Safe zones for external skeletal fixator in the dog distal femur

External fixators can be successfully used to treat femoral fractures. Due to the large muscle mass surrounding the femur, there can be higher morbidities; muscle movement often leads to pin tract irritation. Pins should only be inserted from the lateral direction to avoid interference with the movement and damage to neurovascular structures.

A 1 cm incision is performed from proximal to distal through the skin at the desired location of pin placement.

Blunt or sharp dissection through the muscle should be performed along the same line to reach the bone.

The fixator pins must be placed in the center of the bone. Two hypodermic needles or palpation can be used to locate the bone during closed application of the fixator. Due to the large muscle mass in the femur, it might be easier to do this after the skin incision through the muscle has been made.

Note: In the distal femur ensure that the transfixation pin does not penetrate the articular surface.

The skin incision is left open to heal by secondary intention.