Background/Purpose : We think that leukocyte concentration in PRP can affect local inflammatory response. In this study, we aimed to compare effects of leukocyte-rich and leukocyte-poor PRP on pain, functionality and post-injection local inflammatory reactions and adverse effects in patients with lateral epicondylitis.  

Methods : Overall, 90 patients with lateral epicondylitis-related pain (VAS score≥5) over >3 months were included to the study and randomly assigned into 3 groups. Normal saline (1.5 cc) was injected to the group 1 while a single dose of LP-PRP (1.5 cc) and LR-PRP (1.5 cc) were injected to groups 2 and 3, respectively. Same exercise program was prescribed to all three groups. The patients were assessed with VAS, Patient-Rated Tennis Elbow Evaluation (PRTEE), grip and pinch strength, extensor tendon thickness and cortical derangement at baseline and on weeks 4 and 8 after therapy. All patients were questioned regarding paracetamol use and adverse effects after therapy.

Results: The mean age was 47.63±9.05 years in  the control group while 45.03±8.57 years in LP-PRP and  46.49±8.73 years in LR-PRP group. The groups were comparable regarding age.  No significant differences were detected between groups regarding, VAS, PRTEE, , grip and pinch strength measurements, extensor tendon thickness and cortical derangement (p>0.05). No significant difference was detected in paracetamol use and post-injection reactions among groups. \s Figure 1: Patient-based PRTTE scores in groups

Conclusion: In our study, PRP was found to have no superiority to control groups in patients with lateral epicondylitis. Leukocyte concentration in PRP was also found to have no association to improvement in pain and function or adverse effects.