PRP: Some efficacy, little significance
A 2014 double-blinded RCT analyzed the efficacy of PRP injection vs control injection for treating tennis elbow of at least 3 months’ duration.3 A total of 112 patients (mean age 48.4 years) received a 2- to 3-mL injection of PRP at a site blocked with bupivacaine; 113 patients (mean age 47.4 years) received an injection of 2 to 3 mL 0.5% bupivacaine only. Success was defined as a ≥25% improvement in pain score on a 100-point VAS.
At 24 weeks, the PRP group demonstrated a success rate of 83.9% compared with 68.3% in the control group (number needed to treat=6; P=.037). However, the difference between the mean VAS improvement of 38 points in the PRP group and the mean decrease of 36 points in the control group carries little clinical significance.