title: Sectioning the anterolateral ligament did not increase tibiofemoral translation or rotation in an ACL-deficient cadaveric model.
abstract: OBJECTIVE
  The anterolateral ligament (ALL) has been proposed as a possible extra-articular stabiliser of the knee. Injury to the ALL may result in residual instability following surgical reconstruction of a ruptured anterior cruciate ligament (ACL). Few studies have evaluated the biomechanical role of the ALL. The purpose of this study was to investigate whether sectioning the ALL would have an influence on tibiofemoral translation or rotation during the anterior drawer, Lachman, pivot shift, external rotation, and internal rotation tests in an ACL-deficient knee.
  
  
  METHODS
  Only whole-body specimens having an ALL were included in this study. Lachman, anterior drawer, external rotation, and internal rotation tests were performed manually. Pivot shift test was done using a mechanised pivot shifter. The amount of tibiofemoral translation and rotation was recorded by a navigation system. Each specimen was tested in its native state, after sectioning the ACL, and after combined sectioning of the ACL and the ALL.
  
  
  RESULTS
  In six out of 14 cadaveric knees, an ALL could be identified. The ACL-deficient knee had significantly more tibiofemoral translation and rotation compared to the native knee (P < 0.05). However, no changes in the magnitudes of translation or rotation were seen after subsequent sectioning of the ALL compared to the ACL-deficient knee (P > 0.05).
  
  
  CONCLUSIONS
  Adding an ALL lesion in an ACL-deficient knee did not increase tibiofemoral instability in this cadaveric model. It remains unclear whether injury to the ALL would result in substantial knee instability in the setting of ACL injury in vivo. Further research is warranted to fully elucidate the role of the ALL during knee kinematics and to determine in which scenarios ALL repair would be warranted. Understanding the function of the ALL may improve the current treatment strategies for ACL ruptures.
authors.affiliation: Trauma Department, Hannover Medical School, Carl-Neuberg-Straße 1, 30625, Hannover, Germany.
authors.forename: Yousif Al
authors.initials: YA
authors.lastname: Saiegh
authors.affiliation: Trauma Department, Hannover Medical School, Carl-Neuberg-Straße 1, 30625, Hannover, Germany.
authors.forename: Eduardo M
authors.initials: EM
authors.lastname: Suero
authors.affiliation: Trauma Department, Hannover Medical School, Carl-Neuberg-Straße 1, 30625, Hannover, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Guenther
authors.affiliation: Trauma Department, Hannover Medical School, Carl-Neuberg-Straße 1, 30625, Hannover, Germany.
authors.forename: Nael
authors.initials: N
authors.lastname: Hawi
authors.affiliation: Trauma Department, Hannover Medical School, Carl-Neuberg-Straße 1, 30625, Hannover, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Decker
authors.affiliation: Trauma Department, Hannover Medical School, Carl-Neuberg-Straße 1, 30625, Hannover, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Krettek
authors.affiliation: Trauma Department, Hannover Medical School, Carl-Neuberg-Straße 1, 30625, Hannover, Germany.
authors.forename: Musa
authors.initials: M
authors.lastname: Citak
authors.affiliation: Trauma Department, Hannover Medical School, Carl-Neuberg-Straße 1, 30625, Hannover, Germany. omar.mohamed@mh-hannover.de.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Omar
mesh_terms: D000328:Adult; D000070598:Anterior Cruciate Ligament Injuries / Q000503:physiopathology*; D002102:Cadaver; D005260:Female; D006801:Humans; D007593:Joint Instability / Q000503:physiopathology*; D007719:Knee Joint / Q000502:physiology*; D008023:Ligaments, Articular / Q000601:surgery*; D008297:Male; D012399:Rotation
keywords: Anterior cruciate ligament; Anterolateral ligament; Biomechanics; Pivot shift test; Tibiofemoral rotation; Tibiofemoral translation