Abstract
Introduction: Bone diseases comprise a large group of common diseases, including fractures, osteoporosis, and osteoarthritis that affect a large number of individuals. Knee osteoarthritis (KOA) refers to a chronic joint disease characterized by degenerative lesions of the knee cartilage, causing pain, swelling, dyskinesia, and other symptoms of the knee joint. According to the World Health Organization (WHO), KOA has an incidence of approximately 10-15%, with the elderly population accounting for 95%. Objective: This was to conduct a systematic review to present state of the art, through randomized clinical trials and meta-analyses, of the treatment of knee osteoarthritis using platelet-rich plasma alone or in combination with bone marrow aspirate concentrate (stem cells and other cells), mesenchymal stem cells, hyaluronic acid, and corticosteroids. Methods: The systematic review rules of the PRISMA Platform were followed. The search was conducted from November 2024 to January 2025 in the Scopus, PubMed, Science Direct, Scielo, and Google Scholar databases. The quality of the studies was based on the GRADE instrument and the risk of bias was analyzed according to the Cochrane instrument. Results and Conclusion: A total of 126 articles were found, of which 39 articles were fully evaluated and 11 were included and developed in the present systematic review study. Considering the Cochrane tool for risk of bias, the overall assessment resulted in 31 studies with a high risk of bias and 22 studies that did not meet GRADE and AMSTAR-2. Most studies showed homogeneity in their results, with X2=79.9%>50%. The symmetrical funnel plot suggests no risk of bias among studies with small sample sizes. Based on the results, platelet-rich plasma demonstrated a significant advantage over hyaluronic acid, as well as improved symptom relief, lower reintervention rates, and pain improvement. At a minimum follow-up of 6 months, platelet-rich plasma has been shown to significantly improve pain and function in patients with knee osteoarthritis compared with placebo. Furthermore, platelet-rich plasma exhibited the highest values compared to bone marrow aspirate concentrate, hyaluronic acid, and corticosteroids. Furthermore, arthroscopically guided high-dose subchondral injection of primary synovial mesenchymal stem cells cultured in platelet-rich plasma and hyaluronic acid medium can regenerate cartilage defects, improving clinical outcomes. Meta-analyses have shown that the benefits of platelet-rich plasma injections are primarily apparent in the medium- to long-term management of clinical symptoms, including pain relief, improved quality of life, increased activities of daily living, and improved sports capabilities. Clinical outcomes of platelet-rich plasma injections for knee osteoarthritis may be related to the higher dose of platelets.