Labrador retrievers and Rottweilers are the two breeds most commonly affected with osteochondritis dissecans of the hock. The majority of dogs affected are less than one year of age and are large breeds. Males and females are equally affected. Clinical signs include lameness, an extended hock joint, thickening of the joint, muscle atrophy, and reduced range of motion accompanied by pain.
Bilateral lesions are common.
Multiple different radiographic views may be needed to establish the diagnosis. Surgical removal of the loose cartilage flap is the most common method of treatment. Osteochondrosis is a failure of the normal endochondral ossification process that occurs in young growing animals. Enlargement of the epiphysis of the bone is a result of endochondral ossification in the articular cartilage. In osteochondrosis, the endochondral ossification process stops at the hypertrophic layer of cartilage resulting in a thickened area of cartilage.