Computed tomographic arthrography of the coxofemoral joint in horses

<b>Background</b>: Investigation of pathology relating to the coxofemoral joint (CFJ) in horses includes intra-articular analgesia and diagnostic imaging using ultrasonography, radiography, scintigraphy, and computed tomography (CT). While CT arthrography has been described for diagnosing intra-articular ligament and cartilage injuries in different equine joints, the use of CT arthrography in the CFJ has not previously been described. <b>Objective</b>: To evaluate CT arthrography for visualization of articular cartilage and intra-articular ligaments of the equine CFJ, and to compare two contrast volumes. <b>Study design</b>: Cadaver study. <b>Material and methods</b>: Coxofemoral joint CT arthrography was performed in ten equine cadavers. Two contrast volumes (30 mL and 50 mL using a 1:1 concentration of 240 mg Iodine /mL and 0.9% NaCl) were used to investigate the visualization of the ligament of the head of the femur, the accessory ligament of the femur, the acetabular labrum, the femoral head cartilage, and joint distension. <b>Results</b>: The ligament of the head of the femur and the accessory ligament of the femur could not be distinguished from each other and were evaluated as a single structure. These ligaments, together with the caudal aspects of the acetabular labrum and the femoral cartilage, were consistently visualized along with joint distension. Visualization of the cranial aspect of the acetabular labrum and the cranial aspect of the femoral cartilage was limited. No significant differences in visualization scores between contrast volumes were identified. <b>Main limitations</b>: Use of cadaver specimens without pathology and lack of comparison with other imaging modalities. <b>Conclusions</b>: CT arthrography of the CFJ enables visualization of intra-articular ligaments and caudal joint structures, although assessment of cranial structures may be limited