A Retrospective Study of Clinical and Radiographic Outcomes and Exploratory Analysis of Implant Failure in Dogs ≤ 5 kg Treated with Titanium Locking Mini-Plates for Radial and Ulnar Fractures

Radial and ulnar fractures in toy-breed dogs are associated with a high risk of complications due to limited bone stock and soft tissue coverage. The aim of this retrospective study was to evaluate the postoperative clinical and radiographic outcomes in dogs undergoing radial and ulnar fracture stabilization with a titanium locking mini-plate system. Medical records and radiographs of toy-breed dogs weighing ≤5 kg treated between 2020 and 2025 were reviewed. Twenty-six dogs met the inclusion criteria. Radiographic union after primary fixation was observed in 92.9% of fractures. Implant failure occurred in 7.1% of cases and was successfully addressed with revision surgery, after which fracture healing was achieved. At final follow-up, limb function was graded as excellent in all dogs, including those requiring revision surgery. A shorter distal fragment length was significantly associated with implant failure, whereas implant length and proximal fragment length showed no significant association. These findings indicate that titanium locking mini-plates were associated with favorable clinical and radiographic outcomes. Distal fragment dimensions may influence the risk of implant failure and should be considered during surgical planning. However, the small number of implant failure events limits the robustness of statistical inferences, and the absence of a control group prevents direct comparison with alternative fixation techniques.