Background Lateral epicondylitis (LE) is a common musculoskeletal disorder for which an effective treatment strategy still remains absent.
Objectives To examine whether one injection with Platelet-rich plasma (PRP) is more effective than saline and corticosteroid (CS) in reducing pain in adults with LE.
Methods A block randomized, double-blind, placebo-controlled trial with primary outcome assessed at 3 months, and with a 12 months follow-up, conducted between January 2009, and June 2011. Patients who did not achieve a satisfying treatment response (assessment made by patient and doctor) at 3 month had the option to discontinue the study and receive other treatment. In total, 60 patients with chronic LE were randomized (1:1:1) to receive either a blinded injection of PRP, saline or CS. The primary outcome was change in pain compared to baseline using the Patient Rated Tennis Elbow Evaluation (PRTEE) questionnaire at 3 months. Secondary endpoints were all assessed at 1 month, plus ultrasonographic changes in tendon thickness and color doppler activity at 3 months.
Results The 60 enrolled patients in the intention to treat population had an average PRTEE pain score at baseline of 26.8 (SD 7.6). All randomized patients completed the study. At endpoint 3 months from baseline pain reduction was observed in all three groups, with no statistical significant difference between the groups. CS vs. saline -3.76 (95% CI -9.94 to 2.42), PRP vs. saline -2.64 (95% CI -8.80 to 3.52) and CS vs. PRP -1.12 (95% CI -7.23 to 4.99). However, at one month CS reduced pain more efficiently than both saline and PRP. The mean difference at one month between CS and saline was -8.11 (95% CI -14.29 to -1.93), between CS and PRP -9.27 (95% CI -15.38 to -3.16). CS was more efficient than PRP and saline in reducing both color doppler activity and tendon thickness at three months. Only 16 of 60 patients completed the entire 12 months follow-up. The huge attrition rate was due to lack of treatment efficacy.
Conclusions This RCT showed no superiority of either PRP or CS compared to saline in pain reduction in LE at primary endpoint. However, anticipating immediate relief, CS had a short term pain reducing effect at one month in contrast to the other therapies. At 6 and 12 months the attrition rates in all treatment arms were too high for any meaningful conclusions to be made.
Disclosure of Interest None Declared