Biomechanics of the goat three bundle anterior cruciate ligament.
The goat is a widely used animal model for basic research on the anterior cruciate ligament (ACL), but the biomechanical role of the different bundles [intermediate (IM), anteromedial (AM), posterolateral (PL)] of the ACL is unclear. Therefore, the aim of this study is to describe the biomechanical function of the different bundles and evaluate its use for a double bundle ACL reconstruction model. A CASPAR Stäubli RX90 robot with a six degree-of-freedom load cell was used for measurement of anterior tibial translation (ATT) (mm) and in situ forces (N) at 30 degrees (full extension), 60 degrees , 90 degrees as well as rotational testing at 30 degrees in 14 paired goat knees before and after each bundle was cut. When the AM-bundle was cut, the ATT increased significantly at 60 degrees and 90 degrees of flexion (p < 0.05). When the PL-bundle was cut, the ATT increased only at 30 degrees. However, most load was transferred through the big AM-bundle while the PL-bundle shared significant load only at 30 degrees, with only minimal contribution from the IM-bundle at all flexion degrees. The observed biomechanical results in this study are similar to the human ACL observed previously in the literature. Though anatomically discernible, the IM-bundle plays only an inferior role in ATT and might be neglected as a separate bundle during reconstruction. The goat ACL shows some differences to the human ACL, whereas the main functions of the ACL bundles are similar.
Tischer
T
T
Department of Orthopaedic Surgery, University of Pittsburgh, Pittsburgh, PA 15213, USA.
Ronga
M
M
Tsai
A
A
Ingham
S J M
SJ
Ekdahl
M
M
Smolinski
P
P
Fu
Freddie H
FH
D000818:Animals; D016118:Anterior Cruciate Ligament / Q000033:anatomy & histology / Q000502:physiology* / Q000601:surgery; D000070598:Anterior Cruciate Ligament Injuries; D001696:Biomechanical Phenomena; D006041:Goats; D007719:Knee Joint / Q000033:anatomy & histology / Q000502:physiology*; D023421:Models, Animal; D016059:Range of Motion, Articular / Q000502:physiology*; D012371:Robotics; D012399:Rotation