33rd Annual Scientific Meeting proceedings

Introduction
Spherical tibial plateau leveling osteotomy (STPLO) has been described as treatment option for cranial cruciate ligament rupture (CCLR) with and without concomitant patellar luxation. The objective of this study was to compare the tibial axis after STPLO and standard tibial plateau leveling osteotomy (TPLO) for limbs without deformity.

Materials and Methods
Orthopedically healthy cadaveric hindlimbs of medium to large-breed dogs were collected. The left and right limbs of one individual were assigned to two different groups (Group-1: TPLO;  Group-2: STPLO). Surgery was performed by a single experienced surgeon. Mechanical tibial axis angles were measured on pre- and postoperative mediolateral and craniocaudal radiographs of the tibia. Medial proximal tibial angle (mMPTA), medial distal tibial angle (mMDTA), caudal proximal tibial angle (mCdPTA), cranial distal tibial angle (mCrDTA) and TPA were measured by one observer (author). Pre- and postoperative angles were compared within and between the two groups using a t-test (p<0.05).

Results
Eight limbs of 5 male and 3 female dogs (1 Labrador, 1 Golden Retriever and 6 mixed breed dogs) were included. Mean age was 9.25 ± 2.6 years. Mean preoperative angles did not differ between groups. Mean postoperative angles did not differ significantly between Group-1 (TPA: 7.84±2.60o; mMPTA: 91.6±3.8 o; mMDTA: 96.8±2.7 o, mCdPTA: 82.2±4.3 o; mCrDTA: 84±5.7 o) and Group-2 (TPA: 8.30 ± 3.96 o; mMPTA: 91.1±2.2 o; mMDTA: 96.1±1.9o; mCdPTA: 81.7±4.2 o; mCrDTA: 83±6 o).

Discussion/Conclusion
Spherical tibial plateau leveling osteotomy is able to adequately correct the TPA while maintaining the tibial axis.