Standardized Platelet Rich Plasma Injections for Osteoarthritis of the Knee

Objective Platelet-rich plasma (PRP) and adipose-derived stem cells (ADSC) injections are non-surgical treatments for knee osteoarthritis (OA). The purpose of this study is to assess the effectiveness of serial PRP with or without ADSC injections in the treatment of refractory OA of the knee.  Design Patients who failed to achieve pain relief with conventional non-surgical treatments, with Kellgren-Lawrence grade 3 or 4 knee OA, were recruited from a private outpatient clinic. Over 67 patients were elected to receive serial PRP injections and 22 patients were elected to receive an ADSC+PRP injection. These patients completed Western Ontario and McMaster Universities Arthritis Index (WOMAC) surveys prior to each treatment and at follow-up appointments. These surveys were retrospectively reviewed to assess changes in functional status and pain over time. Results Twenty-nine patients from the PRP group and eight patients in the ADSC+PRP group had adequate follow-up for inclusion in the analysis. The PRP group had an improvement in WOMAC scores by 34.30%, 60.2%, and 58.5% for patients reporting at 1-3, 4-6, and >6 months of follow-up. The ADSC+PRP group experienced an improvement of 51% at an average of 4.66 months of follow-up. Conclusions Serial PRP injections and a single ADSC+PRP injection yield improved and sustained functional outcome scores for patients with severe, refractory OA of the knee. Future studies should consider consistent orthobiologic preparation protocols to ensure reproducibility.