title: A modified periacetabular osteotomy with use of the transtrochanteric exposure.
abstract: BACKGROUND
  Periacetabular osteotomies are technically demanding surgical procedures. We developed a modified technique that uses a transtrochanteric approach. Our goal was to facilitate surgical exposure without compromising the results of surgery. The purpose of the present study was to review the early results in our initial group of patients who had this procedure.
  
  
  METHODS
  We retrospectively reviewed the results of a modified periacetabular osteotomy in thirty-eight consecutive patients (forty-six hips) at an average duration of follow-up of 4.2 years. The average age of the patients was thirty-one years (range, eighteen to fifty-eight years) at the time of surgery. We evaluated the results with use of serial radiographs and the Merle d'Aubigné and Postel hip-scoring system.
  
  
  RESULTS
  All osteotomies healed. Preoperatively, the average lateral center-edge angle was 3 degrees (range, -15 degrees to 12 degrees ), the anterior center-edge angle was 0 degrees (range, -20 degrees to 5 degrees ), the acetabular angle of Sharp was 57 degrees (range, 50 degrees to 68 degrees ), and the femoral head coverage was 53% (range, 40% to 66%). Postoperatively, the average lateral center-edge angle was 35 degrees (range, 23 degrees to 45 degrees ), the anterior center-edge angle was 32 degrees (range, 20 degrees to 55 degrees ), the acetabular angle of Sharp was 40 degrees (range, 37 degrees to 45 degrees ), and the femoral head coverage was 92% (range, 85% to 100%). The average amount of medialization of the femoral head was 6 mm. At the latest follow-up examination, improvement in the grade of osteoarthritis was noted in eight hips, while progression of osteoarthritis was seen in five hips. Functionally, the average Merle d'Aubigné and Postel hip score improved from 13.2 points preoperatively to 17.0 points postoperatively. No patient had a neurovascular complication.
  
  
  CONCLUSIONS
  Our early experience with a modified periacetabular osteotomy showed encouraging results in terms of the technical ease of the technique and the outcome in our patients.
authors.affiliation: Department of Orthopedics, Chang Gung Memorial Hospital, Kweishian, Taoyuan, Taiwan. 2634@adm.cgmh.com.tw
authors.forename: Pang-Hsin
authors.initials: PH
authors.lastname: Hsieh
authors.forename: Chun-Hsiung
authors.initials: CH
authors.lastname: Shih
authors.forename: Po-Cheng
authors.initials: PC
authors.lastname: Lee
authors.forename: Wen-E
authors.initials: WE
authors.lastname: Yang
authors.forename: Zhon Liau
authors.initials: ZL
authors.lastname: Lee
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D006618:Hip Dislocation, Congenital / Q000150:complications; D006801:Humans; D008297:Male; D008875:Middle Aged; D015207:Osteoarthritis, Hip / Q000209:etiology / Q000601:surgery*; D010027:Osteotomy / Q000379:methods*; D012189:Retrospective Studies; D016896:Treatment Outcome