Second look arthroscopic findings after tibial plateau leveling osteotomy.

OBJECTIVE: To describe the long-term (range, 2-69 months) arthroscopic appearance of intraarticular structures of the stifle after tibial plateau leveling osteotomy (TPLO). STUDY
DESIGN: Case series. ANIMALS: Dogs (n=63) that had repeat arthroscopic examination of the stifle after TPLO for treatment of a cranial cruciate ligament (CCL) deficient stifle.
METHODS: Medical records (2002-2008) of dogs that had repeat arthroscopic examination to evaluate intraarticular structures after previous TPLO for treatment of CCL injury. Regions of interest were the CCL, caudal cruciate ligament, articular cartilage, and menisci. Signalment, weight, and time to 2nd look arthroscopy were recorded. Radiographs were reviewed to measure pre- and postoperative tibial plateau angle, and craniocaudal limb alignment.
RESULTS: There were 17 partial CCL tears with early fiber tearing and 46 stifles with a complete CCL tear or incompetent partial CCL tear. Stifles with an early partial tear had normal to near normal appearance of intraarticular structures. Most dogs with a complete or incompetent partial CCL tear had axial or abaxial grades 3 or 4 articular cartilage abrasion of the medial or lateral femoral condyle.
CONCLUSION: Intraarticular structures appeared normal or near normal in dogs with early fiber tearing (caudolateral or craniomedial fibers). Most dogs that had a partial tear with an incompetent remaining CCL or a completely ruptured CCL had grades 3 or 4 articular cartilage abrasion. CLINICAL RELEVANCE: Early diagnosis of a CCL injury and treatment by TPLO may be protective against further CCL disruption lending stability to the joint and decreasing the incidence of meniscal injury and articular cartilage damage.