Effect of tibial insertion site for lateral suture stabilization on the kinematics of the cranial cruciate ligament deficient-stifle during early, middle and late stance: an in vitro study.

OBJECTIVE To evaluate the effect of two tibial attachment sites for lateral suture stabilization (LSS) on the three-dimensional femorotibial translational and rotational movements of the cranial cruciate ligament- deficient canine stifle during the early, middle and late stance phases. STUDY DESIGN In vitro biomechanical study: 32 hindlimbs from 16 canine cadavers. METHODS Limbs were mounted in a testing jig and an electromagnetic tracking system was used to determine the three-dimensional femorotibial translational and rotational movements under 33% of body weight load during early, middle and late stance in the following sequence: cranial cruciate ligament-intact, cranial cruciate ligament-deficient and LSS with the distal anchor through the tibial tuberosity (LSSTT) or through the cranial eminence of the extensor groove (LSSEG). The proximal anchor point was the lateral femorofabellar ligament. RESULTS Post-LSS stifle three-dimensional femorotibial translational and rotational movements were more comparable to normal than post-transection movements for both techniques. Both LSS techniques restored femorotibial movements in cranial cruciate ligament-deficient stifles to varying amounts but neither technique successfully restored normal three-dimensional femorotibial movements. The LSSEG improved femorotibial movements of the cranial cruciate ligament-deficient stifle in the medial-lateral direction and axial rotation but performed poorly in restoring femorotibial movements in the cranial-caudal direction as compared to the LSSTT. CLINICAL SIGNIFICANCE Both the LSSTT and LSSEG techniques failed to completely restore normal three-dimensional femorotibial translational and rotational movements in cranial cruciate ligament-deficient stifles in vitro.