title: Three-dimensional computerized preoperative planning of total hip arthroplasty with high-riding dislocation developmental dysplasia of the hip.
abstract: OBJECTIVE
  To assess whether computed tomography (CT)-based 3-dimensional (3D) computerized pre-operative planning is accurate and reliable in patients with high-riding dislocation developmental dysplasia of the hip (DDH) undergoing total hip arthroplasty (THA).
  
  
  METHODS
  Between September 2009 and February 2011, a prospective study with an inbuilt means of comparing predictive techniques in 20 patients (20 hips) with high-riding dislocation DDH was undertaken. All patients had pre- and post-operative CT scans, data from which were transferred digitally to Mimics software. 3D pre-operative planning to predict the acetabular component size, hip rotation center position and acetabular component coverage was performed using Mimics software. The results and post-operative course were compared with those of the traditional acetate templating technique.
  
  
  RESULTS
  Using 3D computerized planning, 14/20 components (70%) were predicted exactly and 6/20 (30%) within one size, whereas with the conventional acetate templating technique, 5/20 components (25%) were predicted exactly, 9/20 (45%) within one size and 6/20 (30%) within two or more sizes. There was a strong correlation between the 3D computerized planned acetabular component size, hip rotation center distance, acetabular component host coverage and that found postoperatively. Five patients were considered to need structural bone graft on the basis of 3D computerized planning; this was highly coincident with the intraoperative findings in all five cases.
  
  
  CONCLUSIONS
  CT-based 3D computerized pre-operative planning using Mimics software is an accurate and reliable technique for patients with high-riding dislocation DDH undergoing THA.
authors.affiliation: Department of Orthopaedic Surgery, West China Hospital, West China Medical School, Sichuan University, Chengdu, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Zeng
authors.forename: Ou-jie
authors.initials: OJ
authors.lastname: Lai
authors.forename: Bin
authors.initials: B
authors.lastname: Shen
authors.forename: Jing
authors.initials: J
authors.lastname: Yang
authors.forename: Zong-ke
authors.initials: ZK
authors.lastname: Zhou
authors.forename: Peng-de
authors.initials: PD
authors.lastname: Kang
authors.forename: Fu-xing
authors.initials: FX
authors.lastname: Pei
authors.forename: Xuan
authors.initials: X
authors.lastname: Zhou
mesh_terms: D000077:Acetabulum / Q000000981:diagnostic imaging / Q000473:pathology; D000328:Adult; D019644:Arthroplasty, Replacement, Hip / Q000379:methods*; D017076:Computer-Aided Design; D005260:Female; D006618:Hip Dislocation, Congenital / Q000000981:diagnostic imaging / Q000601:surgery*; D006622:Hip Prosthesis; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D008297:Male; D008875:Middle Aged; D011300:Preoperative Care / Q000379:methods*; D011446:Prospective Studies; D011474:Prosthesis Design; D012984:Software; D025321:Surgery, Computer-Assisted / Q000379:methods; D014057:Tomography, X-Ray Computed / Q000379:methods
keywords: Developmental dysplasia of the hip; Hip arthroplasty; Mimics software