title: Mid-term results of metal-on-metal hip resurfacing for treatment of osteoarthritis secondary to developmental dysplasia of the hip: a minimum of 8-years of follow-up.
abstract: BACKGROUND
  Metal-on-metal resurfacing arthroplasty is an attractive alternative to conventional total hip arthroplasty in patients with osteoarthritis secondary to developmental dysplasia of the hip (DDH). The purpose of this study was to assess the mid-term clinical outcome and mid-term survivorship of Metal-on-metal resurfacing arthroplasty in patients suffering from osteoarthritis secondary to DDH.
  
  
  METHODS
  Between May 2003 and Dec. 2005, 15 operations using ASR™ and 19 using Corin were performed in 29 patients to treat advanced osteoarthritis secondary to DDHs. There were 6 males (20.7%) and 23 females (79.3%), with an average age of 47.2 years (range, 36-64 years). Clinical and radiographic results were observed. All patients were followed up at the 1st, 2nd, 3rd, 6th, and 12th months after surgery and annually thereafter.
  
  
  RESULTS
  The overall survival was 88.2% at a minimum follow-up of 8 years, but the survival was 91.2% after excluding the infections as the cause of component loosening and failure. The mean Harris hip score improved from 48.27±3.13 (range, 14-71) to 89.63±3.42 (range, 65-100) at latest follow-up. The flexion was from 75.14±8.05° to 107.21±9.34. Only 4 failed because of deep infection, femoral neck fracture, and aseptic loosening.
  
  
  CONCLUSIONS
  Metal-on-metal resurfacing arthroplasty showed perfect results at a minimum of 8-years of follow-up in our study, and may be a reasonable option for osteoarthritis secondary to developmental dysplasia of the hip (DDH).
authors.affiliation: Department of Orthopaedics, Changzhou Traditional Chinese Medical Hospital, Affiliated to Nanjing University of Traditional Chinese Medicine, Changzhou, China (mainland).
authors.forename: Yuxing
authors.initials: Y
authors.lastname: Qu
authors.affiliation: Department of Orthopaedics, Changzhou Traditional Chinese Medical Hospital, Affiliated to Nanjing University of Traditional Chinese Medicine, Changzhou, China (mainland).
authors.forename: Tao
authors.initials: T
authors.lastname: Jiang
authors.affiliation: Department of Orthopaedics, Changzhou Traditional Chinese Medical Hospital, Affiliated to Nanjing University of Traditional Chinese Medicine, Changzhou, China (mainland).
authors.forename: Hong
authors.initials: H
authors.lastname: Zhao
authors.affiliation: Department of Orthopaedics, Changzhou Traditional Chinese Medical Hospital, Affiliated to Nanjing University of Traditional Chinese Medicine, Changzhou, China (mainland).
authors.forename: Yi
authors.initials: Y
authors.lastname: Gao
authors.affiliation: Department of Orthopaedics, Changzhou Traditional Chinese Medical Hospital, Affiliated to Nanjing University of Traditional Chinese Medicine, Changzhou, China (mainland).
authors.forename: Chong
authors.initials: C
authors.lastname: Zheng
authors.affiliation: Department of Orthopaedics, Changzhou Traditional Chinese Medical Hospital, Affiliated to Nanjing University of Traditional Chinese Medicine, Changzhou, China (mainland).
authors.forename: Jianda
authors.initials: J
authors.lastname: Xu
mesh_terms: D000328:Adult; D019644:Arthroplasty, Replacement, Hip; D005260:Female; D005272:Femur Neck / Q000000981:diagnostic imaging / Q000601:surgery; D005500:Follow-Up Studies; D006618:Hip Dislocation, Congenital / Q000150:complications* / Q000000981:diagnostic imaging; D006622:Hip Prosthesis / Q000009:adverse effects; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D061825:Metal-on-Metal Joint Prostheses / Q000009:adverse effects; D008875:Middle Aged; D010003:Osteoarthritis / Q000000981:diagnostic imaging / Q000209:etiology* / Q000601:surgery*; D011182:Postoperative Care; D011183:Postoperative Complications / Q000209:etiology; D011300:Preoperative Care; D011859:Radiography; D013997:Time Factors; D016896:Treatment Outcome