title: Biomechanical evaluation of reconstruction plates with locking, nonlocking, and hybrid screws configurations in calcaneal fracture: a finite element model study.
abstract: Calcaneal fractures are the most common fractures of the tarsal bones. The stability of fixation is an important factor for successful reconstruction of calcaneal fractures. The purpose of this study was to analyze the biomechanical influence of plate fixation with different combinations of locking and nonlocking screws during early weight-bearing phase. A three-dimensional FE foot model was established using ANSYS software, which comprised bones, cartilages, plantar fascia, and soft tissue. Calcaneal plate was fixed with whole locking (WLS), whole nonlocking (WNS), and hybrid screw configurations for FE analysis. The WNS generated a 6.1° and 2.2° Bohler angle decrease compared with the intact model and WLS (WNS: 18.9; WLS: 21.1; intact: 25.0°). Some hybrid screw configurations (Bohler angle: 21.5° and 21.2°) generated stability similar to WLS. The FE results showed that the fragments at the posterior facet and the posterior tuberosity sustained more stress. This study recommends that the hybrid screw configuration with at least four locking screws, two at the posterior facet fragment and two at the posterior tuberosity fragment, is the optimal choice for the fixation of Sanders type IIB calcaneal fractures.
authors.affiliation: Department of Mechanical Engineering, National Chiao Tung University, Hsinchu, Taiwan.
authors.forename: Ching-Hsuan
authors.initials: CH
authors.lastname: Chen
authors.affiliation: Department of Mechanical Engineering, National Chiao Tung University, Hsinchu, Taiwan.
authors.forename: Chinghua
authors.initials: C
authors.lastname: Hung
authors.affiliation: College of Medicine and Engineering, Institute of Biomedical Engineering, National Taiwan University, Taipei, Taiwan.
authors.forename: Yu-Chun
authors.initials: YC
authors.lastname: Hsu
authors.affiliation: Department of Physical Therapy and Assistive Technology, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Chen-Sheng
authors.initials: CS
authors.lastname: Chen
authors.affiliation: Division of Orthopaedic Trauma, Department of Orthopaedics and Traumatology, Taipei Veterans General Hospital, Taipei, Taiwan. chiangcc@vghtpe.gov.tw.|Department of Surgery, School of Medicine, National Yang-Ming University, Taipei, Taiwan. chiangcc@vghtpe.gov.tw.
authors.forename: Chao-Ching
authors.initials: CC
authors.lastname: Chiang
mesh_terms: D001696:Biomechanical Phenomena / Q000502:physiology*; D001860:Bone Plates; D001863:Bone Screws; D002111:Calcaneus / Q000502:physiology*; D020342:Finite Element Analysis; D005528:Foot / Q000601:surgery; D005593:Fracture Fixation, Internal / Q000379:methods; D050723:Fractures, Bone / Q000601:surgery*; D006801:Humans; D016474:Weight-Bearing / Q000502:physiology
keywords: Biomechanics; Calcaneal fracture; Finite element analysis; Hybrid configuration; Locking plate; Nonlocking plate; Sanders IIB