title: Rotational Acetabular Osteotomy for Osteoarthritis with Acetabular Dysplasia: Conversion Rate to Total Hip Arthroplasty within Twenty Years and Osteoarthritis Progression After a Minimum of Twenty Years.
abstract: BACKGROUND
  We investigated the rate of conversion to total hip arthroplasty by twenty years and radiographic findings at a minimum of twenty years after rotational acetabular osteotomy.
  
  
  METHODS
  Between June 1986 and August 1991, we performed 172 rotational acetabular osteotomies in 168 patients with acetabular dysplasia. Of those, ninety-three hips (ninety-one patients), including twenty-three hips with pre-osteoarthritis, twenty-nine with initial osteoarthritis, and forty-one with advanced osteoarthritis, had clinical and radiographic findings available. The mean age of the patients was 32.4 years (range, twelve to forty-nine years). The duration of follow-up was a mean of twenty-three years (range, twenty to twenty-seven years) for seventy-six hips, excluding hips that underwent conversion to total hip arthroplasty.
  
  
  RESULTS
  Conversion to total hip arthroplasty by twenty years after surgery was performed in one hip (4%) with pre-osteoarthritis, two hips (7%) with initial osteoarthritis, and fourteen hips (34%) with advanced osteoarthritis. The hips with advanced osteoarthritis had a significantly higher rate of conversion to total hip arthroplasty than hips in the other stages did (p = 0.0005). At the latest follow-up or at conversion to total hip arthroplasty, the disease stage had not progressed in seventeen hips (74%) with pre-osteoarthritis, nineteen (66%) with initial osteoarthritis, and twenty-six (63%) with advanced osteoarthritis.
  
  
  CONCLUSIONS
  The progression of osteoarthritis after rotational acetabular osteotomy was not detected for at least twenty years in most hips with either pre-osteoarthritis or initial osteoarthritis in this cohort. Rotational acetabular osteotomy may delay conversion to total hip arthroplasty in advanced osteoarthritis.
  
  
  METHODS
  Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.
authors.affiliation: Department of Orthopaedic Surgery, Kanazawa Medical University, 1-1 Daigaku, Uchinada-machi, Kahoku-gun, Ishikawa, 920-0293 Japan. E-mail address for A. Kaneuji: kaneuji@kanazawa-med.ac.jp.
authors.forename: Ayumi
authors.initials: A
authors.lastname: Kaneuji
authors.affiliation: Department of Orthopaedic Surgery, Kanazawa Medical University, 1-1 Daigaku, Uchinada-machi, Kahoku-gun, Ishikawa, 920-0293 Japan. E-mail address for A. Kaneuji: kaneuji@kanazawa-med.ac.jp.
authors.forename: Tanzo
authors.initials: T
authors.lastname: Sugimori
authors.affiliation: Department of Orthopaedic Surgery, Kanazawa Medical University, 1-1 Daigaku, Uchinada-machi, Kahoku-gun, Ishikawa, 920-0293 Japan. E-mail address for A. Kaneuji: kaneuji@kanazawa-med.ac.jp.
authors.forename: Toru
authors.initials: T
authors.lastname: Ichiseki
authors.affiliation: Department of Orthopaedic Surgery, Kanazawa Medical University, 1-1 Daigaku, Uchinada-machi, Kahoku-gun, Ishikawa, 920-0293 Japan. E-mail address for A. Kaneuji: kaneuji@kanazawa-med.ac.jp.
authors.forename: Kiyokazu
authors.initials: K
authors.lastname: Fukui
authors.affiliation: Department of Orthopaedic Surgery, Kanazawa Medical University, 1-1 Daigaku, Uchinada-machi, Kahoku-gun, Ishikawa, 920-0293 Japan. E-mail address for A. Kaneuji: kaneuji@kanazawa-med.ac.jp.
authors.forename: Eiji
authors.initials: E
authors.lastname: Takahashi
authors.affiliation: Department of Orthopaedic Surgery, Kanazawa Medical University, 1-1 Daigaku, Uchinada-machi, Kahoku-gun, Ishikawa, 920-0293 Japan. E-mail address for A. Kaneuji: kaneuji@kanazawa-med.ac.jp.
authors.forename: Tadami
authors.initials: T
authors.lastname: Matsumoto
mesh_terms: D000077:Acetabulum / Q000473:pathology / Q000601:surgery*; D000293:Adolescent; D000328:Adult; D000359:Aftercare; D019644:Arthroplasty, Replacement, Hip; D001848:Bone Diseases, Developmental / Q000601:surgery*; D002648:Child; D018450:Disease Progression; D005500:Follow-Up Studies; D006801:Humans; D008875:Middle Aged; D015207:Osteoarthritis, Hip / Q000150:complications / Q000601:surgery*; D010027:Osteotomy / Q000379:methods*; D013997:Time Factors