Long Bone Fractures in Impala (Aepyceros melampus): A Classification System and Review of 55 Cases.

Objective:  The purpose of this study was to introduce a modified-Unger fracture classification in impala and report the findings of 58 long bone fractures classified according to this system.

Methods:  This was a retrospective radiographical study evaluating 122 radiographs of 58 long bone fractures in 55 impala. The Unger fracture classification was modified and fracture illustrations for the metacarpal and metatarsal bones added. Each fracture was classified and assigned a four symbol α-numeric code using our classification. The patient signalment, skeletal maturity, fracture-associated soft tissue changes, presence of fissure lines, periosteal reaction and cause of the fracture were recorded.

Results:  The overall fracture distribution based on location, found tibial ( = 17) fractures to be the most common fractured long bone. When combined, the majority of fractures involved the metacarpal and metatarsal bones ( = 23). Forty five of 58 fractures occurred in the diaphyseal bone segment. In all long bones, the distribution based on complexity was simple ( = 27), wedge ( = 16) and multi-fragmentary ( = 15) fractures. Thirty one of 58 fractures were open and fissure lines were detected in 20 of 58 fractures.

Clinical Significance:  Our modified-Unger fracture classification was applicable in classifying 58 impala long bone fractures. This classification should provide the basis for further advances in veterinary and comparative ungulates, and particularly the antelopes, orthopaedics and traumatology.