title: [Prevention of lateral cortex fractures in open wedge high tibial osteotomies : The anteroposterior drill hole approach].
abstract: BACKGROUND
  In osteotomies with larger correction angles, the capacity for elastic deformation is frequently exceeded, resulting in plastic deformation and fracture of the opposite cortex, which may lead to subsequent loss of correction. An anteroposterior drill hole at the apex of the horizontal osteotomy (= hinge) is supposed to increase the capacity of the bony hinge for elastic deformation and ideally to prevent fractures of the opposite cortex.
  
  
  METHODS
  A high tibial osteotomy (HTO) using standard surgical technique was performed in 20 each of Synbones, Sawbones, and human cadaver tibial specimens. In 10 specimens per group, an additional anteroposterior hinge drilling was performed at the apex of the horizontal osteotomy. All fractures of the opposite cortex were photographically and radiographically documented. All fractures were classified according to fracture types 1-3 of the Takeuchi classification.
  
  
  RESULTS
  Regardless of the study group, all tibial bones with an additional hinge drilling achieved larger correction angles during the spreading of the wedge until a fracture of the opposite cortex occurred. The average correction angle of all specimens without the drill hole was 2.7°, which increased to 4.8° with the hinge drill (increase by 77.8%). In correction angles exceeding 5°, all specimen showed a hinge fracture regardless of the presence or absence of a hinge drill.
  
  
  CONCLUSIONS
  The hinge-protecting effect is restricted to small correction angles, i. e., to unload cartilage repair regions in the absence of severe malalignment. For the treatment of varus gonarthrosis, there is no fracture-protecting effect from a hinge drill.
authors.affiliation: Orthopädische Klinik des Centre Hospitalier de Luxembourg, Akademisches Lehrkrankenhaus der Universitätskliniken des Saarlandes, 78, rue d'Eich, 1460, Luxembourg, Luxemburg.|Sports Medicine Research Laboratory, Luxembourg Institute of Health, Luxembourg, Centre Médical de la Fondation Norbert Metz, 76 rue d'Eich, 1460, Luxembourg, Luxemburg.
authors.forename: G
authors.initials: G
authors.lastname: Reyle
authors.affiliation: Orthopädische Universitätsklinik des Saarlandes, Kirrbergerstr., Gebäude 37, 66421, Homburg/Saar, Deutschland.
authors.forename: O
authors.initials: O
authors.lastname: Lorbach
authors.affiliation: Faculty of Science, Technology and Communication, University of Luxembourg, 6, rue R. Coudenhove-Kalergi, 1359, Luxembourg, Luxemburg.
authors.forename: A
authors.initials: A
authors.lastname: Diffo Kaze
authors.affiliation: Orthopädische Klinik des Centre Hospitalier de Luxembourg, Akademisches Lehrkrankenhaus der Universitätskliniken des Saarlandes, 78, rue d'Eich, 1460, Luxembourg, Luxemburg.|Sports Medicine Research Laboratory, Luxembourg Institute of Health, Luxembourg, Centre Médical de la Fondation Norbert Metz, 76 rue d'Eich, 1460, Luxembourg, Luxemburg.
authors.forename: A
authors.initials: A
authors.lastname: Hoffmann
authors.affiliation: Orthopädische Klinik des Centre Hospitalier de Luxembourg, Akademisches Lehrkrankenhaus der Universitätskliniken des Saarlandes, 78, rue d'Eich, 1460, Luxembourg, Luxemburg. dietrichpape@yahoo.de.|Sports Medicine Research Laboratory, Luxembourg Institute of Health, Luxembourg, Centre Médical de la Fondation Norbert Metz, 76 rue d'Eich, 1460, Luxembourg, Luxemburg. dietrichpape@yahoo.de.|Cartilage Net of the Greater Region, 66421, Homburg/Saar, Deutschland. dietrichpape@yahoo.de.
authors.forename: D
authors.initials: D
authors.lastname: Pape
mesh_terms: D000071538:Cortical Bone / Q000000981:diagnostic imaging / Q000293:injuries*; D006801:Humans; D007431:Intraoperative Complications / Q000000981:diagnostic imaging / Q000517:prevention & control*; D007718:Knee Injuries / Q000000981:diagnostic imaging / Q000517:prevention & control*; D007719:Knee Joint / Q000000981:diagnostic imaging / Q000601:surgery*; D010027:Osteotomy / Q000379:methods*; D012307:Risk Factors; D013977:Tibia / Q000000981:diagnostic imaging / Q000293:injuries / Q000601:surgery*; D013978:Tibial Fractures / Q000000981:diagnostic imaging / Q000517:prevention & control*
keywords: High tibial osteotomy; Hinge drill; Lateral cortex fracture; Stress-relief hole; Tibial head