Temporal changes in WOMAC scores following intra-articular platelet-rich plasma injection in knee osteoarthritis: a prospective cohort study

Background Knee osteoarthritis (OA) is a leading cause of disability, with limited regenerative treatment options. Platelet-rich plasma (PRP) has emerged as a promising biologic therapy. Objective To evaluate the clinical efficacy of intra-articular PRP injections in patients with knee OA using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score. Patients and methods A prospective observational study was conducted on 40 patients with Kellgren–Lawrence grade II–III knee OA. All patients received two intra-articular PRP injections at 2-week intervals. WOMAC scores were recorded at baseline and 6 months postinjection. Clinical parameters, including swelling, tenderness, warmth, and crepitus, were also assessed. Results The mean baseline WOMAC score was 40.31 ± 13.18, which significantly improved to 16.09 ± 4.22 at 6 months ( P <0.001). Significant improvements were observed in pain, stiffness, and physical function subscales. Tenderness showed significant clinical improvement ( P <0.001), while swelling, warmth, and crepitus did not reach statistical significance. Conclusion Intra-articular PRP injection significantly improves WOMAC scores and clinical symptoms in patients with moderate knee OA. PRP is a safe and effective nonsurgical option for symptom relief.