title: Preoperative planning and postoperative evaluation of total hip arthroplasty that takes combined anteversion.
abstract: The purpose of this study was to investigate whether postoperative combined anteversion (CA) can be kept within the safe zone while using cementless total hip arthroplasty (THA) using the operative technique which prepares the socket first for developmental dysplasia of the hip (DDH), by estimating the anteversion of the metaphyseal fit stem using preoperative three-dimensional (3D) computerized planning and by adjusting the anteversion of the socket using a navigation system that considers CA. Our subjects were 65 patients (65 hips) that had undergone cementless THA for DDH that could be observed for 1 year or more. Clinical assessments were made using the Japanese Orthopaedic Association's (JOA) hip score. For a radiological evaluation, we investigated 3D-planned stem versions, postoperative stem versions, preoperative and postoperative CA, and the relationship between CA and dislocation tendencies with temporary intraoperative reductions. JOA hip scores improved from 52.3 ± 11.4 points to 88.9 ± 8.6 points. CT evaluations revealed that 3D-planned stem versions were strongly correlated with postoperative stem versions (r = 0.80; p < 0.01). Preoperative CA was 50.5° ± 7.2°, and postoperative CA was 41.3° ± 8.6°. Postoperative CA was kept within the safe zone in 61 hips. No intraoperative dislocation tendencies were observed in any hips. By estimating the anteversion of the cementless metaphyseal fit stem using 3D planning preoperatively and adjusting the angle of anteversion of the socket using a navigation system that considers CA intraoperatively, postoperative CA can very frequently be kept within the safe zone, even with cementless THA using the operative technique which prepares the socket first for DDH.
authors.affiliation: Department of Bone and Joint Surgery, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime, 791-0295, Japan. hiroimai@m.ehime-u.ac.jp.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Imai
authors.affiliation: Department of Bone and Joint Surgery, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime, 791-0295, Japan.
authors.forename: Joji
authors.initials: J
authors.lastname: Miyawaki
authors.affiliation: Department of Bone and Joint Surgery, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime, 791-0295, Japan.
authors.forename: Tomomi
authors.initials: T
authors.lastname: Kamada
authors.affiliation: Department of Bone and Joint Surgery, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime, 791-0295, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Takeba
authors.affiliation: Department of Bone and Joint Surgery, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime, 791-0295, Japan.
authors.forename: Naohiko
authors.initials: N
authors.lastname: Mashima
authors.affiliation: Department of Bone and Joint Surgery, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime, 791-0295, Japan.
authors.forename: Hiromasa
authors.initials: H
authors.lastname: Miura
mesh_terms: D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods; D005260:Female; D006618:Hip Dislocation, Congenital / Q000175:diagnosis / Q000453:epidemiology / Q000601:surgery; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D019637:Orthopedic Procedures / Q000379:methods*; D010043:Outcome and Process Assessment, Health Care; D010347:Patient Care Planning; D011182:Postoperative Care / Q000379:methods
keywords: Combined anteversion; Developmental dysplasia of the hip; Preoperative 3D-planning; The metaphyseal fit stem; The operative technique which prepares the socket first; Total hip arthroplasty