title: Surgical dislocation of the hip versus arthroscopic treatment of femoroacetabular impingement: a prospective matched-pair study with average 2-year follow-up.
abstract: OBJECTIVE
  The purpose of this study was to prospectively compare outcomes of patients receiving surgical hip dislocation and those undergoing arthroscopic treatment for femoroacetabular impingement (FAI), using a matched-pair analysis.
  
  
  METHODS
  Between January 2008 and August 2011, patients aged 30 years or younger with a diagnosis of FAI treated with surgical dislocation or arthroscopy were included. Patients were excluded with Tönnis grade 2 or greater, dysplasia, Legg-Calve-Perthes disease, and previous hip surgery. Patients treated with surgical dislocation were pair-matched to patients treated arthroscopically in a 1:2 ratio. Patient-reported outcomes were prospectively obtained in all patients preoperatively and postoperatively at 3 months, at 1 year, at 2 years, and at latest follow-up. Alpha angles were measured preoperatively and postoperatively for both groups. Revision surgery and complications were recorded for each group.
  
  
  RESULTS
  Ten patients were included in the surgical dislocation group, and 20 pair-matched patients were included in the arthroscopic group. We obtained 100% follow-up at a mean of 24.8 months in the open group and 25.5 months in the arthroscopic group. Preoperative scores were similar between the 2 groups; significant improvements were made postoperatively for both groups. When we compared the 2 groups, the change in Hip Outcome Score-Sport-Specific Subscale (42.8 v 23.5, P = .047) and 2-year Non-Arthritic Hip Score (94.2 v 85.7, P = .01) were significantly higher in the arthroscopic group. Both groups showed a significant decrease in the alpha angle postoperatively (P = .775).
  
  
  CONCLUSIONS
  Favorable results were shown with both approaches, with significant improvement in all patient-reported outcome measures and high patient satisfaction ratings. However, arthroscopic treatment of FAI showed greater improvement in the Hip Outcome Score-Sport-Specific Subscale and a higher absolute Non-Arthritic Hip Score at an average 2-year follow-up.
  
  
  METHODS
  Level II, prospective matched-pair comparative study.
authors.affiliation: Hinsdale Orthopaedics, Hinsdale, IL, USA. DrDomb@americanhipinstitute.org
authors.forename: Benjamin G
authors.initials: BG
authors.lastname: Domb
authors.forename: Christine E
authors.initials: CE
authors.lastname: Stake
authors.forename: Itamar B
authors.initials: IB
authors.lastname: Botser
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Jackson
mesh_terms: D000328:Adult; D001182:Arthroscopy / Q000379:methods*; D020878:Device Removal; D005260:Female; D057925:Femoracetabular Impingement / Q000601:surgery*; D005269:Femur / Q000601:surgery*; D005500:Follow-Up Studies; D006617:Hip Dislocation; D006621:Hip Joint; D006801:Humans; D008297:Male; D016555:Matched-Pair Analysis; D017060:Patient Satisfaction; D011446:Prospective Studies; D012086:Reoperation; D013997:Time Factors; D016896:Treatment Outcome; D055815:Young Adult