80 patients with lateral epicondylitis were randomized to injection treatment with either platelet-rich plasma or corticosteroid (triamcinolone). Patients were assessed for outcome on a visual analog scale for pain, the Disabilities of the Arm, Shoulder and Hand score, the Mayo Elbow Performance score, and grip strength after 6 weeks and 3 months. Findings demonstrated significantly favourable results at 6 weeks in the CS injection group compared to the PRP group for all variables, while conversely at 3 months, the PRP injection group was significantly favourable to the CS injection group for all variables.