Platelet-rich plasma (PRP) therapy for knee arthritis: a feasibility study in primary care

Background: Platelet-rich plasma (PRP) is a concentrate of autologous blood growth factors which has been shown to provide some symptomatic relief in early osteoarthritis (OA) of the knee. The objective of this study was to test the feasibility and efficacy potential of platelet rich plasma (PRP) in primary care. Methods: Feasibility study to assess safety of the intervention procedures and assess primary and secondary outcome measures. Consecutive patients presenting with symptomatic knee OA were recruited in a primary care setting in Ireland. All participants received three injections of PRP 4 weeks apart. The following self-reported clinical outcomes were evaluated before and after therapy (4 months): Pain and disability (ICOAP questionnaire); health utility (EUROQol); adverse events; patient satisfaction and goal-orientated outcomes. Results: Seventeen potential patients were identified of whom 14 were eligible to participate. Twelve consented and completed the intervention and all outcome measures. There were no losses to follow-up. One patient reported pain and stiffness for 2 days after the first injection but did complete the study. No growth was detected from nine consecutive samples sent for microbiology analysis. Changes in constant, intermittent and total pain scores were reported; pain fully resolved in two patients. In addition, health utility, patient satisfaction and goal-orientated outcomes also demonstrated improvement. Conclusions: Platelet-rich plasma therapy is a simple and minimally invasive intervention which is feasible to deliver in primary care to treat osteoarthritis of the knee joint. Well-designed randomised controlled trials are needed to measure outcomes, durability of effect and cost effectiveness.