title: A novel tool for objective assessment of femorotibial rotation: a cadaver study.
abstract: Traumatic rupture of the anterior cruciate ligament (ACL) of the knee is one of the most frequent orthopaedic sports' injuries. However, the best operative reconstruction technique is still the focus of current discussions among experts. While single-bundle reconstruction primarily addresses anterior-posterior instability, the anatomical double-bundle reconstruction aims to stabilise anterior-posterior as well as rotational instability. So far no definite evidence to favour the one or the other technique exists due to the lack of an objective method for quantifying rotational knee stability. In this context several authors have recently reported on devices for the analysis of femorotibial rotation. However, most of these tools are still in the developmental stage. Therefore, the aim of this study was (1) to develop a new instrument for assessing rotational knee stability independent from the surrounding soft tissue with an adequate method of analysis and (2) to establish the possible field of application of this device in a human cadaver study. The so-called torsiometer evaluated was designed to assess internal and external knee joint rotation objectively in different flexion angles. Measurements were performed implying internal and external rotation at 90°, 30° and 0° knee flexion with and without intact ACL, respectively. Each measurement revealed valid and reproducible values. The restraint in ACL-absent knees was clearly lower and the course of rotation explicitly higher than in knee joints with intact ACL.
authors.affiliation: Department of Traumatology, Klinikum Rechts der Isar, Technische Universitaet Muenchen, Ismaninger Strasse 22, 81675, Munich, Germany.
authors.forename: Philipp
authors.initials: P
authors.lastname: Ahrens
authors.forename: Chlodwig
authors.initials: C
authors.lastname: Kirchhoff
authors.forename: Florian
authors.initials: F
authors.lastname: Fischer
authors.forename: Petra
authors.initials: P
authors.lastname: Heinrich
authors.forename: Rüdiger von
authors.initials: Rv
authors.lastname: Eisenhart-Rothe
authors.forename: Stefan
authors.initials: S
authors.lastname: Hinterwimmer
authors.forename: Sonja
authors.initials: S
authors.lastname: Kirchhoff
authors.forename: Andreas B
authors.initials: AB
authors.lastname: Imhoff
authors.forename: Stefan G F
authors.initials: SG
authors.lastname: Lorenz
mesh_terms: D016118:Anterior Cruciate Ligament / Q000601:surgery; D000070598:Anterior Cruciate Ligament Injuries; D053587:Arthrometry, Articular / Q000295:instrumentation* / Q000379:methods; D001696:Biomechanical Phenomena; D002102:Cadaver; D004867:Equipment Design; D005269:Femur / Q000502:physiology*; D006801:Humans; D007593:Joint Instability / Q000517:prevention & control / Q000601:surgery; D007719:Knee Joint / Q000502:physiology*; D008875:Middle Aged; D016059:Range of Motion, Articular / Q000502:physiology; D012399:Rotation; D013977:Tibia / Q000502:physiology*; D014102:Torsion Abnormality / Q000175:diagnosis* / Q000503:physiopathology