Evaluation of a transcondylar toggle system for stabilization of the cranial cruciate deficient stifle in small dogs and cats.

OBJECTIVE: To evaluate use of a transcondylar toggle system (TCTS) for stabilization of the cranial cruciate ligament (CrCL) deficient stifle in small dogs and cats. STUDY DESIGN: Prospective clinical study. ANIMALS: Small dogs (<7 kg; n=14) and cats (2) with CrCL-associated lameness of <3 months duration and a tibial plateau angle <32 degrees. METHODS: Affected animals had an extracapsular CrCL repair using the TCTS. Lameness score, muscle atrophy, osteoarthritis (OA) score, and range of motion (ROM) were evaluated preoperatively, and at 6 weeks and 7-10 months postoperatively. RESULTS: Operative time was 75 +/- 16 minutes. Fifty-six percent required >1 bone tunnel attempts. One dog required revision at 2 weeks because of suture loosening. All stifles were stable at 6 weeks postoperatively. Fifteen animals were available for follow-up (7-10 months). Lameness improved significantly at 6 weeks (P<.0001), whereas muscle atrophy was worse at 6 weeks (P=.008) but improved at 7-10 months (P<.0001). OA scores were unchanged at 6 weeks (P=.08) but were significantly worse at 7-10 months (P<.0001). ROM remained unchanged at 6 weeks (P=1) and 7-10 months (P=.6). CONCLUSIONS: The medially placed toggle provides a reliable short-term proximal anchor for the extracapsular suture with outcomes similar to other extracapsular techniques. The aiming device and drill bit are not recommended in their current form. CLINICAL RELEVANCE: The TCTS appears to be a well-tolerated technique for proximal suture anchoring in extracapsular CrCL repair in small dogs and cats where instrumentation and anatomic constraints preclude other techniques.