To systematically summarize the mechanism of action, current clinical application status, efficacy characteristics and research progress of platelet-rich plasma (PRP) in the treatment of osteoarthritis, so as to provide references for clinical decision-making in the fields of rheumatology and orthopedics.

Databases including PubMed, CNKI and Wanfang at home and abroad in the recent 5 years were retrieved. With the keywords of "PRP, osteoarthritis, cartilage repair, intra-articular injection, clinical efficacy", literature screening and induction were performed. A comprehensive review and analysis were conducted on the preparation methods, mechanism of action, therapeutic effects on osteoarthritis in different sites, comparison with traditional treatments and safety issues of PRP.

PRP releases a variety of growth factors through high-concentration platelets, which can promote chondrocyte proliferation and extracellular matrix synthesis, inhibit local inflammatory response and reduce synovial inflammation, thus delaying the progression of joint degeneration. Clinical studies have confirmed that intra-articular injection of PRP is most widely used in knee osteoarthritis, and also has good efficacy in osteoarthritis of the hip, ankle, interphalangeal and other sites. In particular, it is superior to traditional drugs such as sodium hyaluronate in relieving pain, improving joint function and long-term efficacy. Different preparation protocols, injection frequencies and whether combined with leukocytes have certain effects on the curative effect. Leukocyte-rich PRP and leukocyte-depleted PRP have their own applicable scenarios. In terms of safety, as an autologous biological agent, PRP has an extremely low incidence of severe adverse reactions, and most common adverse reactions are mild and transient. At present, there are still some problems in the research, such as inconsistent preparation standards, variable follow-up periods and insufficient large-sample, multi-center randomized controlled studies.

PRP has a clear mechanism, definite efficacy and high safety in the treatment of osteoarthritis, and has important clinical promotion value. In the future, it is necessary to further standardize the PRP preparation process, improve the individualized treatment plan, and conduct higher-quality clinical studies to promote its standardized application in the field of rheumatology.