Tibial plateau levelling osteotomy in 69 small breed dogs using conically coupled 1.9/2.5 mm locking plates A clinical and radiographic retrospective assessment

Objective: To report clinical experiences with the tibial plateau levelling osteotomy (TPLO) procedure in small breed dogs with cranial cruciate ligament (CCL) disease using specific, conically coupled, 1.9/2.5 mm locking plates and evaluating short-term complications and outcome. Methods: Medical records of small breed dogs (<15 kg) that underwent TPLO using 1.9/2.5 mm locking plates were reviewed retrospectively. The preoperative, postoperative and six to eight weeks postoperative tibial plateau angle (TPA) measurements were determined from the radiographic images. Lameness evaluation was assessed subjectively preoperatively and six to eight weeks postoperatively. Results: Sixty-nine small breed dogs (n = 79 stifles) were included in the study. Mean (+/- SD) preoperative TPA was 29.0 +/- 3.4 degrees, postoperative TPA was 5.8 +/- 2.5 degrees, and six to eight weeks postoperative TPA was 7.3 +/- 4.1 degrees. Sixteen complications occurred in 12 out of 79 TPLO procedures: three were intraoperative (intra-articular screw placement) and 13 were postoperative complications, of which nine were identified as minor complications not requiring surgical reintervention, and four as major complications requiring additional surgical intervention, including tibial tuberosity fracture (n = 1), osteomyelitis (n = 1), screw failure (n = 1), and plate breakage (n = 1). Lameness scores by clinical assessment reduced from a median value of 3/4 preoperatively to 1/4 at six to eight weeks postoperatively. Clinical significance: 1.9/2.5 mm locking plates appear to be a valid choice of implant for the stabilization of unilateral TPLO in small breed dogs.