Osteoarthritis

Placebo responses are prevalent in clinical trials for osteoarthritis, and they hinder the identification of effective new treatments. In this Review, Colloca and Neogi describe various aspects of the placebo phenomenon, and demonstrate how this knowledge can help to improve the design of clinical trials.

Cartilage defects often fail to heal, which can lead to degenerative changes and ultimately to osteoarthritis. This Review discusses various hypotheses for why articular cartilage fails to regenerate and accompanying potential therapeutic solutions.

Bone marrow lesions (BMLs) are considered possible biomarkers and therapeutic targets in osteoarthritis, but human studies of BMLs have important limitations. In this Review, the authors explore the utility and potential of animal models in BML research.

Matrix metalloproteinases contribute to irreversible joint remodelling in the pathogenesis of joint diseases, including rheumatoid arthritis and osteoarthritis. This article reviews several aspects of matrix metalloproteinase biology related to arthritis and discusses how they relate to opportunities for precision medicine and diagnosis.

In this Review, the authors discuss the similarities and differences between intervertebral disc degeneration and osteoarthritis of the facet joint and argue that both diseases should be viewed as being part of the same molecular disease spectrum.

Cartilage calcification is a hallmark of osteoarthritis. In this Review, the authors discuss the molecular mechanisms of calcium crystal formation in chondrocytes, the effects of crystals on cells in the joint, and potential targets for the treatment of osteoarthritis and other calcification disorders.

This Review examines the biology of synovial inflammation, the cell types involved, their interactions and the role of synovitis in the development and progression of osteoarthritis.

Erosive hand osteoarthritis is an aggressive condition with poor outcomes. In this Review, the authors describe the clinical features and risk factors associated with erosive hand osteoarthritis, and summarize progress in the areas of biomarkers, imaging, classification criteria and treatment.

The pathways involved in sensing and responding to mechanical stimuli have important roles in maintaining cartilage health, and can contribute to disease when dysregulated. This Review discusses cartilage mechanosignalling pathways and how they can be targeted to treat osteoarthritis.

In this Review, the authors introduce the application of artificial intelligence, in particular machine learning and deep learning, for improving multiple stages of MRI, including acquisition, processing and post-processing steps, for studying osteoarthritis.

Knee joint distraction (KJD) is used to stimulate joint repair in advanced osteoarthritis. In the Review, Jansen and Mastbergen provide an overview of the clinical trial results of KJD treatment, current knowledge of the molecular mechanisms underlying joint repair in KJD, and future directions and unanswered questions in KJD research and treatment.

In this Review, the authors assess the current understanding of symptomatic early-stage knee osteoarthritis, including its diagnosis and classification, and highlight important gaps in knowledge that will need to be addressed to enable effective management.

Given that intra-articular injections for the knee of treatments such as hyaluronic acid, stem cells and platelet-rich plasma are advised against or only weakly recommended by current clinical-practice guidelines, why do people continue to seek information about these treatments?

Osteoarthritis has many appearances and can stabilize or progress aggressively. However, there is not yet an aetiological classification of osteoarthritis subtypes. Can in silico approaches, despite difficulties in validation, help with the identification of experimentally challenging subtypes? And if they can, will these approaches translate to clinical benefits?

Successful, long-term treatment of articular cartilage injuries is important for the prevention of osteoarthritis but remains a major challenge. Three studies in 2022 highlight new approaches to improving articular cartilage regeneration.

Research related to the role of the synovium and its cell constituents during the pathogenies of osteoarthritis (OA) has taken a back seat to that of the cartilage and chondrocytes. The influence of synoviocytes in OA is increasingly recognized, but are synoviocytes equal in their contributions to disease progression?

Built by and for the research community, the Musculoskeletal Knowledge Portal (MSK-KP) offers researchers a single integrated platform on which to display, access, distill and explore results from large genomic and epigenomic studies to formulate hypotheses and accelerate the development of patient-centered therapeutics for complex, multi-factorial conditions such as osteoarthritis.