Platelet-Rich Plasma Injection for Painful Trapeziometacarpal Osteoarthritis: A Double-Blind, Randomized, Placebo-Controlled Trial.

Background: Intra-articular injection of platelet-rich plasma (PRP) for osteoarthritis (OA) has increased in popularity recently. Evidence of the effect in hand OA is weak. The aim of this study was to evaluate if PRP injection decreases pain and disability due to trapeziometacarpal OA compared with placebo. Methods: Double-blind trial of 90 patients with painful trapeziometacarpal OA that were randomized to a single intra-articular injection of either PRP (n = 45) or placebo (saline injection) (n = 45) in the trapeziometacarpal joint. The primary outcome was change in pain on load (Numerical Rating Scale (NRS) 0 to 100) from baseline to 6 months after injection. Secondary outcomes were change in pain on load after 3 months; change in pain at rest; Patient-Rated Wrist and Hand Evaluation; Disability of the Arm, Hand, and Shoulder score; range of motion; key pinch; and 3-finger pinch strength, after 3 and 6 months. Results: One PRP patient was lost to follow-up. The mean age was 63 years, and 58 participants were women. Before intervention, median pain on load was 65 (interquartile range [IQR] 45-80) in the PRP group and 60 (IQR 40-80) in the placebo group. At 6 months, median pain change was -10 (95% CI -20 to 0) in the PRP group and 0 (95% CI 0-10) in the placebo group (absolute difference -10 (-20 to 0), p = 0.22). No clinically relevant differences were found in secondary outcomes. Conclusion: A single PRP injection has no short-term effect on pain on load compared with placebo for trapeziometacarpal osteoarthritis. Level of evidence: Level 1. See Instructions for Authors for a complete description of levels of evidence.