title: Platelet-Rich Plasma Injections With Needle Tenotomy for Gluteus Medius Tendinopathy: A Registry Study With Prospective Follow-up.
abstract: BACKGROUND
  Gluteal tendinopathy is a prevalent condition that can be associated with significant pain and disability. To date, no studies have prospectively assessed the efficacy of intratendinous platelet-rich plasma (PRP) injections as a minimally invasive treatment for gluteus medius tendinopathy.
  
  
  OBJECTIVE
  To prospectively assess the efficacy of intratendinous PRP injections as treatment for chronic recalcitrant gluteus medius tendinopathy.
  
  
  METHODS
  Case series; Level of evidence, 4.
  
  
  METHODS
  During the study period between July 2011 and November 2015, data were collected from the Hospital for Special Surgery Center for Hip Preservation Outcomes Registry on participants who underwent ultrasound-guided intratendinous PRP injections for recalcitrant gluteus medius tendinosis and/or partial tears of the tendon associated with moderate to severe lateral hip pain for longer than 3 months. All participants were assessed pre- and postinjection with 4 outcome measures: modified Harris Hip Score (mHHS), Hip Outcome Score-Activities of Daily Living subscale (HOS-ADL), Hip Outcome Score-Sport-Specific subscale (HOS-Sport), and the International Hip Outcome Tool-33 (iHOT-33). Demographic data, including age, sex, height, weight, body mass index, and smoking status, were also collected.
  
  
  RESULTS
  A total of 21 patients were included in the study, with a mean follow-up of 19.7 months (range, 12.1-32.3 months). The mean improvements from preinjection to postinjection follow-up were 56.73 to 74.17 for mHHS, 68.93 to 84.14 for HOS-ADL, 45.54 to 66.72 for HOS-Sport, and 34.06 to 66.33 for iHOT-33. All mean outcome measure improvements were clinically and statistically significant (P< .001). Length of follow-up was positively correlated with improvements in HOS-ADL (P= .021) and HOS-Sport (P= .004) scores. No adverse events were observed during or after the procedure.
  
  
  CONCLUSIONS
  In this registry study with prospective follow-up, we found ultrasound-guided intratendinous PRP injections to be a safe and effective treatment option for chronic recalcitrant gluteus medius tendinopathy due to moderate to severe tendinosis and/or partial tendon tears. Well-powered randomized controlled studies are warranted to confirm our findings and further define the ideal candidates for this treatment.
authors.affiliation: Hospital for Special Surgery, New York, New York, USA.
authors.forename: James J
authors.initials: JJ
authors.lastname: Lee
authors.affiliation: Hospital for Special Surgery, New York, New York, USA.
authors.forename: Julian R
authors.initials: JR
authors.lastname: Harrison
authors.affiliation: Hospital for Special Surgery, New York, New York, USA.
authors.forename: Kwadwo
authors.initials: K
authors.lastname: Boachie-Adjei
authors.affiliation: Hospital for Special Surgery, New York, New York, USA.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Vargas
authors.affiliation: Hospital for Special Surgery, New York, New York, USA.
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Moley
keywords: gluteus medius tendon; platelet-rich plasma; tendinopathy; tenotomy