title: Reducing the rate of early primary hip dislocation by combining a change in surgical technique and an increase in femoral head diameter to 36 mm.
abstract: BACKGROUND
  We report how changes to our total hip arthroplasty (THA) surgical practise lead to a decrease in early hip dislocation rates.
  
  
  METHODS
  Group B consisted of 421 consecutive primary THA operations performed via a posterior approach. The operative technique included a meticulous repair of the posterior capsule, alignment of the acetabular cup with the transverse acetabular ligament (TAL) and a 36-mm-diameter femoral head. We compared the dislocation rates and cost implications of this technique to a historical control Group A consisting of 389 patients. The control group had their THA performed with no repair of the capsule, no identification of the TAL and all received a 28-mm-diameter head. Our primary outcome is the rate of early hip dislocation and we hypothesised that we can reduce the rate of early hip dislocation with this new regime.
  
  
  RESULTS
  In Group B there were no early dislocations (within 6 months) and two (0.5 %) dislocations within 18 months; minimum follow-up time was 18 months with a range of (18-96 months). This compared to a 1.8 % early dislocation rate and a 2.6 % rate at 18 months in Group A; minimum follow-up time was 60 months with a range of (60-112 months). These results were statistically significant (p = 0.006).
  
  
  CONCLUSIONS
  We suggest that when primary hip arthroplasty is performed through a posterior approach, a low early dislocation rate can be achieved using the described methods.
authors.affiliation: Worcestershire Royal Hospital, Worcester, UK. kevinho@btinternet.com
authors.forename: Ki Wai Kevin
authors.initials: KW
authors.lastname: Ho
authors.forename: George S
authors.initials: GS
authors.lastname: Whitwell
authors.forename: Steve K
authors.initials: SK
authors.lastname: Young
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019644:Arthroplasty, Replacement, Hip / Q000191:economics / Q000295:instrumentation / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D017048:Health Care Costs; D006617:Hip Dislocation / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control*; D006622:Hip Prosthesis / Q000191:economics; D006801:Humans; D008297:Male; D011183:Postoperative Complications / Q000453:epidemiology / Q000517:prevention & control*; D012189:Retrospective Studies; D016896:Treatment Outcome; D006113:United Kingdom