The CT protocol, as described, was repeatable and reproducible for assessing the femoral and tibial alignment of dogs.

Medial-to-lateral drilling for transcondylar screw placement carries a higher risk of inadvertently penetrating the joint compared with lateral-to-medial drilling.

Objective: Describe the clinical findings and management of tibial fractures in cats in which plate osteosynthesis failed due to plate bending.Study Design: Multicentre, retrospective clinical study. Methods:Clinical histories and radiographs of 10 cats that suffered plate bending following plate or plate-rod fixation of tibial fractures were reviewed for signalment, fracture configuration and repair, post-operative and post-failure tibial alignment, ultimate treatment and outcome. Tibial alignment post-operatively and post-failure was compared using a paired T-test.Results: Mean age was 5.3 years and mean body weight was 5.0kg. All ten cats sustained complete fracture of the tibia with an accompanying fracture to the fibula. Tibial fractures were generally oblique (4/10) or spiral (4/10) with mild comminution (8/10) and located in the middle (3/10) or distal (6/10) third of the tibia. Initial fracture stabilisation was with a plate (6/10) or plate-rod combination (4/10) with the plate applied to the medial tibial surface. Non-reduced, lateral tibial wedge fragments were present in 5 fractures. Mean time to implant failure was 24 days. Mean tibial valgus angle increased from 12.9° to 30.9°

The accurate measurement of femoral varus angle is important in pre-surgical planning of distal femoral ostectomy. Radiography is normally used to obtain the femoral varus angle, and femoral rotational malpositioning will induce errors in the femoral varus angle measured. Bisection of the fabellae by the femoral cortices is commonly cited as a criterion by which to assess whether a radiographic projection is truly craniocaudal, yet this study has shown this not to be valid.

Case summaryTwo cats were presented with mandibular fractures following head trauma. Following a CT scan, both were diagnosed with fractures of the ramus. The CT scans were used to print three-dimensional (3D) models of the mandibular fractures, which were used to pre-contour stainless steel mini-plates. These were fixed to the models and the screw positions used to produce a stainless steel template. The template was used as a pattern during surgery to drill holes in the ramus so that the pre-contoured mini-plates could be fixed in the exact same position as they had been on the 3D model. The fractures healed in both cats achieving normal jaw function and occlusion.Relevance and novel informationConventional techniques used to treat caudal mandibular fractures in cats, such as maxillomandibular fixation and bignathic encircling and retaining device (BEARD), are associated with significant patient morbidity and postoperative complications. Internal rigid fixation is difficult because of small bone size, requirement for considerable plate contouring and difficulty in achieving accurate anatomical reduction of caudal mandibular fractures. These are the first reported cases of mini-plate fixation of caudal mandibular fractures in cats using 3D models, pre-contouring of bone plates and the use of a template to facilitate accurate plate positioning, which may provide an alternative technique suitable for fixing caudal mandibular fractures in cats.