Small Animals Fracture Repair

Head and Neck

A. Fracture of the Mandible Symphysis

Fractures of mandible symphysis are common in both dog and cat. Fracture may be only slightly displaced with moderate instability. Surgical technique includes wiring, pinning and wiring, lag screw.

Figure 1 : Radiograph of a fractured mandibular symphysis is a cat.

Figure 2: Radiograph of a Pekingese dog with resorption of the rostral ends of the mandibles.

Figure 3: Slightly displaced mandibular fracture.

Figure 4: Ventral view of a fractures mandibular symphysis fastened with a single wire suture, as would be done in a cat.

Figure 5: Ventrodorsal view of a fracture of the mandiblular symphysis secured with a lag screw. Note that the hole nearest the screw head is enlarged so that the screw threads do not engage.

B. Body of the Mandible

Fractures of the mandibular body are very common in dog. Accurate alignment and firm immobilization are required. General anaesthesia is required because it is essential to close the mouth to check proper occlusion. Surgical technique include wiring, pin and wire, external fixation (KIE apparatus), plating as shown in Figures 6, 7, 8, 9.

Figure 6: Lateral view of a fracture of the mandible repaired with wire. Two holes have been drilled in the rostral fragment and two in the caudal fragment. (B) The correct pattern for wire insertion.

Figure 7: Ventrodorsal view of mandibular fracture repaired with crossed IM pins.

Figure 8: Dersoventral view of a bilateral fracture of the mandibles treated with transfixation pins that are secured with tubing filled with methylmethacrylate.

Figure 9: Lateral view of a mandibular fracture treated with a small bone plate. B. Dorsoventral view.