OSTEOCHONDRITIS-DISSECANS OF THE CANINE TARSAL JOINT

In this presentation, osteochondritis dissecans of the canine tarsal j oint is characterized based on a review of 96 cases in the literature and 123 cases from the Veterinary Medical Data Base. Labrador retrieve rs and rottweilers were most often affected. If breed popularity is co nsidered, the bullmastiff had the highest incidence of tarsal osteocho ndritis dissecans. Most dogs were between six months and one year of a ge; however, 18% were older than two years of age at the time of prese ntation. Females accounted for 53% of the cases of tarsal osteochondri tis dissecans, in contrast with osteochondritis of other joints, in wh ich males predominated. Bilateral lesions occurred in 44% of the dogs, which is less than the reported incidence for osteochondritis disseca ns of other joints. Seventy-five percent of the lesions occurred at th e medial trochlear ridge; most lesions were located in the plantar hal f Radiographic imaging of the lesion may be difficult but can be impro ved via oblique and flexed dorsoplantar projections. Most authors advo cate surgery; however, results after surgery compared with results of conservative therapy make the choice of treatment debatable. The surgi cal approach affects postsurgical function of the joint. Approaches th at avoid osteotomy and desmotomy cause the least morbidity. Prognosis of patients is guarded and depends on several factors, of which size o f the lesion is probably the most important. Radiographic appearance o f the joint does not necessarily correspond with the severity of the l ameness.