title: Effect of acetabular reinforcement ring with hook for acetabular dysplasia clarified by three-dimensional finite element analysis.
abstract: The objective of this study was to biomechanically determine the effect of the severity of acetabular dysplasia, number and positions of screws and type of bone graft material used on the initial fixation strength of the acetabular reinforcement ring with hook (Ganz ring) using the finite element method. Relative micromotion increased as the severity of acetabular dysplasia increased and tended to decrease as the number of screws increased, but varied according to screw placement position. Increased strength of the bone graft material led to decreased relative micromotion. Biomechanically, the Ganz ring can be placed securely using 3 screws in patients with Crowe 1 dysplasia. However, in patients with Crowe 2 or higher dysplasia, it is necessary to spread at least 4 screws across an area of good host bone.
authors.affiliation: Department of Orthopaedic Surgery, Faculty of Medicine, University of Miyazaki, Kiyotake, Miyazaki, Japan.
authors.forename: Xin
authors.initials: X
authors.lastname: Zhao
authors.forename: Etsuo
authors.initials: E
authors.lastname: Chosa
authors.forename: Go
authors.initials: G
authors.lastname: Yamako
authors.forename: Shinji
authors.initials: S
authors.lastname: Watanabe
authors.forename: Gang
authors.initials: G
authors.lastname: Deng
authors.forename: Koji
authors.initials: K
authors.lastname: Totoribe
mesh_terms: D000077:Acetabulum / Q000601:surgery*; D019644:Arthroplasty, Replacement, Hip / Q000295:instrumentation / Q000379:methods*; D001696:Biomechanical Phenomena; D001863:Bone Screws; D016025:Bone Transplantation; D020342:Finite Element Analysis; D006618:Hip Dislocation, Congenital / Q000503:physiopathology / Q000601:surgery*; D006622:Hip Prosthesis; D006801:Humans; D021621:Imaging, Three-Dimensional; D008954:Models, Biological
keywords: Ganz ring; acetabular dysplasia; total hip arthroplasty