title: Complications following conversion of a hip hemiarthroplasty to a total hip arthroplasty.
abstract: OBJECTIVE
  Conversion of hip hemiarthroplasty to total hip arthroplasty (CTHA) is a complication-prone procedure with high dislocation rates and early component loosening. The purpose of this study was to evaluate the complications of CTHA performed using contemporary implants.
  
  
  METHODS
  Forty-six patients who had CTHA were retrospectively matched to a control group of 46 patients who had a first-time THA revision. The mean follow-up was 47 (range 6-149) and 23 (range 6-139) months for CTHA and control groups, respectively. Radiographs taken at the last follow-up visit were evaluated for signs of loosening or other modes of failure. Clinical outcome was evaluated with the Harris Hip Score (HHS).
  
  
  RESULTS
  Complications occurred in five patients (10.9 %) in the CTHA group, and all required repeat revision. Two patients (4.3 %) were revised due to recurrent dislocation. The other re-revisions were done for acetabular or femoral component loosening and deep infection. In the control group, complications occurred in six patients (13.0 %), and three (6.5 %) were revised with a constrained liner due to recurrent dislocations.
  
  
  CONCLUSIONS
  Dislocation rates and re-revision for CTHA were not significantly different than those of first-time THA revision when using contemporary revision implants.
authors.affiliation: Mount Sinai Hospital, Division of Orthopaedic Surgery, University of Toronto, 600 University Avenue, Toronto, Ontario, M5G 1X5, Canada.
authors.forename: Simcha G
authors.initials: SG
authors.lastname: Fichman
authors.affiliation: Mount Sinai Hospital, Division of Orthopaedic Surgery, University of Toronto, 600 University Avenue, Toronto, Ontario, M5G 1X5, Canada. tatu.makinen@hus.fi.
authors.forename: Tatu J
authors.initials: TJ
authors.lastname: Mäkinen
authors.affiliation: Mount Sinai Hospital, Division of Orthopaedic Surgery, University of Toronto, 600 University Avenue, Toronto, Ontario, M5G 1X5, Canada.
authors.forename: Alex
authors.initials: A
authors.lastname: Vincent
authors.affiliation: Mount Sinai Hospital, Division of Orthopaedic Surgery, University of Toronto, 600 University Avenue, Toronto, Ontario, M5G 1X5, Canada.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Lozano
authors.affiliation: Mount Sinai Hospital, Division of Orthopaedic Surgery, University of Toronto, 600 University Avenue, Toronto, Ontario, M5G 1X5, Canada.
authors.forename: Oleg
authors.initials: O
authors.lastname: Safir
authors.affiliation: Mount Sinai Hospital, Division of Orthopaedic Surgery, University of Toronto, 600 University Avenue, Toronto, Ontario, M5G 1X5, Canada.
authors.forename: Paul R T
authors.initials: PR
authors.lastname: Kuzyk
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects*; D005260:Female; D062785:Hemiarthroplasty / Q000009:adverse effects*; D006617:Hip Dislocation / Q000209:etiology* / Q000601:surgery; D006621:Hip Joint / Q000601:surgery; D006622:Hip Prosthesis / Q000009:adverse effects; D006801:Humans; D007592:Joint Diseases / Q000601:surgery; D008297:Male; D008875:Middle Aged; D011475:Prosthesis Failure; D016459:Prosthesis-Related Infections / Q000209:etiology* / Q000601:surgery; D012086:Reoperation; D012189:Retrospective Studies; D055815:Young Adult
keywords: Conversion; Dislocation; Hemiarthroplasty; Revision; Total hip arthroplasty