A narrative review of the progress in the treatment of knee osteoarthritis

Background and Objective: The pathogenesis of osteoarthritis (OA) involves a variety of complex mechanisms, including genetic, mechanical, metabolic, and inflammatory factors. There is evidence that inflammatory factors, abnormal chondrocyte apoptosis, and extracellular matrix degradation are closely associated with the occurrence and development of OA. The best treatment for OA is still controversial, but intra-articular injection is safer and more effective than non-surgical treatments, such as physical therapy and oral analgesics. This study sought to explore the mechanism, benefits, and adverse reactions of commonly used intra-articular injection therapy in the treatment of knee osteoarthritis (KOA). Methods: We analyzed the safety and adverse reactions of intra-articular injection in patients with KOA, and summarized the results. Key Content and Findings: Six weeks of the corticosteroid injection contributed to improve the symptoms of OA patients in short time. However, their symptoms did not improve significantly after this period. Using corticosteroids for a long time may result in oxidative stress, leading to adverse reactions, such as cartilage toxicity, and accelerate the progress of OA. Due to its high frequency, the local injection of hyaluronic acid can result in more adverse reactions when compared with the corticosteroids. Due to the lack of standardized factors for platelet-rich plasma (PRP) preparation, leukocyte-rich or leukocyte-free variants may be produced. Adverse reactions include injection-site pain, joint stiffness. Conclusions: Thus, it is necessary to promote further clinical trials to promote the clinical application of PRP.