Comparative Outcomes of Platelet-Rich Plasma and Autologous Blood Injection in Patients with Chronic Lateral Epicondylitis

Background: Lateral epicondylitis is a common overuse tendinopathy, and regenerative therapies such as platelet-rich plasma (PRP) and autologous blood injection (ABI) are increasingly used as alternatives to corticosteroids. However, direct comparative data remain limited, particularly in low-resource settings. Objective: To compare the efficacy and safety of a single-dose PRP injection versus ABI in patients with chronic lateral epicondylitis over a 6-month follow-up period. Methods: This single-centre, randomized controlled trial enrolled 44 patients (22 per group) with chronic lateral epicondylitis unresponsive to conservative treatment. Participants received either a single aseptic injection of PRP or ABI. The primary outcome was pain reduction, assessed using the Visual Analog Scale (VAS). Secondary outcomes included functional improvement (PRTEE, DASH), patient satisfaction, adverse events, and non-responder rates. Assessments were performed at baseline, 6 weeks, 3 months, and 6 months. Results: Both treatment groups demonstrated significant improvements in pain and function over time (PRP: p < 0.001; ABI: p < 0.001). At 6 months, the PRP group achieved significantly lower VAS scores (1.6 ± 0.7 vs. 2.9 ± 0.8, p < 0.00001), superior PRTEE scores (21.4 ± 5.2 vs. 32.7 ± 6.8, p = 0.00067), and lower DASH scores (19.2 ± 4.7 vs. 30.8 ± 5.5, p < 0.000001). A greater proportion of PRP patients reported being “very satisfied” (54.5% vs. 27.3%), though this difference was not statistically significant (p = 0.316). Non-responder rates were lower with PRP (9.1% vs. 27.3%), and adverse events in both groups were mild and self-limiting. Conclusion: A single-dose PRP injection was more effective than ABI in reducing pain, improving function, and enhancing patient-reported outcomes in chronic lateral epicondylitis, with a favourable safety profile. These findings support PRP as a superior biologic treatment option and a potential first-line injectable therapy in clinical practice