The effectiveness of platelet-rich plasma injections in gluteal tendinopathy - a randomised, double-blind controlled trial comparing a single platelet-rich plasma injection with a single corticosteroid injection.

Abstract

IMPORTANCE: Gluteus medius/minimus tendinopathy is a common cause of lateral hip pain or greater trochanteric pain syndrome. OBJECTIVE: There would be no difference in the modified Harris Hip score between a single Platelet-Rich-Plasma (PRP) injection compared to a corticosteroid injection (CSI) in the treatment of gluteal tendinopathy. DESIGN: Randomised Controlled Clinical Trial; Level of evidence 1, recruitment 29 May 2013 to May 2015, follow-up September 2016. Treating/assessing clinicians and subjects were blinded to treatment. PARTICIPANTS: 228 consecutive patients referred with gluteal tendinopathy were screened to enrol 80 participants. 148 excluded (refusal 48, previous surgery 39, sciatica 28, osteoarthritis 17, full thickness tears tendons 17, other 22). INTERVENTION: Subjects were randomised (1:1) to receive either a blinded glucocorticoid or platelet-rich plasma injection intra-tendinously under ultrasound guidance. MAIN OUTCOME MEASURE: A pain and functional assessment was performed using a Modified Harris Hip Score (MHHS) questionnaire at 0, 2, 6 and 12 weeks and patient acceptable symptomatic state (PASS) and minimally important clinical difference (MICD) at 12 weeks. RESULTS: Subjects had a mean age of 60, a ratio of female to male of 9:1 and mean length of symptoms >14 months. Pain and function measured by the mean MHHS showed no difference at 2 weeks CSI 66.95 (SD 15.14) vs PRP 65.23 (SD 11.60) or 6 week CSI 69.51 (SD 14.78) vs PRP 68.79 (SD 13.33). The mean MHHS was significantly improved at 12 weeks PRP 74.05 (SD 13.92) compared to the CSI group with a mean score of 67.13 (SD 16.04, p = 0.048). The PRP group achieved a PASS score of 74 at 12 weeks, reflecting clinical recovery. The proportion of subjects who achieved the MICD of more than 8 points at 12 weeks was 21/37 (56.7%) in the CSI group and 32/39 (82%) in the PRP group (p = 0.016). CONCLUSION: Patients with chronic gluteal tendinopathy >4 months, diagnosed with both clinical and radiological examinations, achieved greater clinical improvement at 12 weeks when treated with a single PRP injection than those treated with a single corticosteroid injection.