Osteochondritis dissecans of the shoulder and tarsus in dogs
6-month-old male Labrador Retriever with left forelimb lameness and pain on shoulder hyperextension. The mediolateral radiograph shows flattening with a radiolucent subchondral defect and sclerosis in the humeral head.
Which statement is correct?
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A. The typical location is the cranial aspect of the humeral head
Shoulder OCD affects the caudal or caudocentral aspect of the humeral head, the main load-bearing area. A cranial lesion should prompt another diagnosis.
B. The cartilage flap is always visible on plain radiographs
The flap is only visible once it has mineralised. Usually only the subchondral defect is seen; the flap is shown by arthrography, CT or arthroscopy.
C. The lesion is typically caudal and often bilateral: also radiograph the contralateral shoulder
Correct. Shoulder OCD mainly affects males of large breeds aged 4–8 months and is bilateral in a substantial proportion, even when lameness is unilateral.
D. The craniocaudal view is the most useful to detect it
On the craniocaudal view the caudal lesion is superimposed. The key view is the mediolateral with the limb pulled cranially; slight oblique views help profile the lesion.
lightbulb Key takeaway
Loose fragments can migrate into the biceps tendon sheath and cause tenosynovitis. In the tarsus, OCD usually affects the medial trochlear ridge of the talus (Labrador, Rottweiler): look for a widened joint space and a flattened contour on flexed and extended dorsoplantar and oblique views, and use CT when in doubt.
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Updated: October 31, 2026 · Educational content for veterinary professionals. It does not replace current clinical guidelines or the judgement of the attending veterinarian.