Objective: To biomechanically evaluate the efficacy of the lateral tripod 3-pin (3LTP) technique as an alternative to crosspinning (XP) for Kirschner wire internal fixation of distal femoral physeal fractures in small-breed canines.
Methods: For this experimental biomechanical study (from February through October 2025), 30 polycarbonate 3-D-printed bone models simulating a Salter-Harris type I (SH-I) fracture were allocated equally (n = 10/group) to 3 fixation groups: the XP group, lateral double-pinning (2LP) group, and 3LTP group, all stabilized with 1.0-mm Kirschner wires. The maximum failure load (Newtons) was recorded as the primary outcome following an axial loading compression test on a universal testing machine until implant failure. Data were statistically analyzed.
Results: A total of 30 models were included in the final analysis (n = 10/group). The mean maximum failure loads were determined to be 385.60 N (95% CI, 367.5 to 403.7) for XP, 330.70 N (95% CI, 311.4 to 350.0) for 2LP, and 445.10 N (95% CI, 412.4 to 477.8) for 3LTP. The failure mode for all groups was implant bending.
Conclusions: The 3LTP demonstrated superior biomechanical resistance to axial compression compared to XP and 2LP for canine distal femoral SH-I fractures.
Clinical relevance: The utilization of the 3LTP technique offers a biomechanically superior and minimally invasive fixation alternative to XP for repairing canine distal femoral SH-I fractures.
