title: Metal-on-metal dysplasia cup total hip arthroplasty for hip osteoarthritis secondary to developmental dysplasia of the hip.
abstract: OBJECTIVE
  This study aims to evaluate the clinical and radiological results of metal-on-metal dysplasia cup total hip arthroplasty (THA) for hip osteoarthritis secondary to developmental dysplasia of the hip (DDH).
  
  
  METHODS
  Between May 2009 and October 2011, THA was performed on 27 hips (7 Crowe type II, 9 Crowe type III, 11 Crowe type IV) of 22 patients (2 males, 20 females; mean age 43 years; range 25 to 63 years) with hip osteoarthritis secondary to DDH. All patients were evaluated clinically and radiographically.
  
  
  RESULTS
  Average follow-up period was 34.2 months (range 24-53 months). While mean Harris hip score (HHS) was 43 (range 30 to 72 points) preoperatively, it was 92 (range 87 to 98 points) at final follow-up. Two patients developed sciatic nerve palsy postoperatively. Recurrent dislocation occurred in one patient one year after the operation. Mean cup inclination was 45.6° (range 42°-51°). Heterotopic ossification developed in eight patients. No patient's acetabular and femoral component migrated or subsided significantly. None of the implants was revised.
  
  
  CONCLUSIONS
  Early clinical and radiological results of metal-on-metal dysplasia cup THA in DDH are satisfactory.
authors.affiliation: Department of Orthopedics and Traumatology, Medical Faculty of Karadeniz Teknik University, 61000 Trabzon, Turkey. bakiemre61@yahoo.com.
authors.forename: Mehmet Emre
authors.initials: ME
authors.lastname: Baki
authors.forename: Alper
authors.initials: A
authors.lastname: Timurkaynak
authors.forename: Hafız
authors.initials: H
authors.lastname: Aydın
authors.forename: Celal
authors.initials: C
authors.lastname: Baki
mesh_terms: D000328:Adult; D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects / Q000295:instrumentation*; D005260:Female; D005500:Follow-Up Studies; D006618:Hip Dislocation, Congenital / Q000150:complications; D006621:Hip Joint / Q000000981:diagnostic imaging / Q000601:surgery; D006801:Humans; D008297:Male; D061825:Metal-on-Metal Joint Prostheses; D008875:Middle Aged; D009999:Ossification, Heterotopic / Q000209:etiology; D015207:Osteoarthritis, Hip / Q000209:etiology / Q000601:surgery*; D011859:Radiography; D016896:Treatment Outcome