Abstract
OBJECTIVE: To evaluate the clinical efficacy of sequential and single injection of platelet-rich plasma (PRP) in treatment of early/mid-stage knee osteoarthritis (KOA). METHODS: Ninety-four patients who were diagnosed of early/mid-stage KOA from 2022 to 2024 were included in this study, involving 39 case undergoing sequential intra-articular PRP injection (sequential PRP group) and 55 case undergoing single intra-articular PRP injection (single PRP group). Outcomes including serum interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) levels, synovial fluid matrix metalloproteinase-3 (MMP-3) and tissue inhibitor of metalloproteinases-1 (TIMP-1) levels, visual analog scale (VAS) score, Western Ontario and McMaster Universities Arthritis Index (WOMAC) score, Lysholm score and complications were all recorded and compared. RESULTS: At 6-month post-treatment, not only serum IL-1β, IL-6, and TNF-α, but also synovial fluid MMP-3 and TIMP-1, were significantly improved compared with those pre-treatment in each group. Compared with single PRP group, however, the sequential PRP group showed lower serum IL-1β, IL-6, TNF-α, synovial fluid MMP-3 and higher synovial fluid TIMP-1 at 6-month post-treatment. Both the two groups achieved significant improvements in VAS score, WOMAC score and Lysholm score at 1, 3, and 6 months post-treatment. Although no significant differences were found in VAS score, WOMAC score and Lysholm score between single PRP group and sequential PRP group at 1 and 3 months post-treatment, sequential PRP group had a lower VAS score and WOMAC score, and a higher Lysholm score at 6 months post-treatment. No significant difference was found in complications rate between the two groups and all cases were cured after active treatment. CONCLUSIONS: Both sequential and single injection of PRP can achieve satisfactory clinical efficacy in the treatment of early/mid-stage KOA, but sequential intra-articular PRP injection has the advantages of sustained long-term efficacy in relieving pain and improving knee joint function.