Purpose To perform a systematic review evaluating indications, preparation methods, and outcomes of randomized controlled trials (RCTs) involving platelet‐rich plasma (PRP) injections for extra‐articular hip pathology. Methods A literature review was performed using the PubMed‐MEDLINE, Embase, and Cochrane databases. Only RCTs evaluating extra‐articular PRP hip injections were included. Study design, patient and disease characteristics, PRP processing methodology using the Platelet‐Activation‐White blood cell (PAW) classification, and patient‐reported outcomes were analyzed. Study quality was assessed by the revised Cochrane risk‐of‐bias tool for randomized trials (RoB2). Meta‐analyses were performed for studies evaluating the same pathology with comparable outcome metrics. Results Eleven RCTs (581 hips) were included with a focus on hamstring (five studies, 4 acute muscular injury; 208 patients, 1 chronic proximal tendinopathy; 17 patients), greater trochanteric pain syndrome or abductor tendinopathy (five studies; 263 patients), and piriformis (one study; 60 patients) pathology. PRP yielded superior outcomes compared to control groups for at least one time point in three RCTs (60%) on gluteal tendinopathy and two RCTs (50%) evaluating return to sport rate following acute hamstring injury. Meta‐analyses found high heterogeneity (I 2 = .92) in greater trochanteric pain syndrome (GTPS) studies with a significant treatment effect for the modified Harris Hip Score favoring PRP ( P = .005) compared to control groups ( P = .08). There was lower heterogeneity for hamstring studies (I 2 = .65) and a significant treatment effect favoring PRP with an 8‐day shorter return to sport ( P = .005). Conclusions All RCTs found improvements in pain and function following PRP injection with clinically relevant outcome thresholds and meta‐analyses favoring PRP when treating GTPS and hamstring pathology. While there is substantial heterogeneity in study design, PRP formulations, control groups, outcome metrics, and follow‐up time, all reviewed RCTs showed comparable or superior outcomes with PRP compared to controls. Level of Evidence Level I, systematic review of Level I randomized controlled trials.
Kuhns et al. (Thu,) studied this question.