Efficacy of Autologous Platelet-Rich Plasma Injections for Grade 3 Symptomatic Degenerative Meniscal Lesions: A 1-Year Follow-up Prospective Study

Background: Platelet-rich plasma (PRP) injections have been proposed as a biologic option to provide symptomatic relief and delay surgery in patients with degenerative joint disease of osteoarthritis (OA). The efficacy of autologous PRP on symptomatic degenerative meniscal lesions (DMLs) has never been investigated. Hypothesis: We hypothesized that patients with symptomatic DMLs without OA undergoing autologous PRP injections experience a significant clinical improvement at 12 months. Study Design: Prospective case series. Level of Evidence: Level 4. Methods: A total of 69 patients with symptomatic DMLs without radiographic evidence of knee OA (Kellgren-Lawrence radiographic grading scale 0-1) received 4 autologous PRP injections once a week. Patients were prospectively evaluated before the injection and then at 1, 3, 6, and 12 months. Evaluation was based on Lysholm knee scoring scale (primary outcome), Western Ontario and McMaster Universities Arthritis Index (WOMAC), Tegner activity scale, and visual analogue scale scores. Results: Patients treated with PRP injections demonstrated an improving knee function and symptoms over the duration of the study. A significant improvement from baseline to 12 months was observed in all the outcome measures, and no patients experienced failure or required surgery during the follow-up. Patients younger than 50 years reported lower subjective level of pain and higher Tegner activity scale at baseline and had significantly better Lysholm knee scoring scale (P = 0.03) and WOMAC (P = 0.03) scores at 6 months, as well as better range of motion at 3, 6, and 12 months (P < 0.001). Thirty-three (47.8%) patients were very satisfied, 26 (37.7%) satisfied, 8 (11.6%) partially satisfied, and 2 (2.9 %) not satisfied, with 62 (89.8%) patients willing to repeat the same treatment. No patient was lost to follow-up and no patient experienced adverse reaction, infection, failure, recurrence or underwent further surgery. Conclusion: PRP injections provide short-term benefits in symptomatic DMLs. Although promising results were evident at 12 months, this is a preliminary study and no definitive recommendation can be made based, for example, on longer follow-up. Clinical Relevance: This research supports the use of autologous PRP injections for symptomatic DMLs.