An 11-year old male castrated mixed breed dog (32kg) presented to the Cornell University Hospital for Animals’ Emergency Service for referral of a highly comminuted left diaphyseal closed femoral fracture of 1-day duration. On presentation, the patient was painful and non-ambulatory. Diagnostic procedures revealed a systemically stable patient. The principles of biological osteosynthesis were employed using a bridging bone plate combined with an intramedullary pin. The goal of this repair was to allow for early ambulation of the patient and to obtain normal long-term function. One day post-surgery, the patient was able to ambulate on all four limbs. Approximately 9-weeks out from surgery, the patient is doing clinically well with apparent return to previous function of the surgical limb.