Preventative and Disease-Modifying Investigations for Osteoarthritis Management Are Significantly Under-represented in the Clinical Trial Pipeline: A 2020 Review

Quadriceps Strength, Postural Stability, and Pain Mediation in Bilateral Knee Osteoarthritis: A Comparative Analysis with Healthy Controls

Bilateral knee osteoarthritis (OA) poses significant challenges to individuals' functional abilities, including quadriceps strength, postural stability, and pain perception. Understanding the complex relationships among these factors is crucial for enhancing knee OA management strategies. The primary objective of this research is to evaluate and draw comparisons between the strength of the quadriceps and the level of postural stability in two distinct groups: individuals afflicted with bilateral knee OA and those who are healthy. Furthermore, the study seeks to examine the potential correlation between the strength of the quadriceps and the level of postural stability in individuals with knee OA. In addition to this, an investigation into the potential mediating effect of pain on the relationship between these physiological factors will also be conducted. A total of 95 participants with bilateral knee OA and 95 healthy controls were recruited. Quadriceps strength was assessed using dynamometry and postural stability was evaluated through anterior-posterior and medial-lateral sway measurements along with the ellipse area using a force plate. Pain levels were measured using the Visual Analog Scale (VAS). Mediation analysis was employed to explore the role of pain in mediating the relationship between quadriceps strength and postural stability. Statistical analyses included t-tests, Pearson correlation coefficients, and mediation analysis. Knee OA participants exhibited significantly lower quadriceps strength (1.08 Nm/kg ± 0.54) compared to controls (1.54 Nm/kg ± 0.57, p < 0.001). They also demonstrated compromised postural stability with increased anterior-posterior sway (9.86 mm ± 3.017 vs. 2.98 mm ± 1.12, p < 0.001), medial-lateral sway (7.87 mm ± 2.23 vs. 3.12 mm ± 1.34, p < 0.001), and larger ellipse area (935.75 mm2 ± 172.56 vs. 436.19 mm2 ± 135.48, p < 0.001). Negative correlations were observed between quadriceps strength and postural stability variables (r = from -0.43 to -0.51, p < 0.001). Pain significantly mediated the relationship between quadriceps strength and postural stability variables (p < 0.05). This study highlights the associations between quadriceps strength, postural stability, and pain mediation in individuals with bilateral knee OA. Our findings emphasize the need for targeted interventions addressing quadriceps weakness and compromised postural stability. Additionally, the mediation effect of pain underscores the complexity of these relationships, offering insights for more effective management strategies.

Preclinical Use of FGF-18 Augmentation for Improving Cartilage Healing Following Surgical Repair: A Systematic Review

OBJECTIVE

To evaluate the efficacy of fibroblast growth factor-18 (FGF-18) augmentation for improving articular cartilage healing following surgical repair in preclinical (in vivo) animal models.

DESIGN

A systematic review was performed evaluating the efficacy of FGF-18 augmentation with cartilage surgery compared with cartilage surgery without FGF-18 augmentation in living animal models. Eligible intervention groups were FGF-18 treatment in conjunction with orthopedic procedures, including microfracture, osteochondral auto/allograft transplantation, and cellular-based repair. Outcome variables were: International Cartilage Repair Society (ICRS) score, modified O'Driscoll histology score, tissue infill score, qualitative histology, and adverse events. Descriptive statistics were recorded and summarized for each included study.

RESULTS

In total, 493 studies were identified and 4 studies were included in the final analysis. All studies were randomized controlled trials evaluating in vivo use of recombinant human FGF-18 (rhFGF-18). Animal models included ovine (n = 3) and equine (n = 1), with rhFGF-18 use following microfracture (n = 3) or osteochondral defect repair (n = 1). The rhFGF-18 was delivered via intra-articular injection (n = 2), collagen membrane scaffold (n = 1), or both (n = 1). All studies reported significant, positive improvements in cartilage defect repair with rhFGF-18 compared with controls based on ICRS score (n = 4), modified O'Driscoll score (n = 4), tissue infill (n = 3), and expression of collagen type II (n = 4) (P < 0.05). No adverse events were reported with the intra-articular administration of this growth factor, indicating short-term safety and efficacy of rhFGF-18 in vivo.

CONCLUSION

This systematic review provides evidence that rhFGF-18 significantly improves cartilage healing at 6 months postoperatively following microfracture or osteochondral defect repair in preclinical randomized controlled trials.

Biological Targets of Multimolecular Therapies in Middle-Age Osteoarthritis

Knee osteoarthritis (OA) is a common condition, prevalent in middle-agedness, associated with chronic pain and impaired quality of life. Two interrelated biological processes fuel early OA progression: inflammation and structural tissues catabolism. Procatabolic and proinflammatory mediators are interconnected and form part of a self-perpetuating loop. They leverage OA research complexity because of the impossibility to discern certain spatiotemporal tissues' changes from others. Both are shared targets of versatile regenerative multimolecular therapies. In particular, platelet-rich plasma can interfere with inflammation and inflammatory pain. The therapeutic approach is to alter the vicious inflammatory loop by modifying the molecular composition of the synovial fluid, thereby paracrine cellular cross talk. Intra-articular injections of platelet-rich plasma can provide key factors balancing proinflammatory and anti-inflammatory factors, targeting macrophage dysfunction and modulating immune mechanisms within the knee.

Acute Intervention With Selective Interleukin-1 Inhibitor Therapy May Reduce the Progression of Posttraumatic Osteoarthritis of the Knee: A Systematic Review of Current Evidence

PURPOSE

To evaluate the efficacy of selective interleukin (IL)-1 inhibitor therapy in the reduction of posttraumatic osteoarthritis (PTOA) progression following knee ligament or meniscal injury.

METHODS

A systematic review was conducted evaluating the disease-modifying efficacy of selective IL-1 inhibition in the setting of knee PTOA.

RESULTS

The literature search identified 364 articles and 11 studies were included (n = 10 preclinical, n = 1 clinical). Drug delivery in preclinical studies was administered using IL-1Ra-encoded helper-dependent adenovirus particles (n = 3), synovial cells transfected with an IL-1Ra-encoded retroviral vector (n = 3), or varying chemical compositions of nonviral microcapsule gene carriers (n = 4). Intervention with selective IL-1 inhibitor therapy within 2 weeks of injury provided the greatest protective benefits in reducing the progression of PTOA regardless of drug delivery methodology in preclinical models. The majority of studies reported significantly better cartilage integrity and reduction in lesion size in animals treated with gene therapy with the greatest effects seen in those treated within 5 to 7 days of injury.

CONCLUSIONS

Early intervention with selective IL-1 inhibitor therapy were effective in reducing proinflammatory IL-1β levels in the acute and subacute phases following traumatic knee injury in preclinical animal model studies, while significantly reducing cartilage damage, lesion size, and PTOA progression at short-term follow-up. However, it was found that the effect of these therapies diminished over time.

CLINICAL RELEVANCE

Acute, intra-articular injection of selective IL-1 inhibitors may reduce PTOA progression, supporting the need for additional basic and clinical investigation.

Projected number of osteoarthritis patients in Austria for the next decades - quantifying the necessity of treatment and prevention strategies in Europe

BACKGROUND

The present study aimed to predict the expected number of patients with osteoarthritis (OA) in Austria up to the year 2080.

METHODS

Demographic data and population projections between 2019 and 2080 were obtained from European authorities. Information about recent age- and sex-stratified prevalence of patients with self-reported physician-diagnosed OA was obtained from the Austrian Health Interview Survey (n = 15,771). Projections were stratified by age and sex; sensitivity analyses were performed based on aging, main (most likely), and growth scenarios of the population.

RESULTS

Based on the projection, the overall increase in the total number of patients with OA from 2019 to 2080 will be 38% for men and women. In 2019, the highest number of OA-patients nested in the groups of persons aged 70-79 (n = 238,749) and 60-69 (n = 237,729) years. In 2080, the 80+ age group is predicted to have the highest number of OA with 421,548 individuals (i.e. factor 3.45 and factor 2.48 increase in the male and female group, respectively, compared to 2019), followed by the group aged 70-79 with 314,617 individuals (factor 1.45 and factor 1.28 increase in the male and female group, respectively, compared to 2019). Similar trends were found in the ageing and growing scenarios.

CONCLUSIONS

The projected increase in the occurrence of OA will likely lead to a substantial socioeconomic burden for the Austrian healthcare system in the near and far future. The current findings plead for the development of sustainable concepts for the treatment and prevention of OA by European authorities.

Editorial Commentary: More Clinical Trials Should Focus on Primary Prevention of Osteoarthritis: Disruptive Thinkers Are Required

With increasing life expectancy and an increased prevalence of osteoarthritis, the total number of individuals with symptomatic degenerative arthritis will most likely increase considerably. The current focus of nonoperative treatment is on weight loss, exercise, muscle strengthening, physical therapy, nonsteroidal anti-inflammatory drugs, intra-articular injection therapies with corticosteroids, hyaluronic acid, or platelet-rich plasma, and lately, disease-modifying drugs. Obviously, prevention is better than cure, but only 5% of all studies registered on ClinicalTrials.gov in the United States are intending to develop strategies for prevention. The overall majority of included studies (89%) will target symptom resolution, and 6% will investigate disease-modifying drugs.