title: Effect of mini-fragment fixation on the stabilization of medial malleolus fractures.
abstract: BACKGROUND
  Oblique fractures of the medial malleolus can arise from the application of axial force at various anatomic positions of the ankle, including supination-external rotation, pronation-external rotation, or pronation abduction. Although a variety of techniques exist to provide fixation of horizontal medial malleolus fractures, the optimal technique and pattern for internal fixation remains unclear. The aim of this study was to evaluate the mechanical properties of four different fixation methods for fractures of the medial malleolus.
  
  
  METHODS
  Identical oblique osteotomies were created in synthetic distal tibiae using a jig. The specimens were divided into four fixation groups: contoured 2.0 mm mini-fragment T-plate, figure-of-eight tension band wire, construct two parallel 4.0 mm cancellous screws, and two divergent 4.0 mm cancellous screws. The specimens were tested using offset axial tension at 10 mm/min until 2 mm of joint line displacement.
  
  
  RESULTS
  The average stiffness in tension and force at 2 mm of joint line displacement of the plate construct was significantly greater than any of the other constructs (p < 0.05), whereas the average stiffness in tension of the other three groups were not significantly different from each other (p > 0.05).
  
  
  CONCLUSIONS
  Using a contoured 2.0 mm mini-fragment T-plate as the method of fixation resulted in an at least 25% stiffer construct during tension and required at least 24% more force for 2 mm of joint line displacement when compared with more traditional methods of fixation in an osteotomy model of an oblique medial malleolus fracture.
authors.affiliation: Department of Orthopedic Surgery, 4860 Y St, University of California, Davis, Sacramento, CA 95817, USA.
authors.forename: Derek F
authors.initials: DF
authors.lastname: Amanatullah
authors.forename: Erik
authors.initials: E
authors.lastname: McDonald
authors.forename: Adam
authors.initials: A
authors.lastname: Shellito
authors.forename: Shain
authors.initials: S
authors.lastname: Lafazan
authors.forename: Alejandro
authors.initials: A
authors.lastname: Cortes
authors.forename: Shane
authors.initials: S
authors.lastname: Curtiss
authors.forename: Philip R
authors.initials: PR
authors.lastname: Wolinsky
mesh_terms: D001696:Biomechanical Phenomena; D001860:Bone Plates; D001863:Bone Screws; D001864:Bone Wires; D005592:Fracture Fixation / Q000379:methods*; D005593:Fracture Fixation, Internal / Q000379:methods; D006801:Humans; D013977:Tibia / Q000473:pathology / Q000601:surgery; D013978:Tibial Fractures / Q000473:pathology / Q000601:surgery*; D016896:Treatment Outcome