Ninety patients with painful trapeziometacarpal osteoarthritis were randomized to receive a single intra-articular injection of platelet-rich plasma (n=45) or saline placebo (n=45). The primary outcome was change in pain on load (NRS 0–100) from baseline to 6 months. Secondary outcomes included change in pain on load at 3 months, pain at rest, Patient-Rated Wrist and Hand Evaluation (PRWHE) score, Disability of the Arm, Shoulder, and Hand (DASH) score, thumb range of motion, and pinch strength at 3 and 6 months. Overall, the results showed no significant difference in pain on load at 6 months between PRP and placebo, and no clinically relevant differences in secondary outcomes. The study concludes that a single PRP injection offers no short-term benefit for pain or function in trapeziometacarpal osteoarthritis.