The effect of tibial tuberosity advancement and meniscal release on kinematics of the cranial cruciate ligament-deficient stifle during early, middle, and late stance

Objectives: To evaluate the effect of tibial tuberosity advancement (TTA) and meniscal release on cranial-caudal and axial rotational displacement during early, middle and late stance phases in the canine cranial cruciate ligament- (CCL) deficient stifle. Study design: In vitro biomechanical study. Methods: Eighteen pelvic limbs were evaluated for the effects of TTA on cranial-caudal displacement and axial rotation under a load equivalent to 30% bodyweight, and under the following treatment conditions: normal (intact CCL), CCL deficient, TTA-treated (CCL deficient + TTA), and meniscal release (TTA treated + meniscal release). The limbs were evaluated in the early, middle, and late stance phases using electromagnetic tracking sensors to determine cranial tibial displacement and tibial rotation relative to the femur. Results: Transection of the CCL resulted in significant cranial tibial displacement during early, middle, and late stance (p < 0.0001) and significant internal rotation during early (p = 0.049) and middle stance (p = 0.0006). Performance of TTA successfully eliminated cranial tibial displacement in early, middle, and late stance (p <0.0001); however, the TTA was unsuccessful in normalizing axial rotation in middle stance (p = 0.030). Meniscal release had no effect on cranial-caudal or rotational displacement when performed in conjunction with the TTA. Clinical significance: Tibial tuberosity advancement effectively eliminates cranial tibial displacement during early, middle and late stance; however, TTA failed to provide rotational stability in mid-stance.