Microangiography of the humeral condyle in Cocker Spaniel and non-Cocker Spaniel dogs

The purpose of this study was to evaluate the blood supply to the humeral c ondyle of dogs and compare the blood supply of Cocker Spaniel dogs to non-C ocker Spaniel dogs. We hypothesize that there is a congenitally altered blo od supply of the humeral condyle in some Cocker Spaniels when compared to t he blood supply of the humeral condyle in other breeds of dogs, which leads to abnormal ossification between the medial and lateral aspects of the hum eral condyle, and predisposes them to fracture and delayed healing. Microangiography was performed on four Cocker Spaniel and four non-Cocker S paniel dogs of similar size and weight. Qualitative and quantitative evalua tion of the microangiographs of the humeral condyles revealed a decreased v ascular density in the medial, midcondylar and lateral aspects of the condy le in the Cocker Spaniel dogs compared to the non-Cocker Spaniel dogs. This decreased vascular density may play a role in the increased incidence of h umeral condylar fractures in the adult Cocker Spaniel dog without any or on ly minor trauma, and in the delayed healing seen in association with these fractures.