title: Eighty percent of patients with surgical hip dislocation for femoroacetabular impingement have a good clinical result without osteoarthritis progression at 10 years.
abstract: BACKGROUND
  We previously reported the 5-year followup of hips with femoroacetabular impingement (FAI) that underwent surgical hip dislocation with trimming of the head-neck junction and/or acetabulum including reattachment of the labrum. The goal of this study was to report a concise followup of these patients at a minimum 10 years.
  
  
  OBJECTIVE
  We asked if these patients had (1) improved hip pain and function; we then determined (2) the 10-year survival rate and (3) calculated factors predicting failure.
  
  
  METHODS
  Between July 2001 and March 2003, we performed surgical hip dislocation and femoral neck osteoplasty and/or acetabular rim trimming with labral reattachment in 75 patients (97 hips). Of those, 72 patients (93 hips [96%]) were available for followup at a minimum of 10 years (mean, 11 years; range, 10-13 years). We used the anterior impingement test to assess pain and the Merle d'Aubigné-Postel score to assess function. Survivorship calculation was performed using the method of Kaplan and Meier and any of the following factors as a definition of failure: conversion to total hip arthroplasty (THA), radiographic evidence of worsening osteoarthritis (OA), or a Merle d'Aubigné-Postel score less than 15. Predictive factors for any of these failures were calculated using the Cox regression analysis.
  
  
  RESULTS
  At 10-year followup, the prevalence of a positive impingement test decreased from preoperative 95% to 38% (p < 0.001) and the Merle d'Aubigné-Postel score increased from preoperative 15.3 ± 1.4 (range, 9-17) to 16.9 ± 1.3 (12-18; p < 0.001). Survivorship of these procedures for any of the defined failures was 80% (95% confidence interval, 72%-88%). The strongest predictors of failure were age > 40 years (hazard ratio with 95% confidence interval, 5.9 [4.8-7.1], p = 0.002), body mass index > 30 kg/m(2) (5.5 [3.9-7.2], p = 0.041), a lateral center-edge angle < 22° or > 32° (5.4 [4.2-6.6], p = 0.006), and a posterior acetabular coverage < 34% (4.8 [3.7-5.6], p = 0.006).
  
  
  CONCLUSIONS
  At 10-year followup, 80% of patients with FAI treated with surgical hip dislocation, osteoplasty, and labral reattachment had not progressed to THA, developed worsening OA, or had a Merle d'Aubigné-Postel score of less than 15. Radiographic predictors for failure were related to over- and undertreatment of acetabular rim trimming.
authors.affiliation: Department of Orthopaedic Surgery, Inselspital, University of Bern, Freiburgstrasse, 3010, Bern, Switzerland, simon.steppacher@insel.ch.
authors.forename: Simon D
authors.initials: SD
authors.lastname: Steppacher
authors.forename: Helen
authors.initials: H
authors.lastname: Anwander
authors.forename: Corinne A
authors.initials: CA
authors.lastname: Zurmühle
authors.forename: Moritz
authors.initials: M
authors.lastname: Tannast
authors.forename: Klaus A
authors.initials: KA
authors.lastname: Siebenrock
mesh_terms: D000293:Adolescent; D000328:Adult; D060826:Cementoplasty; D018450:Disease Progression; D005260:Female; D057925:Femoracetabular Impingement / Q000150:complications* / Q000601:surgery*; D005500:Follow-Up Studies; D006621:Hip Joint / Q000601:surgery*; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D019637:Orthopedic Procedures / Q000379:methods*; D015207:Osteoarthritis, Hip / Q000209:etiology*; D016016:Proportional Hazards Models; D016896:Treatment Outcome; D055815:Young Adult