Does leucocyte concentration have a role in the outcome of PRP therapy for lateral epicondylitis -A randomized controlled trial

Background: Of late the leucocyte concentration in the platelet-rich plasma (PRP) therapy for lateral epicondylitis has gained importance. We aimed to evaluate the effects of leucocyte concentration in the outcomes of the PRP used for lateral epicondylitis. Materials and Methods: This is a double-blinded randomized controlled trial conducted on patients having lateral epicondylitis comparing the pain relief and functional effects of leucocyte-poor PRP (LP-PRP) and leucocyte-rich PRP (LR-PRP) at one, three, six, and twelve months post-injection using the Visual Analog Scale (VAS) for pain and Mayo Elbow Performance Score (MEPS) for function. Results: A total of 85 patients were randomized into LP-PRP (n=42) and LR-PRP (n=43) with a mean age of 49.67 (SD=11.9) and M:F = 1.34. The pre-treatment VAS between the LP-PRP and LR-PRP groups were 8.83�0.7 and 9.12�0.63 respectively while the pre-treatment MEPS were 44.81�8.6 and 45.45�5.43respectively. We noted significant improvement in the pain and functional scores in both the groups at all observed time frames compared to their pre-treatment measures. However, we did not find any significant difference in the MEPS between the groups nor the difference in the VAS found between the groups at 1year follow-up was more than the minimal clinically important difference (MCID) for the scale utilized. No significant difference in the complication rate was noted between either of the groups.Conclusion: PRP injections are a safe and effective treatment method in the management of patients with lateral epicondylitis irrespective of the concentration of the leucocytes present in them. We have established that the concentration of leucocytes did not play a role in altering the course of the treatment outcome.