Comparison of Conventional Radiography and Computed Tomography in Horses with Carpal Slab Fractures

Introduction
Evaluation of the extent of injury in carpal slab fractures can be difficult on radiographs since the carpal bones overlap considerably. Computed tomography (CT) offers a clear advantage as regions of interest can be evaluated without the superimposition of structures. Our aim was to describe the normal CT anatomy of the third carpal bone (C3) and to compare radiography and CT in the evaluation of carpal slab fractures in horses.

Material and methods
CT images of the carpal bones from 16 Thoroughbred (TB) racehorses (group 1) that were euthanased at various stages of training for reasons other than carpal disease were evaluated and CT anatomy of C3 was described. Radiographs and CT images of TB racehorses with carpal slab fractures (group 2) were evaluated and compared.

Results
Group 1 horses: CT revealed sclerosis in the radial (RaF) and intermediate (InF) facets that increased in extent and severity with exercise and if additional lesions were present. Vascular channels were evident dorsally and in the palmarolateral aspect of the RaF. Lesions included partial (n=5) or full thickness (n=5) subchondral bone (SCB) erosions, medullary lucencies (n=3), and incomplete fracture (n=2).  [...]