An 11-year-old spayed female Rottweiler was evaluated for progressive lameness of the right forelimb of 8 weeks' duration; the limb was non–weight-bearing for 4 weeks' duration. The dog was housed outdoors only, its vaccination status was not adequate, and it did not receive heartworm preventative.
Abnormalities detected during physical examination included a non–weight-bearing lameness of the right forelimb and a firm swelling (approx 13 × 10 × 10 cm) extending from the distal third of the humerus to the proximal aspects of the radius and ulna. Flexion of the elbow joint elicited signs of pain. Results of a CBC