Characteristics of Fractures of the Appendicular and Axial Skeletons in Rabbits and Hares: A Retrospective Study

The frequency and characteristics of fractures may vary according to the environment. The present study aimed to assess the fractures of the appendicular and axial skeletons in rabbits (Oryctolagus cuniculus) and hares (Lepus sp.) presented at a veterinary teaching hospital. Medical records and radiographs were retrospectively analyzed over eight years. Twenty-six pet rabbits and five free-ranging hares were enrolled in this study. Twenty-one of them had fractures in the appendicular skeleton, nine in the axial skeleton, and one in both. The fractures were related to traumatic events, such as being hit by a vehicle (22.58%), falling (12.9%), being attacked by another animal (12.9%), and having a paw stuck in a hole (3.22%); 48.38% had an unknown cause. Long bone fractures were found in the humerus (n=2), radius/ulna (n=1), femur (n=5), and tibia (n=12). Fractures involving the distal aspects of the limbs included the tarsus (n=1) and metatarsus (n=2) bones. Except for one rabbit, all of the others had unilateral fractures. Fourteen presented closed fractures, and nine were open fractures. All these fractures were complete, 56.52%% simple, and 43.47% multifragmental. The procedures used included osteosynthesis (42.85%), external coaptation (28.57%), amputation (14.28%), euthanasia (4.76%), and two animals died (9.52%). The fractures of the axial skeleton included the vertebral column (n=6), mandible (n=3), and pelvis (n=2). Five fractures were treated conservatively, and the rabbits were euthanized in four cases. The fractures resulted from a traumatic episode, which had an unknown origin in most of the cases, involving mainly the appendicular skeleton, being the tibia the bone most affected.