based, multidisciplinary, stratified intervention

OBJECTIVE

To compare the clinical and cost effectiveness of the Collaborative Model of Care between Orthopaedics and Allied Healthcare Professionals (CONNACT), a community-based, stratified, multidisciplinary intervention consisting of exercise, education, psychological and nutrition delivered through a chronic care model to usual hospital care in adults with knee osteoarthritis (OA).

METHODS

Pragmatic, parallel-arm, single-blinded superiority RCT trial. Community-dwelling, ambulant adults with knee OA (Kellgren-Lawrence grade > 1; Knee Injury and OA Outcome Score (KOOS4) ≤75) were enrolled. Primary outcome was KOOS4 at 12-months; secondary outcomes included: quality of life, physical performance measures, symptom satisfaction, psychological outcomes, dietary habits, and global perceived effect. Intention-to-treat analysis using generalized linear model (GLM) and regression modeling were conducted. Economic evaluation through a societal approach was embedded.

RESULTS

110 participants (55 control, 55 intervention) were randomized. No between-group difference found for the primary outcome (MD [95%CI]: -1.86 [-9.11. 5.38]), although both groups demonstrated within-group improvement over 12-months. Among the secondary outcomes, the CONNACT group demonstrated superior dietary change (12 months) and physical performance measures (3 months), and global perceived effect (6 months). While there was no between-group difference in total cost, significant productivity gains (reduced indirect cost) were seen in the CONNACT group.

CONCLUSION

CONNACT was not superior to usual care at 1 year. Further efforts are needed to understand the underlying contextual and implementation factors in order to further improve and refine such community-based, stratified care models moving forward.

TRIAL REGISTRATION

Clinicaltrials.gov Identifier: NCT03809975. Registered January 18, 2019. https://clinicaltrials.gov/ct2/show/NCT03809975.

Economic impact of informal caring for a person with arthritis in Australia from 2015 to 2030: a microsimulation approach using national survey data

OBJECTIVES

To estimate the economic burden of informal caregivers not in the labour force (NILF) due to caring for a person with arthritis in Australia, with projections of these costs from 2015 to 2030.

DESIGN

Static microsimulation modelling using national survey data.

SETTING

Australia nationwide survey.

PARTICIPANTS

Participants include respondents to the Survey of Disability, Ageing and Carers who are informal carers of a person who has arthritis as their main chronic condition and non-carers.

OUTCOME MEASURES

Estimating the economic impact and national aggregated costs of informal carers NILF to care for a person with arthritis and projecting these costs from 2015 to 2030 in 5-year intervals.

RESULTS

On a per-person basis, when adjusted for age, sex and highest education attained, the difference in average weekly total income between informal carers and non-carers employed in the labour force is $A1051 (95% CI: $A927 to $A1204) in 2015 and projected to increase by up to 22% by 2030. When aggregated, the total national annual loss of income to informal carers NILF is estimated at $A388.2 million (95% CI: $A324.3 to $A461.9 million) in 2015, increasing to $A576.9 million (95% CI: $A489.2 to $A681.8 million) by 2030. The national annual tax revenue lost to the government of the informal carers NILF is estimated at $A99 million (95% CI: $A77.9 to $A126.4 million) in 2015 and is projected to increase 49% by 2030.

CONCLUSION

Informal carers NILF are economically worse off than employed non-carers, and the aggregated national annual costs are substantial. The future economic impact of informal carers NILF to care for a person with arthritis in Australia is projected to increase, with the estimated differences in income between informal carers and employed non-carers increasing by 22% from 2015 to 2030.

Alternative models to support weight loss in chronic musculoskeletal conditions: effectiveness of a physiotherapist-delivered intensive diet programme for knee osteoarthritis, the POWER randomised controlled trial

OBJECTIVES

To determine if physiotherapists can deliver a clinically effective very low energy diet (VLED) supplementary to exercise in people with knee osteoarthritis (OA) and overweight or obesity.

METHODS

88 participants with knee OA and body mass index (BMI) >27 kg/m2 were randomised to either intervention (n=42: VLED including two daily meal replacement products supplementary to control) or control (n=46: exercise). Both interventions were delivered by unblinded physiotherapists via six videoconference sessions over 6 months. The primary outcome was the percentage change in body weight at 6 months, measured by a blinded assessor. Secondary outcomes included BMI, waist circumference, waist-to-hip ratio, self-reported measures of pain, function, satisfaction and perceived global change, and physical performance tests.

RESULTS

The intervention group lost a mean (SD) of 8.1% (5.2) body weight compared with 1.0% (3.2) in the control group (mean (95% CI) between-group difference 7.2% (95% CI 5.1 to 9.3), p<0.001), with significantly lower BMI and waist circumference compared with control group at follow-up. 76% of participants in the intervention group achieved ≥5% body weight loss and 37% acheived ≥10%, compared with 12% and 0%, respectively, in the control group. More participants in the intervention group (27/38 (71.1%)) reported global knee improvement than in the control group (20/42 (47.6%)) (p=0.02). There were no between-group differences in any other secondary outcomes. No serious adverse events were reported.

CONCLUSION

A VLED delivered by physiotherapists achieved clinically relevant weight loss and was safe for people with knee OA who were overweight or obese. The results have potential implications for future service models of care for OA and obesity.

TRIAL REGISTRATION NUMBER

NIH, US National Library of Medicine, Clinicaltrials.gov NCT04733053 (1 February 2021).

Cyaonoside A-loaded composite hydrogel microspheres to treat osteoarthritis by relieving chondrocyte inflammation

Cyaonoside A (CyA), derived from the natural Chinese medicine, Cyathula officinalis Kuan, which was for a long time used to treat knee injuries and relieve joint pain in traditional Chinese medicine, showed an unclear mechanism for protecting cartilage. In addition, CyA was poorly hydrosoluble and incapable of being injected directly into the joint cavity, which limited its clinical application. This study reveals that CyA resisted IL-1β-mediated chondrogenic inflammation and apoptosis. Next, transcriptome sequencing is used to explore the potential mechanisms underlying CyA regulation of MSC chondrogenic differentiation. Based on these findings, CyA-loaded composite hydrogel microspheres (HLC) were developed and they possessed satisfactory loading efficiency, a suitable degradation rate and good biocompatibility. HLC increased chondrogenic anabolic gene (Acan, COL2A, and SOX9) expression, while downregulating the expression of the catabolic marker MMP13 in vitro. In the osteoarthritis mouse model, HLC demonstrated promising therapeutic capabilities by protecting the integrity of articular cartilage. In conclusion, this study provides insights into the regulatory mechanisms of CyA for chondrocytes and proposes a composite hydrogel microsphere-based advanced therapeutic strategy for osteoarthritis.

Equine-assisted service's effect on cartilage and skeletal biomarkers for adults and older adults with arthritis: A pilot study

OBJECTIVE

The object of this study was to determine the effect of EAS (Equine-Assisted Services) on arthritis conditions, as measured by the sTnT (Skeletal troponin) and COMP (cartilage oligomeric matrix proteins) biomarkers, compared to an exercise attention control intervention.

DESIGN

This was a secondary analysis of a randomized clinical trial comparing equine-assisted therapy to exercise education attention-control on cartilage and skeletal biomarkers in adults with arthritis. Twenty-one adults (Mage = 64 years) with arthritis who attended rheumatology clinics in the midwestern United States participated.

RESULTS

No changes were found in sTnT from baseline to week six within either intervention nor were there differences in changes between the two groups (p = 0.91). COMP increased from baseline to week six for both conditions, suggesting increased deterioration of cartilage and joints. Although the attention-control condition demonstrated larger increases in cartilage oligomeric matrix proteins level, compared to the EAS condition, these differences were not statistically (p = 0.58) or clinically significant (i.e., trivial effect, d = -0.16). When 3 outliers were removed, the differences in changes between EAT and attention-control group could be arguably of clinical significance (d = - 0.33), suggesting that the attention-control group demonstrated larger increases in levels of COMP than those in the EAS condition, though this difference was not statistically significant (p = 0.28).

CONCLUSION

Although equine-assisted therapy may reduce pain and improve quality of life for adults with arthritis, findings here are not fully corroborated with biomarkers.

Total Knee Arthroplasty Versus Education and Exercise for Knee Osteoarthritis: A Propensity-Matched Analysis

OBJECTIVE

We estimate the treatment effect of total knee arthroplasty (TKA) versus an education and exercise (Edu+Ex) program on pain, function, and quality of life outcomes 3 and 12 months after treatment initiation for knee osteoarthritis (OA).

METHODS

Patients with knee OA who had undergone TKA were matched on a 1:1 ratio with participants in an Edu+Ex program based on a propensity score fitted to a range of pretreatment covariates. After matching, between-group differences in improvement (the treatment effect) in Knee Injury and Osteoarthritis Outcome Score 12-item version (0, worst to 100, best) pain, function, and quality of life from baseline to 3 and 12 months were estimated using linear mixed models, adjusting for unbalanced covariates, if any, after matching.

RESULTS

The matched sample consisted of 522 patients (Edu+Ex, n = 261; TKA, n = 261) who were balanced on all pretreatment characteristics. At 12-month follow-up, TKA resulted in significantly greater improvements in pain (mean difference [MD] 22.8; 95% confidence interval [95% CI] 19.7-25.8), function (MD 21.2; 95% CI 17.7-24.4), and quality of life (MD 18.3; 15.0-21.6). Even so, at least one-third of patients receiving Edu+Ex had a clinically meaningful improvement in outcomes at 12 months compared with 75% of patients with TKA.

CONCLUSION

TKA is associated with greater improvements in pain, function, and quality of life, but these findings also suggest that Edu+Ex may be a viable alternative to TKA in a meaningful proportion of patients, which may reduce overall TKA need. Confirmatory trials are needed.

Molecular portrait of chronic joint diseases: Defining endotypes toward personalized medicine

Joint diseases affect hundreds of millions of people worldwide, and their prevalence is constantly increasing. To date, despite recent advances in the development of therapeutic options for most rheumatic conditions, a significant proportion of patients still lack efficient disease management, considerably impacting their quality of life. Through the spectrum of rheumatoid arthritis (RA), psoriatic arthritis (PsA), and osteoarthritis (OA) as quintessential and common rheumatic diseases, this review first provides an overview of their epidemiological and clinical features before exploring how the better definition of clinical phenotypes has helped their clinical management. It then discusses the recent progress in understanding the diversity of endotypes underlying disease phenotypes. Finally, this review highlights the current challenges of implementing molecular endotypes towards the personalized management of RA, PsA and OA patients in the future.

How can clinicians enhance self-efficacy beliefs in osteoarthritis? An overview of systematic reviews with meta-analysis

This overview of reviews aimed to synthesize the effectiveness of non-pharmacological approaches to enhance self-efficacy in people with osteoarthritis. The CINAHL, Embase, PsycINFO, PubMed, SPORTDiscus, and the Cochrane Library databases were searched from inception to December 2023. We considered systematic reviews with meta-analysis of randomized clinical trials evaluating any non-pharmacological intervention. We used AMSTAR 2 to assess the methodological quality of reviews. The overlap between reviews was calculated. We included eight systematic reviews with meta-analysis evaluating 30 different clinical trials. Overall, mind-body exercises, psychological interventions, and self-management strategies may improve arthritis self-efficacy. Specifically, the meta-analyses showed tai chi exercises, coping skills training, and the arthritis self-management program are more effective than controls to enhance arthritis self-efficacy in people with hip and/or knee osteoarthritis. In addition, inconsistent results were detected across meta-analyses regarding the effectiveness of multidisciplinary interventions. Finally, the degree of overlap between all reviews was moderate (CCA = 6%) and many included reviews reported most of the items of AMSTAR 2. Tai chi exercises, coping skills training, and the arthritis self-management program may be beneficial for enhancing arthritis self-efficacy. Open Science Framework Registration: https://doi.org/10.17605/OSF.IO/VX2T6 .

Exercise and Pain Neuroscience Education for Patients With Chronic Pain After Total Knee Arthroplasty: A Randomized Clinical Trial

Importance

Up to 20% of patients develop chronic pain after total knee arthroplasty (TKA), yet there is a scarcity of effective interventions for this population.

Objective

To evaluate whether neuromuscular exercise and pain neuroscience education were superior to pain neuroscience education alone for patients with chronic pain after TKA.

Design, Setting, and Participants

A superiority randomized clinical trial was conducted at 3 outpatient clinics at Aalborg University Hospital in Denmark. Participants with moderate-to-severe average daily pain intensity and no signs of prosthesis failure at least 1 year after primary TKA were included. Participant recruitment was initiated on April 12, 2019, and completed on October 31, 2022. The 12-month follow-up was completed on March 21, 2023.

Interventions

The study included 24 sessions of supervised neuromuscular exercise (2 sessions per week for 12 weeks) and 2 total sessions of pain neuroscience education (6 weeks between each session) or the same pain neuroscience education sessions alone. The interventions were delivered in groups of 2 to 4 participants.

Main Outcomes and Measures

The primary outcome was change from baseline to 12 months using the mean score of the Knee Injury and Osteoarthritis Outcome Score, covering the 4 subscales pain, symptoms, activity of daily living, and knee-related quality of life (KOOS4; scores range from 0 to 100, with higher scores indicating better outcomes). The outcome assessors and statistician were blinded. All randomized participants were included in the intention-to-treat analysis.

Results

Among the 69 participants (median age, 67.2 years [IQR, 61.2-71.9 years]; 40 female [58%]) included in the study, 36 were randomly assigned to the neuromuscular exercise and pain neuroscience education group, and 33 to the pain neuroscience education-alone group. The intention-to-treat analysis showed no between-group difference in change from baseline to 12 months for the KOOS4 (7.46 [95% CI, 3.04-11.89] vs 8.65 [95% CI, 4.67-12.63] points; mean difference, -1.33 [95% CI, -7.59 to 4.92]; P = .68). Among the 46 participants who participated in the 12-month assessment in the 2 groups, 16 (34.8%) experienced a clinically important improvement (a difference of ≥10 points on the KOOS4) with no between-group difference. No serious adverse events were observed.

Conclusions and Relevance

In this randomized clinical trial, the results demonstrated that neuromuscular exercises and pain neuroscience education were not superior to pain neuroscience education alone in participants with chronic pain after TKA. Approximately one-third of the participants, regardless of intervention, experienced clinically important improvements. Future studies should investigate which patient characteristics indicate a favorable response to exercises and/or pain neuroscience education.

Trial Registration

ClinicalTrials.gov Identifier: NCT03886259.

Total Hip Arthroplasty Versus Education and Exercise: A Propensity-Matched Analysis of 266 Patients Who Have Hip Osteoarthritis

BACKGROUND

Total hip arthroplasty (THA) for osteoarthritis (OA) is a major health system cost. Education and exercise (Edu + Ex) programs may reduce the number of THAs needed, but supporting data are limited. This study aimed to estimate the treatment effect of THA versus Edu + Ex on pain, function, and quality of life outcomes 3 and 12 months after treatment initiation for hip OA.

METHODS

Patients who had hip OA who underwent THA or an Edu + Ex program were included in this propensity-matched study. In 778 patients (Edu + Ex, n = 303; THA, n = 475), propensity scores were based on pretreatment characteristics, and patients were matched on a 1:1 ratio. Between-group treatment effects (pain, function, and quality of life) were estimated as the mean difference (MD) in change from pretreatment to 3-month and 12-month follow-up using linear mixed models.

RESULTS

The matched sample consisted of 266 patients (Edu + Ex, n = 133; THA, n = 133) who were balanced on all pretreatment characteristics except opioid use. At 12-month follow-up, THA resulted in significantly greater improvements in pain (MD 35.4; 95% confidence interval [CI] 31.4 to 39.4), function (MD 30.5; 95% CI 26.3 to 34.7), and quality of life (MD 33.6; 95% CI 28.8 to 38.4). Between 17% and 30% of patients receiving Edu + Ex experienced a surgical threshold for clinically meaningful improvement in outcomes, compared to 84% and 90% of THA patients.

CONCLUSIONS

A THA provides greater improvements in pain, function, and quality of life. A notable proportion of Edu + Ex patients had clinically meaningful improvements, suggesting Edu + Ex may result in THA deferral in some patients, but confirmatory trials are needed.

Osteoarthritis: Insights into Diagnosis, Pathophysiology, Therapeutic Avenues, and the Potential of Natural Extracts

Osteoarthritis (OA) stands as a prevalent and progressively debilitating clinical condition globally, impacting joint structures and leading to their gradual deterioration through inflammatory mechanisms. While both non-modifiable and modifiable factors contribute to its onset, numerous aspects of OA pathophysiology remain elusive despite considerable research strides. Presently, diagnosis heavily relies on clinician expertise and meticulous differential diagnosis to exclude other joint-affecting conditions. Therapeutic approaches for OA predominantly focus on patient education for self-management alongside tailored exercise regimens, often complemented by various pharmacological interventions primarily targeting pain alleviation. However, pharmacological treatments typically exhibit short-term efficacy and local and/or systemic side effects, with prosthetic surgery being the ultimate resolution in severe cases. Thus, exploring the potential integration or substitution of conventional drug therapies with natural compounds and extracts emerges as a promising frontier in enhancing OA management. These alternatives offer improved safety profiles and possess the potential to target specific dysregulated pathways implicated in OA pathogenesis, thereby presenting a holistic approach to address the condition's complexities.

New therapeutic strategies in osteoarthritis

Osteoarthritis (OA) is the most prevalent arthritis-type and is a major contributor to chronic joint pain, impaired physical function, and limited mobility. By the end of 2020, a total of 595 million, equal to 7·6% of the global population, had OA; this figure is expected to rise exponentially by 2050. Even while the disorder's intricate pathophysiology is starting to appear intelligible, we are yet to have a cure for the disorder. OA is typically managed with traditional palliative measures, such as topical and systemic analgesics, including non-steroidal anti-inflammatory drugs, therapeutic exercise, and braces. Sometimes, intra-articular glucocorticoids, viscosupplementation, or regenerative interventions provide short-term pain relief and functional improvement; some may require arthroplasty. Researchers continue their efforts to unveil a new therapeutic target to be effective in OA that modifies symptoms and arrests disease progression as well. In the present literature review, insights into new therapeutic strategies in OA, for example, liposome-based dexamethasone, microspore-based triamcinolone, nerve growth factor antagonist, anti-ADAMTS-5 (A Disintegrin And Metalloproteinase Thrombospoidin Motifs - 5), pentosan polysulfate sodium, allogeneic stem cells, C-C chemokine receptor type-4 (CCR4) ligand 17 inhibitor, Wnt-signaling inhibitor, and anti-obesity medications are provided.

People with painful knee osteoarthritis hold negative implicit attitudes towards activity

ABSTRACT

Negative attitudes/beliefs surrounding osteoarthritis, pain, and activity contribute to reduced physical activity in people with knee osteoarthritis (KOA). These attitudes/beliefs are assessed using self-report questionnaires, relying on information one is consciously aware of and willing to disclose. Automatic (ie, implicit) assessment of attitudes does not rely on conscious reflection and may identify features unique from self-report. We developed an implicit association test that explored associations between images of a person moving/twisting their knee (activity) or sitting/standing (rest), and perceived threat (safe vs dangerous). We hypothesised that people with KOA would have greater implicit threat-activity associations (vs pain-free and non-knee pain controls), with implicit attitudes only weakly correlating with self-reported measures (pain knowledge, osteoarthritis/pain/activity beliefs, fear of movement). Participants (n = 558) completed an online survey: 223 had painful KOA (n = 157 female, 64.5 ± 8.9 years); 207 were pain free (n = 157 female, 49.3 ± 15.3 years); and 99 had non-KOA lower limb pain (n = 74 female, 47.5 ± 15.04 years). An implicit association between "danger" and "activity" was present in those with and without limb pain (KOA: 0.36, 95% CI 0.28-0.44; pain free: 0.13, 95% CI 0.04-0.22; non-KOA lower limb pain 0.11, 95% CI -0.03 to 0.24) but was significantly greater in the KOA group than in the pain free (P < 0.001) and non-KOA lower limb pain (P = 0.004) groups. Correlations between implicit and self-reported measures were nonsignificant or weak (rho = -0.29 to 0.19, P < 0.001 to P = 0.767). People with painful KOA hold heightened implicit threat-activity associations, capturing information unique to that from self-report questionnaires. Evaluating links between implicit threat-activity associations and real-world behaviour, including physical activity levels, is warranted.

Socioeconomic Status Affects Patient-Reported Outcome Measures in Total Hip and Knee Arthroplasty: A Retrospective Dutch Registry Study

BACKGROUND

To determine the association between socioeconomic status (SES) and patient-reported outcome measures in a Dutch cohort who have undergone total hip arthroplasty (THA) or total knee arthroplasty (TKA).

METHODS

A retrospective national registry study of all patients who underwent primary THA or TKA between 2014 and 2020 in the Netherlands was performed. Linear mixed effects regression models were used to assess the association between SES and patient-reported outcome measures for THA and TKA patients separately. The following measures were collected: numeric rating scale for pain, Oxford Hip/Knee Score, Hip/Knee disability and Osteoarthritis Outcome Score, and the EuroQol 5-Dimensions questionnaire. Sex, age, body mass index, American Society of Anesthesiologists classification, Charnley classification, and smoking status were considered as covariates in the models.

RESULTS

THA patients (n = 97,443) were on average 70 years old with a body mass index of 27.4 kg/m2, and TKA patients (n = 78,811) were on average 69 years old with a body mass index of 29.7 kg/m2. Preoperatively, patients with a lower SES undergoing THA or TKA reported more severe symptoms and lower health-related quality of life. At 1-year follow-up, they also reported lower scores and less improvement over time compared to patients with a higher SES.

CONCLUSIONS

Patients with lower SES report worse symptoms when admitted for surgery and less improvement after surgery. Future research must address potentially mediating factors of the association between SES and symptom reporting such as access to surgery and rehabilitation, subjectivity in reporting, and patient expectation for THA and TKA outcomes.

Osteoporosis, Osteoarthritis, and Subchondral Insufficiency Fracture: Recent Insights

The increased incidence of osteoarthritis (OA), particularly knee and hip OA, and osteoporosis (OP), owing to population aging, have escalated the medical expense burden. Osteoarthritis is more prevalent in older women, and the involvement of subchondral bone fragility spotlights its association with OP. Notably, subchondral insufficiency fracture (SIF) may represent a more pronounced condition of OA pathophysiology. This review summarizes the relationship between OA and OP, incorporating recent insights into SIF. Progressive SIF leads to joint collapse and secondary OA and is associated with OP. Furthermore, the thinning and fragility of subchondral bone in early-stage OA suggest that SIF may be a subtype of OA (osteoporosis-related OA, OPOA) characterized by significant subchondral bone damage. The high bone mineral density observed in OA may be overestimated due to osteophytes and sclerosis and can potentially contribute to OPOA. The incidence of OPOA is expected to increase along with population aging. Therefore, prioritizing OP screening, early interventions for patients with early-stage OA, and fracture prevention measures such as rehabilitation, fracture liaison services, nutritional management, and medication guidance are essential.

Exploring the impact of pathogenic microbiome in orthopedic diseases: machine learning and deep learning approaches

Osteoporosis, arthritis, and fractures are examples of orthopedic illnesses that not only significantly impair patients' quality of life but also complicate and raise the expense of therapy. It has been discovered in recent years that the pathophysiology of orthopedic disorders is significantly influenced by the microbiota. By employing machine learning and deep learning techniques to conduct a thorough analysis of the disease-causing microbiome, we can enhance our comprehension of the pathophysiology of many illnesses and expedite the creation of novel treatment approaches. Today's science is undergoing a revolution because to the introduction of machine learning and deep learning technologies, and the field of biomedical research is no exception. The genesis, course, and management of orthopedic disorders are significantly influenced by pathogenic microbes. Orthopedic infection diagnosis and treatment are made more difficult by the lengthy and imprecise nature of traditional microbial detection and characterization techniques. These cutting-edge analytical techniques are offering previously unheard-of insights into the intricate relationships between orthopedic health and pathogenic microbes, opening up previously unimaginable possibilities for illness diagnosis, treatment, and prevention. The goal of biomedical research has always been to improve diagnostic and treatment methods while also gaining a deeper knowledge of the processes behind the onset and development of disease. Although traditional biomedical research methodologies have demonstrated certain limits throughout time, they nevertheless rely heavily on experimental data and expertise. This is the area in which deep learning and machine learning approaches excel. The advancements in machine learning (ML) and deep learning (DL) methodologies have enabled us to examine vast quantities of data and unveil intricate connections between microorganisms and orthopedic disorders. The importance of ML and DL in detecting, categorizing, and forecasting harmful microorganisms in orthopedic infectious illnesses is reviewed in this work.

Ultrasound-guided determination demonstrates influence of age, sex and type of sport on medial femoral condyle cartilage thickness in children and adolescents

PURPOSE

To analyse the reliability of ultrasound-guided measurement of the cartilage thickness at the medial femoral condyle in athletically active children and adolescents before and after mechanical load in relation to age, sex and type of sport.

METHODS

Three successive measurements were performed in 157 participants (median/min-max age: 13.1/6.0-18.0 years, 106 males) before and after mechanical load by squats at the same site of the medial femoral condyle by defined transducer positioning. Test-retest reliability was examined using Cronbach'sα $\alpha $ calculation. Differences in cartilage thickness were analysed with respect to age, sex and type of practiced sports, respectively.

RESULTS

Excellent reliability was achieved both before and after mechanical load by 30 squats with a median cartilage thickness of 1.9 mm (range: 0.5-4.8 mm) before and 1.9 mm (0.4-4.6 mm) after mechanical load. Male cartilages were thicker (p < 0.01) before (median: 2.0 mm) and after (2.0 mm) load when compared to female cartilage (before: 1.6 mm; after: 1.7 mm). Median cartilage thickness was about three times higher in karate athletes (before: 2.3 mm; after: 2.4 mm) than in sports shooters (0.7; 0.7 mm). Cartilage thickness in track and field athletes, handball players and soccer players were found to lay in-between. Sport type related thickness changes after mechanical load were not significant.

CONCLUSION

Medial femoral condyle cartilage thickness in childhood correlates with age, sex and practiced type of sports. Ultrasound is a reliable and simple, pain-free approach to evaluate the cartilage thickness in children and adolescents.

LEVEL OF EVIDENCE

Level III.

Assessing domain match and feasibility of candidate instruments matching with OMERACT endorsed domains to measure flare in knee and hip osteoarthritis

PURPOSE

To evaluate the domain match (truth) and feasibility of candidate instruments assessing flare in knee and hip osteoarthritis (OA) according to the identified domains.

MATERIAL AND METHODS

From a literature review (575 papers), instruments were selected and evaluated using the truth and feasibility elements of the OMERACT Filter 2.2. These were evaluated by 26 experts, including patients, in two Delphi survey rounds. The final selection was obtained by a vote.

RESULTS

44 instruments were identified. In Delphi Round 1, five instruments were selected. In Round 2, all instruments obtained at least 75 % in terms of content match with the endorsed domains and feasibility. In the final selection, the Flare-OA questionnaire obtained 100 % favorable votes.

CONCLUSION

Through consensus of the working group, the Flare-OA questionnaire was selected as the best candidate instrument to move into a full assessment of its measurement properties using the OMERACT Filter 2.2.

Interference with SPARC inhibits Benzophenone-3 induced ferroptosis in osteoarthritis: Evidence from bioinformatics analyses and biological experimentation

The aim of this study is to conduct a thorough evaluation of the association between Benzophenone-3 (BP-3) exposure and OA, offering critical insights into the underlying mechanisms involved. The National Health and Nutrition Examination Survey (NHANES) database was utilized to investigate the correlation between BP-3 and osteoarthritis. Proteomic sequencing from clinical sample and the PharmMapper online tool were employed to predict the biological target of BP-3. Cellular molecular assays and transfection studies were performed to verify the prediction from bioinformatics analyses. Through cross-sectional analysis of the NHANES database, we identified BP-3 as a risk factor for OA development. The results of proteomic sequencing showed that Secreted Protein Acidic and Rich in Cysteine (SPARC) was significantly elevated in the area of damage compared to the undamaged area. SPARC was also among the potential biological targets of BP-3 predicted by the online program. Through in vitro cell experiments, we further determined that the toxicological effects of BP-3 may be due to SPARC, which elevates intracellular GPX4 levels, activates the glutathione system, and promotes lipid peroxidation to mitigate ferroptosis. Inhibiting SPARC expression has been shown to reduce inflammation and ferroptosis in OA contexts. This research provides an expansive understanding of BP-3's influence on osteoarthritis development. We have identified SPARC as a potent target for combating chondrocyte ferroptosis in BP-3-associated osteoarthritis.

A preoperative package of care for osteoarthritis, consisting of weight loss, orthotics, rehabilitation, and topical and oral analgesia (OPPORTUNITY): a two-centre, open-label, randomised controlled feasibility trial

BACKGROUND

Osteoarthritis of the knee is a major cause of disability worldwide. Non-operative treatments can reduce the morbidity but adherence is poor. We hypothesised that adherence could be optimised if behavioural change was established in the preoperative period. Therefore, we aimed to assess feasibility, acceptability, and recruitment and retention rates of a preoperative package of non-operative care in patients awaiting knee replacement surgery.

METHODS

We did an open-label, randomised controlled, feasibility trial in two secondary care centres in the UK. Eligible participants were aged 15-85 years, on the waiting list for a knee arthroplasty for osteoarthritis, and met at least one of the thresholds for one of the four components of the preoperative package of non-operative care intervention (ie, weight loss, exercise therapy, use of insoles, and analgesia adjustment). Participants were randomly assigned (2:1) to either the intervention group or the standard of care (ie, control) group. All four aspects of the intervention were delivered weekly over 12 weeks. Participants in the intervention group were reviewed regularly to assess adherence. The primary outcome was acceptability and feasibility of delivering the intervention, as measured by recruitment rate, retention rate at follow-up review after planned surgery, health-related quality of life, joint-specific scores, and adherence (weight change and qualitative interviews). This study is registered with ISRCTN, ISRCTN96684272.

FINDINGS

Between Sept 3 2018, and Aug 30, 2019, we screened 233 patients, of whom 163 (73%) were excluded and 60 (27%) were randomly assigned to either the intervention group (n=40) or the control group (n=20). 34 (57%) of 60 participants were women, 26 (43%) were men, and the mean age was 66·8 years (SD 8·6). Uptake of the specific intervention components varied: 31 (78%) of 40 had exercise therapy, 28 (70%) weight loss, 22 (55%) analgesia adjustment, and insoles (18 [45%]). Overall median adherence was 94% (IQR 79·5-100). At the final review, the intervention group lost a mean of 11·2 kg (SD 5·6) compared with 1·3 kg (3·8) in the control group (estimated difference -9·8 kg [95% CI -13·4 to -6·3]). A clinically significant improvement in health-related quality o life (mean change 0·078 [SD 0·195]) were reported, and joint-specific scores showed greater improvement in the intervention group than in the control group. No adverse events attributable to the intervention occurred.

INTERPRETATION

Participants adhered well to the non-operative interventions and their health-related quality of life improved. Participant and health professional feedback were extremely positive. These findings support progression to a full-scale effectiveness trial.

FUNDING

Versus Arthritis.

Safety and Efficacy of Hybrid Cooperative Complexes of Sodium Hyaluronate and Sodium Chondroitin for the Treatment of Patients with Symptomatic Knee Osteoarthritis

INTRODUCTION

Knee osteoarthritis (KOA) represents a widespread degenerative disease that causes pain and motor disability. Conservative treatments mainly focus on relieving symptoms, improving joint function, and trying to delay surgery. Safety and efficacy of hybrid cooperative complexes (2.4% sodium hyaluronate and 1.6% sodium chondroitin; HA-SC) for symptomatic KOA were investigated in a single-arm, prospective, pilot study.

METHODS

Patients with a visual analogue scale (VAS) pain score ≥ 4 and Kellgren-Lawrence Grade < 4 received a single intraarticular HA-SC injection. Patients with a VAS score change from baseline ≤ 1 received a second injection at day 30. Device-related adverse events (DR-AEs)/adverse events (AEs) were primary endpoints. Secondary endpoints included Western Ontario and McMaster Universities Osteoarthritis Index LK 3.1 (WOMAC LK 3.1), VAS, patient global assessment of disease status (PtGA), and patient proportion needing a second injection.

RESULTS

Of 83 patients with KOA (Kellgren-Lawrence Grade, 2-3), 34.9% had DR-AEs at day 7. No serious DR-AEs/AEs were reported. A significant (P < 0.0001) reduction over time in VAS pain score plus WOMAC pain, stiffness, physical function limitation, and total scores was reported. Median PtGA scores indicated a 'slight improvement' at most follow-up visits. Only 18.1% of patients required a second injection.

CONCLUSIONS

A single intraarticular HA-SC injection was safe, well-tolerated, and did not lead to major deterioration in terms of reducing knee pain, stiffness, and physical function limitation in patients with symptomatic KOA.

Telerehabilitation consultations with a physiotherapist for chronic knee pain versus in-person consultations in Australia: the PEAK non-inferiority randomised controlled trial

BACKGROUND

Telerehabilitation whether perceived as less effective than in-person care for musculoskeletal problems. We aimed to determine if physiotherapy video conferencing consultations were non-inferior to in-person consultations for chronic knee pain.

METHODS

In this non-inferiority randomised controlled trial, we recruited primary care physiotherapists from 27 Australian clinics. Using computer-generated blocks, participants with chronic knee pain consistent with osteoarthritis were randomly assigned (1:1, stratified by physiotherapist and clinic) in-person or telerehabilitation (ie, video conferencing) physiotherapist consultations. Participants and physiotherapists were unmasked to group assignment. Both groups had five consultations over 3 months for strengthening, physical activity, and education. Primary outcomes were knee pain (on a numerical rating scale of 0-10) and physical function (using the Western Ontario and McMaster Universities osteoarthritis index of 0-68) at 3 months after randomisation. Primary analysis was by modified intention-to-treat using all available data. This trial is registered with the Australian and New Zealand Clinical Trials Registry, ACTRN12619001240134.

FINDINGS

Between Dec 10, 2019, and June 17, 2022, 394 adults were enrolled, with 204 allocated to in-person care and 190 to telerehabilitation. 15 primary care physiotherapists were recruited. At 3 months, 383 (97%) participants provided information for primary outcomes and both groups reported improved pain (mean change 2·98, SD 2·23 for in-person care and 3·14, 1·87 for telerehabilitation) and function (10·20, 11·63 and 10·75, 9·62, respectively). Telerehabilitation was non-inferior for pain (mean difference 0·16, 95% CI -0·26 to 0·57) and function (1·65, -0·23 to 3·53). The number of participants reporting adverse events was similar between groups (40 [21%] for in-person care and 35 [19%] for telerehabilitation) and none were serious.

INTERPRETATION

Telerehabilitation with a physiotherapist is non-inferior to in-person care for chronic knee pain.

FUNDING

National Health and Medical Research Council.

A Cross-Sectional Study of Factors Predicting the Duration of the Efficacy of Viscosupplementation in Knee Osteoarthritis

Background: An advanced radiological stage and obesity are predictive of poorer and shorter responses to viscosupplementation in patients with knee osteoarthritis (OA). Very little is known regarding the impact of other factors such as sport practice, comorbidities, or anatomical features of OA. Methods: This study aimed to investigate patients' and OA characteristics associated with the duration of the effectiveness (DE) of viscosupplementation in patients with knee OA. It was a cross-sectional, single-centre clinical trial in patients with knee OA treated with intra-articular (IA) hyaluronic acid (HA) injection(s) within the previous 3 years. The investigators collected data regarding demographic and radiographic features (Kellgren-Lawrence grade and involved knee compartments), dosing regimen (single or repeat injections), the presence and volume of joint effusion, previous or concomitant IA corticosteroid injection, the number of previous viscosupplementations, and comorbidities. Patients completed a questionnaire including the self-assessment of DE (the number of weeks during which viscosupplementation was effective on symptoms), the activity level (sedentary, active, or athletic), and the level of sport activity (light, moderate, or intensive). Predictors of the DE were studied in bivariate and multivariate analyses. Results: In total, 105 patients (149 knees) were analysed (62% women, mean age 66.1 ± 13.2 years, mean BMI 27.5 ± 7.5 kg/m2). The mean DE was 48.2 ± 24.8 weeks. In bivariate analysis, the predictors of a shorter DE were BMI > 27.5 kg/m2, more than three previous viscosupplementations, Kellgren-Lawrence grade 4, sedentary patients, and multicompartmental involvement. In the multivariate analysis, four independent factors remained associated with a shorter DE: BMI > 27.5 kg/m2, multicompartmental knee involvement, number of viscosupplementations >3, and sedentary lifestyle. A statistically significant association between a longer DE and arterial hypertension was found, suggesting a beneficial effect of certain antihypertensive medications. Conclusions: This study confirms that being overweight significantly reduces the duration of the effectiveness of viscosupplementation. It also shows that viscosupplementation is more lastingly effective in unicompartmental OA and among active or athletic patients. The duration of effectiveness decreases when the treatment is repeated more than three times.

Phenome-wide causal associations between osteoarthritis and other complex traits through the latent causal variable analysis

BACKGROUND

Individuals with osteoarthritis present with comorbidities, and the potential causal associations remain incompletely elucidated. The present study undertook a large-scale investigation about the causality between osteoarthritis and variable traits, using the summary-level data of genome-wide association studies (GWAS).

METHODS

The present study included the summary-level GWS data of knee osteoarthritis, hip osteoarthritis, hip or knee osteoarthritis, hand osteoarthritis, and other 1355 traits. Genetic correlation analysis was conducted between osteoarthritis and other traits through cross-trait bivariate linkage disequilibrium score regression. Subsequently, latent causal variable analysis was performed to explore the causal association when there was a significant genetic correlation. Genetic correlation and latent causal variable analysis were conducted on the Complex Traits Genomics Virtual Lab platform ( https://vl.genoma.io/ ).

RESULTS

We found 133 unique phenotypes showing causal relationships with osteoarthritis. Our results confirmed several well-established risk factors of osteoarthritis, such as obesity, weight, BMI, and meniscus derangement. Additionally, our findings suggested putative causal links between osteoarthritis and multiple factors. Socioeconomic determinants such as occupational exposure to dust and diesel exhaust, extended work hours exceeding 40 per week, and unemployment status were implicated. Furthermore, our analysis revealed causal associations with cardiovascular and metabolic disorders, including heart failure, deep venous thrombosis, type 2 diabetes mellitus, and elevated cholesterol levels. Soft tissue and musculoskeletal disorders, such as hallux valgus, internal derangement of the knee, and spondylitis, were also identified to be causally related to osteoarthritis. The study also identified the putative causal associations of osteoarthritis with digestive and respiratory diseases, such as Barrett's esophagus, esophagitis, and asthma, as well as psychiatric conditions including panic attacks and manic or hyperactive episodes. Additionally, we observed osteoarthritis causally related to pharmacological treatments, such as the use of antihypertensive medications, anti-asthmatic drugs, and antidepressants.

CONCLUSION

Our study uncovered a wide range of traits causally associated with osteoarthritis. Further studies are needed to validate and illustrate the detailed mechanism of those causal associations.

Factors associated with medial meniscal extrusion in non-osteoarthritic knees with medial meniscus tears: A cross-sectional study

BACKGROUND

Medial meniscal extrusion (MME) plays an important role in the progression of knee osteoarthritis. Exploring the factors associated with MME in non-osteoarthritic knees may assist in the prevention of osteoarthritis.

OBJECTIVE

To identify the factors associated with pathologic MME in non-osteoarthritic knees with medial meniscus tears (MMTs).

DESIGN

A cross-sectional study.

PARTICIPANTS

One hundred fifty patients with non-osteoarthritic knees who underwent arthroscopic surgery for MMT. Patients were divided into a pathologic MME group (n = 54) and a control group (n = 96) based on whether a pathologic MME was present on magnetic resonance (MR) images.

SETTING

Tertiary medical institution.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

The MME distance was measured on a coronal MR image obtained at the midpoint of the medial femoral condyle. An MME distance ≥3 mm was considered to indicate pathologic MME. Demographic and clinical data were collected as variables. Multivariable logistic regression analysis was performed to identify factors associated with pathologic MME.

RESULTS

After multivariable adjustment, body mass index (BMI) and the type of MMT were associated significantly with pathologic MME in the multivariable logistic regression model. Each unit higher in BMI was associated with a 13% higher risk of pathologic MME (odds ratio [OR] 1.13, 95% confidence interval [CI] 1.01-1.28, p = .04). The odds of pathologic MME were approximately four times and three times higher for radial tears (OR 4.34, 95% CI 1.25-15.03, p = .02) and complex tears (OR 3.07, 95% CI 1.17-8.05, p = .02) than for horizontal and longitudinal tears.

CONCLUSIONS

BMI and the type of MMT were independent factors associated with pathologic MME in non-osteoarthritic knees with MMT. A higher BMI, radial tears, and complex tears were predisposed to pathologic MME.

Increasing Burden of Osteoarthritis in China: Trends and Projections from the Global Burden of Disease Study 2019

BACKGROUND This study aimed to evaluate the epidemiology of osteoarthritis in China in a comprehensive and reliable way, to project its future epidemiological patterns, and to mitigate its health hazards. MATERIAL AND METHODS Data were extracted and analyzed from the Global Burden of Diseases Study 2019. Trends in osteoarthritis epidemiology were explored using joinpoint regression analysis. Additionally, we analyzed dynamic trends using the sociodemographic index (SDI) of China. To assess and predict the epidemiology of osteoarthritis from 2020 to 2039, we used both the Bayesian age-period-cohort model and Nordpred model. RESULTS The number of prevalent cases, incident cases, and years lived with disability (YLDs) for osteoarthritis in China increased from 51.8, 4.6, and 1.8 million, respectively, in 1990, to 132.8, 10.7, and 4.7 million, respectively, in 2019, and the average annual percentage changes were 3.286, 2.938, and 3.324, respectively. The prevalence and YLDs peaked in the population aged over 90 years old, while the incidence peaked in the population aged around 50 years old. A significant positive correlation was found between osteoarthritis burden and SDI. Osteoarthritis burden is expected to continue to increase. In the population studied here, it was higher in women than in men, but this may invert by 2039. CONCLUSIONS The prevalence, incidence, and YLDs of osteoarthritis had significantly increased and may continue to increase during the next 2 decades. Prevention and treatment strategies should target women, middle-aged individuals, and the elderly.

Nitric oxide-scavenging hyaluronic acid nanoparticles for osteoarthritis treatment

Osteoarthritis (OA) is a degenerative arthritis disease marked by inflammation, pain, and cartilage deterioration. Elevated nitric oxide (NO) levels play a pivotal role in mediating OA-related inflammation and are found in abundance within OA joints. This study introduces a NO-scavenging hyaluronic acid conjugate (HA-NSc) bearing both lubrication and anti-inflammatory properties for the treatment of osteoarthritis. For this, a derivative of o-phenylenediamine (o-PD) with good NO-scavenging capability (NSc) is designed, synthesized and chemically conjugated to HA. Owing to the amphiphilicity, this as-synthesized HA-NSc conjugate formed self-assembled nanoparticles (HA-NSc NPs) under aqueous conditions. When treated with activated murine macrophage RAW 264.7 cells that produce high levels of NO, these nanoparticles effectively reduced intracellular NO concentrations and inflammatory cytokines. In an OA animal model, the HA-NSc NPs significantly alleviated pain and diminished the cartilage damage due to the combined lubricating property of HA and NO-scavenging ability of NSc. Overall, the results from the study suggest HA-NSc NPs as a dual-action therapeutic agent for the treatment of OA by alleviating pain, inflammation, and joint damage, and also positioning the HA-NSc NPs as a promising candidate for innovative treatment of OA.

Dropout From Exercise Interventions in Adults With Knee or Hip Osteoarthritis: A Systematic Review and Meta-analysis

OBJECTIVE

To investigate the prevalence and moderators of dropout rates among adults with knee or hip osteoarthritis participating in exercise randomized controlled trials (RCTs).

DATA SOURCES

Two authors searched Embase, CINAHL, PsycARTICLES, and PubMed up to 01/09/2023.

STUDY SELECTION

We included RCTs of exercise interventions in people with knee or hip osteoarthritis that reported dropout rates.

DATA EXTRACTION

Dropout rates from exercise and control conditions and exerciser/participant, provider, and design/implementation related moderators.

DATA SYNTHESIS

In total, 209 RCTs involving 277 exercise arms in 13,102 participants were included (mean age at study level=64 years; median prevalence of men participants=26.8%). The trim-and-fill-adjusted prevalence of dropout across all RCTs was 17.5% (95% CI=16.7%-18.2%), which is comparable with dropout observed in control conditions (trim-and-fill-adjusted odds ratio=0.89; 95% CI=0.71-1.12, P=.37). Higher prevalence of antidepressant use at study-level predicted higher dropout (R2=0.75, P=.002, N RCTs=6, n exercisers=412). Supervision by an exercise professional was associated with lower dropout rates, with a trim-and-fill-adjusted rate of 13.2% (95% CI=11.7%-14.9%) compared with 20.8% without supervision (95% CI=18.3%-23.5%) (P<.001).

CONCLUSIONS

Dropout rates for exercise in RCTs are comparable with control conditions, suggesting that exercise is a generally well-accepted intervention. However, interventions should be supervised by an exercise professional, such as a physiotherapist or exercise physiologist, to further minimize the risk of dropout. Health professionals should consider participants' use of antidepressants as a risk factor for dropout from exercise.

Association between higher triglyceride glucose index and increased risk of osteoarthritis: data from NHANES 2015-2020

BACKGROUND

The relationship between the triglyceride glucose (TyG) index and osteoarthritis (OA) remains unclear. The objective of this study was to examine potential associations between an elevated TyG index and an increased risk of OA prevalence.

METHODS

3,921 participants with OA from the National Health and Nutrition Examination Survey (2015-2020) were included in this study. Participants were categorized into quartiles based on TyG index, which was determined using the formula: Ln [triglyceride (mg/dL) fasting blood glucose (mg/dL)/2]. Weighted multivariable regression, subgroup analyses, and threshold effect analyses were performed to calculate the independent association between TyG index and OA.

RESULTS

A total of 25,514 people were enrolled, with a mean TyG index of 8.48 ± 0.65. The results of multivariable logistic regression analysis after full adjustment showed a significant association between higher TyG index values and an increased risk of OA. Specifically, each incremental unit increase in the TyG index was associated with a 634% higher risk of OA [OR = 7.34; 95% CI: 2.25, 23.93; p = 0.0010]. Based on interaction tests, age, gender, BMI, and smoking status did not significantly affect the relationship between the TyG index and OA, while diabetes showed a stronger positive correlation between the TyG index and OA.

CONCLUSION

An increased risk of OA was associated with a higher TyG index. TyG could be a valuable predictor of OA and offer novel perspectives on the assessment and treatment of OA.

Knee Measurement System with Osteoarthritis Levels Using Artificial Cartilage and Skeletons

Knee osteoarthritis (OA), also known as degenerative arthritis, is a disease characterized by irreversible changes in the cartilage and bones comprising the joints, resulting in pain, impaired function, and deformity. Furthermore, independent of natural aging, the rate of change in joint cartilage has increased in recent years, which is mainly attributed to environmental factors. The rising incidence of knee-related disorders emphasizes the importance of analyzing the morphology and kinematics of knee structure. This study introduces a knee measurement system designed to replicate the motions of knee using 3D-printing technology, providing insights into knee mechanics with OA level. The research explores the stages of OA using the Kellgren-Lawrence (KL) grade scale, highlighting the variations in the force applied to the knee bone according to movement. The developed knee-simulation system, utilizing the four-bar-link theory, presents a novel approach to studying OA levels 0 to 4. As OA progresses, the cartilage deteriorates, affecting the movement of OA. The OA-based knee measurement system that incorporates soft tissues and skeletons can assist in developing a personalized diagnostic approach for knee disease. This will also help to enhance surgical effectiveness by facilitating the creation of personalized prosthetic joints for individual patients and offering a customized surgical simulation.

Pitfalls and pearls in diagnosing inflammatory arthritis in older patients

Given current demographic shifts, the number of older adults continues to grow, with almost half of patients over 65 being diagnosed with some form of arthritis. Rheumatic diseases pose unique diagnostic challenges in older patients due to the convergence of physiologic changes of aging, confounding difficulties to care, and atypical disease manifestations. This review summarizes the current published evidence to guide clinicians in evaluating geriatric patients with rheumatologic concerns, focusing on inflammatory arthritis. Using the background of epidemiologic data on various musculoskeletal diseases, clinical presentations, current diagnostic tests, and known physiologic changes of aging, this review highlights five diagnostic pitfalls in inflammatory polyarthritis among older patients. The pitfalls include: 1) broader differential diagnosis; 2) atypical presentations; 3) communication, cognitive, and social impairments; 4) the role of chronological vs. biological age; and 5) anchoring bias by assuming older adults are simply "older young adults". These pitfalls are discussed in the context of geriatric principles such as the "hallmarks of aging" and the expected pathophysiologic changes of organ systems. Furthermore, the review discusses the strengths and weaknesses of diagnostic tests used in arthritis and introduces some of the geriatric assessment tools that systematically evaluate multimorbidity and geriatric syndromes. With familiarity of the potential diagnostic pitfalls, knowledge of both normal and pathologic aging processes, awareness of the difference between biological and chronological age, and the ability to use geriatric assessment tools to better characterize older patients, clinicians will be better able to diagnose and manage rheumatic conditions in this population.

Sphingolipid-Induced Bone Regulation and Its Emerging Role in Dysfunction Due to Disease and Infection

The human skeleton is a metabolically active system that is constantly regenerating via the tightly regulated and highly coordinated processes of bone resorption and formation. Emerging evidence reveals fascinating new insights into the role of sphingolipids, including sphingomyelin, sphingosine, ceramide, and sphingosine-1-phosphate, in bone homeostasis. Sphingolipids are a major class of highly bioactive lipids able to activate distinct protein targets including, lipases, phosphatases, and kinases, thereby conferring distinct cellular functions beyond energy metabolism. Lipids are known to contribute to the progression of chronic inflammation, and notably, an increase in bone marrow adiposity parallel to elevated bone loss is observed in most pathological bone conditions, including aging, rheumatoid arthritis, osteoarthritis, and osteomyelitis. Of the numerous classes of lipids that form, sphingolipids are considered among the most deleterious. This review highlights the important primary role of sphingolipids in bone homeostasis and how dysregulation of these bioactive metabolites appears central to many chronic bone-related diseases. Further, their contribution to the invasion, virulence, and colonization of both viral and bacterial host cell infections is also discussed. Many unmet clinical needs remain, and data to date suggest the future use of sphingolipid-targeted therapy to regulate bone dysfunction due to a variety of diseases or infection are highly promising. However, deciphering the biochemical and molecular mechanisms of this diverse and extremely complex sphingolipidome, both in terms of bone health and disease, is considered the next frontier in the field.

Evaluation of Osteoarthritis Disease Burden in China During 1990-2019 and Forecasting Its Trend Over the Future 25 Years

OBJECTIVE

This study aimed to estimate the temporal trend of osteoarthritis (OA) burden in China by age, sex, and joint sites from 1990 to 2019 and predict the long-term trend over the next 25 years.

METHODS

Using data from the Global Burden of Disease Study 2019, we estimated incident cases, prevalent cases, disability-adjusted life years (DALYs) of OA, and DALYs of OA attributed to high body mass index (BMI), as well as corresponding age-standardized rates (ASRs) for aforementioned indicies. Estimated annual percentage change (EAPC) and Nordpred age-period-cohort model were used to describe temporal trend changes and predict future disease burden.

RESULTS

From 1990 to 2019, the ASR of OA incidence increased from 472.53 per 100,000 to 509.84 per 100,000 people (EAPC: 0.36, 95% confidence interval [CI] 0.29-0.44); the ASR of OA prevalence increased from 5,880.58 per 100,000 to 6,330.06 per 100,000 people (EAPC 0.35, 95% CI 0.28-0.42); the ASR of OA DALYs increased from 206.38 per 100,000 to 224.78 per 100,000 people (EAPC 0.40, 95% CI 0.32-0.48). The ASR of OA DALYs attributed to high BMI increased rapidly, especially in men and patients with hip OA. Projections suggest an increasing trend in the incidence, prevalence, and DALYs of OA from 2019 to 2044, with the prevalent cases and DALYs of OA in China expected to increase by approximately 1.5 times over the next 25 years.

CONCLUSION

The disease burden of OA has increased in China over the past 30 years and is expected to continue rising over the next 25 years.

Physiotherapeutic Intervention Techniques for Knee Osteoarthritis: A Systematic Review

Globally, knee osteoarthritis (KOA) is the leading cause of disability. The most prevalent complaints associated with KOA are knee pain, joint stiffness, and weakness in the muscles of the lower limbs. These symptoms impede movement and result in functional limitations. As a result, people with KOA have a lower quality of life. For all patient groups with knee OA, an effective rehabilitation program focuses on improving knee range of motion, isometric quadriceps strength, and productivity level while reducing discomfort. The American College of Rheumatology (ACR) categorization criteria for KOA, research on KOA physiotherapy, and reviews covering various physical therapy interventions, including exercise, physical modalities, and patient education, were used to narrow down the pool of 180 systematic reviews to 15 articles. Google Scholar, PubMed, the Cochrane Library, and EMBASE were the databases that were used. The following keyword combinations were included in our search: KOA and physiotherapy or interventions or exercises, strengthening and stretching, concentric and eccentric training. Through our analysis, we identified a few methods that, in addition to standard therapy, could be used in clinical settings for people with osteoarthritis in the knee. It has been shown that Mulligan, Pilates, Kinesiotaping, Aquatic Therapy, and other current therapies are effective. The study employed a broad range of results. This review concludes that rather than relying solely on conventional therapy, it is preferable to combine a number of the most current physiotherapy techniques with it.

Tanshinone IIA attenuates osteoarthritis via inhibiting aberrant angiogenesis in subchondral bone

Excessive angiogenesis in subchondral bone is a pathological feature of osteoarthritis (OA). Tanshinone IIA (TIIA), an active compound found in Salvia miltiorrhiza, demonstrates significant anti-angiogenic properties. However, the effect of TIIA on abnormal subchondral angiogenesis in OA is still unclear. This study aims to investigate the mechanism of TIIA in modulating subchondral bone angiogenesis during OA and assess its therapeutic potential in OA. Our findings demonstrate that TIIA attenuated articular cartilage degeneration, normalized subchondral bone remodeling, and effectively suppressed aberrant angiogenesis within subchondral bone in monosodium iodoacetate (MIA)-induced OA mice. Additionally, the angiogenesis capacity of primary CD31hiEmcnhi endothelial cells was observed to be significantly reduced after treatment with TIIA in vitro. Mechanically, TIIA diminished the proportion of hypertrophic chondrocytes, ultimately leading to a substantial reduction in the secretion of vascular endothelial growth factor A (VEGFA). The supernatant of hypertrophic chondrocytes promoted the tube formation of CD31hiEMCNhi endothelial cells, whereas TIIA inhibited this process. Furthermore, TIIA effectively suppressed the expression of vascular endothelial growth factor receptor 2 (VEGFR2) along with its downstream MAPK pathway in CD31hiEmcnhi endothelial cells. In conclusion, our data indicated that TIIA could effectively inhibit the abnormal angiogenesis in subchondral bone during the progression of OA by suppressing the VEGFA/VEFGR2/MAPK pathway. These findings significantly contribute to our understanding of the abnormal angiogenesis in OA and offer a promising therapeutic target for OA treatment.

Shorter length of stay and significant cost savings with ambulatory surgery primary unilateral total knee arthroplasty in Asians using enhanced recovery protocols

Introduction

Enhanced recovery after surgery (ERAS) in total knee arthroplasty (TKA) has reduced the length of stay (LOS) and cost of TKA in the Western population. Asians had been identified to be at higher odds of non-home discharge following TKA due to cultural differences. The efficacy of ERAS in TKA for Asian patients is less known. We aimed to investigate the efficacy of ERAS in reducing the LOS, transition to ambulatory surgery, improving home discharges, and reducing cost in an Asian population following TKA.

Methods

Retrospective analysis was performed on 634 TKA patients in 2017 (pre- ERAS) and 584 TKA patients who had undergone ERAS in 2022 in a tertiary hospital.

Results

Patients in 2022 (ERAS) were older (69 ± 7 vs. 68 ± 7 years old, p < 0.001) and had a higher proportion of patients with poorer function (p < 0.001). The LOS reduced from 5.4 days (95% CI:5.2-5.6) to 2.9 days (95% CI:2.7-3.2) (p < 0.001) with about 49 % of patients transitioning to ambulatory surgery and having a LOS of 1.4 days (95 %CI:1.3-1.5). The proportion of patients being discharged home in 2022 (78.9 %) was higher compared to 2017 (62.2 %) (p < 0.001). This saved the hospital 1817.4 inpatient ward bed days, which translated to S$2,124,540.60 of cost saving in a year, and up to S$2397.28 for the individual patient.

Conclusion

ERAS after TKA was able to safely achieve LOS comparable to the western population and allowed transition to ambulatory knee replacement in the Asian population. Consequently, this led to higher proportion of home discharges and achieved significant cost saving and hospital bed days.

Epidemiology of osteoarthritis: literature update 2022-2023

PURPOSE OF REVIEW

This review highlights recently published studies on osteoarthritis (OA) epidemiology, including topics related to understudied populations and joints, imaging, and advancements in artificial intelligence (AI) methods.

RECENT FINDINGS

Contemporary research has improved our understanding of the burden of OA in typically understudied regions, including ethnic and racial minorities in high-income countries, the Middle East and North Africa (MENA) and Latin America. Efforts have also been made to explore the burden and risk factors in OA in previously understudied joints, such as the hand, foot, and ankle. Advancements in OA imaging techniques have occurred alongside the developments of AI methods aiming to predict disease phenotypes, progression, and outcomes.

SUMMARY

Continuing efforts to expand our knowledge around OA in understudied populations will allow for the creation of targeted and specific interventions and inform policy changes aimed at reducing disease burden in these groups. The burden and disability associated with OA is notable in understudied joints, warranting further research efforts that may lead to effective therapeutic options. AI methods show promising results of predicting OA phenotypes and progression, which also may encourage the creation of targeted disease modifying OA drugs (DMOADs).

Global burden of early-onset osteoarthritis, 1990-2019: results from the Global Burden of Disease Study 2019

OBJECTIVES

Early-onset osteoarthritis (OA) is an emerging health issue amidst the escalating prevalence of overweight and obesity. However, there are scant data on its disease, economic burden and attributable burden due to high body mass index (BMI).

METHODS

Using data from the Global Burden of Diseases Study 2019, we examined the numbers of incident cases, prevalent cases, years lived with disability (YLDs) and corresponding age-standardised rates for early-onset OA (diagnosis before age 55) from 1990 to 2019. The case definition was symptomatic and radiographically confirmed OA in any joint. The average annual percentage changes (AAPCs) of the age-standardised rates were calculated to quantify changes. We estimated the economic burden of early-onset OA and attributable burden to high BMI.

RESULTS

From 1990 to 2019, the global incident cases, prevalent cases and YLDs of early-onset OA were doubled. 52.31% of incident OA cases in 2019 were under 55 years. The age-standardised rates of incidence, prevalence and YLDs increased globally and for countries in all Sociodemographic Index (SDI) quintiles (all AAPCs>0, p<0.05), with the fastest increases in low-middle SDI countries. 98.04% of countries exhibited increasing trends in all age-standardised rates. Early-onset OA accounts for US$46.17 billion in healthcare expenditure and US$60.70 billion in productivity loss cost in 2019. The attributable proportion of high BMI for early-onset OA increased globally from 9.41% (1990) to 15.29% (2019).

CONCLUSIONS

Early-onset OA is a developing global health problem, causing substantial economic costs in most countries. Targeted implementation of cost-effective policies and preventive intervention is required to address the growing health challenge.

Qualitative and Quantitative Measures in the Infrapatellar Fat Pad in Older Adults: Associations with Knee Pain, Radiographic Osteoarthritis, Kinematics, and Kinetics of the Knee

RATIONALE AND OBJECTIVES

The purpose of this study is to delineate cross-sectional associations between qualitative and quantitative measures of the infrapatellar fat pad (IPFP) and knee symptoms, structure, kinematics, and kinetics in older adults.

METHODS

Ninety eligible subjects (90 knees, mean age 54.0 years, 68.9% female) were examined at our center. We used T2-weighted fat-suppressed magnetic resonance imaging (MRI) to evaluate signal intensity alteration, maximum sagittal area, and depth of the IPFP. Symptomatic osteoarthritis (SOA) was a pain subscale score greater than 0 on the Western Ontario McMaster Osteoarthritis Index. A Kellgren-Lawrence grade ≥ 2 identified incident radiographic osteoarthritis (iROA). Three-dimensional gait data were employed to analyze knee joint kinematics and kinetics. Correlation and regression analyzes assessed associations between IPFP measurements and SOA, iROA, kinematics, and kinetics.

RESULTS

There were strong and positive associations between IPFP signal intensity alteration and both SOA and iROA in multivariable regression analyzes [OR (95% CI): 2.849 (1.440 to 5.636), 2.356 (1.236 to 4.492), respectively]. Conversely, a significant negative correlation was observed between IPFP maximum area and flexion angle [B (95%CI): - 1.557 (-2.549 to -0.564)]. Moreover, adjusting for covariates did not reveal any significant correlation between IPFP parameters and other indicators (P > 0.05, respectively).

CONCLUSION

IPFP signal intensity alteration and area were associated with knee clinical symptoms, structural abnormalities, and flexion angle in adults over 40, respectively. These findings suggest that IPFP may be a crucial imaging biomarker in early and middle knee osteoarthritis.

Musculoskeletal imaging of senescence

Senescent cells play a vital role in the pathogenesis of musculoskeletal (MSK) diseases, such as chronic inflammatory joint disorders, rheumatoid arthritis (RA), and osteoarthritis (OA). Cellular senescence in articular joints represents a response of local cells to persistent stress that leads to cell-cycle arrest and enhanced production of inflammatory cytokines, which in turn perpetuates joint damage and leads to significant morbidities in afflicted patients. It has been recently discovered that clearance of senescent cells by novel "senolytic" therapies can attenuate the chronic inflammatory microenvironment of RA and OA, preventing further disease progression and supporting healing processes. To identify patients who might benefit from these new senolytic therapies and monitor therapy response, there is an unmet need to identify and map senescent cells in articular joints and related musculoskeletal tissues. To fill this gap, new imaging biomarkers are being developed to detect and characterize senescent cells in human joints and musculoskeletal tissues. This review article will provide an overview of these efforts. New imaging biomarkers for senescence cells are expected to significantly improve the specificity of state-of-the-art imaging technologies for diagnosing musculoskeletal disorders.