The Use of a Hybrid External Skeletal Fixator Construct for the Management of Tibial Tuberosity Avulsion Fractures in Three Dogs

Three juvenile dogs presented for evaluation of a tibial tuberosity avulsion fracture. Interfragmentary wires were placed and articulated with a hybrid circular-linear external skeletal fixator construct. Minor wire and pin tract inflammation was observed at 2 weeks postoperatively when the fixators were removed. The position of the tuberosity had not changed and the tuberosity physes had not closed. At 4 to 6 weeks postoperatively, dogs 1 and 3 were fully weight bearing on the operated limb. Dog 2 had a mild lameness and radiographs revealed mild proximal displacement of the tibial tuberosity. Final follow-up was obtained at 52, 55, and 130 weeks. No abnormalities were noted on orthopaedic examination for dogs 1 and 3. Dog 2’s owner reported mild lameness after strenuous activity; a grade I/IV medial patellar luxation was appreciated on the operated limb. Radiographs revealed complete healing of the tibial tuberosity avulsion fracture with closure of the physes in all three dogs.

The hybrid construct allowed for successful stabilization of the tibial tuberosity with only mild associated complications. Fixator removal 2 weeks postoperatively allowed for sufficient fibrous union of the tibial tuberosity in two dogs, while minor proximal displacement of the tibial tuberosity occurred after frame removal in dog 2. Fixator removal allowed for continued growth through the apophysis in all three dogs. Clinical outcome was determined to be excellent in two dogs, with complete resolution of lameness, and good in one dog, with reported mild intermittent lameness.

Acknowledgment: There was no proprietary interest or funding provided for this project.