title: Kinematics of active knee extension after tear of the anterior cruciate ligament.
abstract: Three-dimensional movements of the knees in 13 patients with unilateral old tears of ACLs were studied during extension. Roentgen stereophotogrammetric methods were used to measure tibial movements in the injured and the intact knees. Reduced internal rotation and adduction were recorded at the end of extension on both sides. The injured knees displayed increased anterior and distal displacements of the tibial intercondylar eminence. Abnormal tibial displacements in our patients indicate that the absence of the ACL is not completely compensated for during active extension past 30 degrees; close to the extended position, the tibial movements tend to normalize.
authors.affiliation: Department of Orthopedic Surgery, University Hospital, Umeå, Sweden.
authors.forename: H
authors.initials: H
authors.lastname: Jonsson
authors.forename: J
authors.initials: J
authors.lastname: Kärrholm
authors.forename: L G
authors.initials: LG
authors.lastname: Elmqvist
mesh_terms: D000293:Adolescent; D000328:Adult; D001696:Biomechanical Phenomena; D005260:Female; D006801:Humans; D007718:Knee Injuries / Q000503:physiopathology*; D007719:Knee Joint / Q000503:physiopathology*; D008023:Ligaments, Articular / Q000293:injuries / Q000503:physiopathology*; D008297:Male