Design and validation of a knee-loading rig to perform clinical injury assessments in vitro.

摘要

The pivot shift test is used by clinicians to identify ACL damage in the knee. A Quasi-Static Knee Loading Rig (QKR) was designed and built to perform clinical injury assessments. Using the QKR, researchers applied forces and moments to the tibia, compressive loads through the knee, and quadriceps muscle forces. The QKR was used to evaluate the effects of valgus moment, internal moment, and quadriceps muscle force on the pivot shift test in porcine knees. The pivot shift was also administered with the moments applied by hand. The magnitude of the internal and valgus moments did not significantly affect the pivot shift score, but the internal moment did qualitatively change the knee's behavior. The pivot shifts performed by hand consistently scored highest because the researchers optimized the loading to enhance the pivot shift. The study demonstrated that the QKR consistently identified pathologic changes in the knee's behavior from a ruptured ACL.