Platelet-Rich Plasma in Anterior Cruciate Ligament Reconstruction: An Updated Systematic Review and Meta-Analysis of Clinical and Radiological Outcomes

Background/Objectives: To evaluate the efficacy of platelet-rich plasma (PRP) as an adjunctive treatment in anterior cruciate ligament reconstruction (ACLR) and its impact on key clinical outcomes. Methods: A systematic search was conducted across five databases until 11 November 2024, including 33 randomized controlled trials (RCTs) that investigated PRP in ACLR. Outcomes analyzed included ligamentization (MRI hypointensity grades), pain VAS scores, functional scores (IKDC, Lysholm, Tegner), knee stability (KT-1000 arthrometer), and tunnel characteristics. Subgroup analyses were performed based on PRP application site, graft type, risk of bias, and follow-up duration. Results: PRP significantly enhanced ligamentization, particularly at 12 months, with marked reductions in MRI hypointensity grades. Patellar tendon grafts demonstrated the most substantial benefits. PRP also significantly reduced postoperative pain, with effects most pronounced in the early recovery period (1–9 months). However, the analgesic benefits diminished over time. Improvements in IKDC scores were observed only in studies with a high risk of bias, while Lysholm and Tegner scores showed no consistent differences between PRP and controls. Knee stability improved significantly with PRP, but this effect was limited to early follow-up periods (3 months). The heterogeneity in PRP preparation methods, application protocols, and patient populations limited the generalizability of the findings. Conclusions: PRP enhances ligamentization and provides short-term pain relief and stability benefits in ACLR. However, its impact on long-term functional recovery and other clinical outcomes remains limited and inconsistent. Standardization of PRP protocols and further high-quality research are necessary to refine its application and therapeutic potential.