Anatomic and radiographic appearance of a sesamoid bone in the tendon of origin of the supinator muscle of dogs.

Radiologic and anatomic studies of the elbow of 100 dogs of 17 different breeds showed that a sesamoid bone may be located in a constantly present sesamoid cartilage associated with the tendon of origin of the supinator muscle. The sesamoid was observed in 31% of the radiographs of 100 supinator tendons dissected from 50 of the dogs. The bone was usually bilateral and was best demonstrated in craniocaudal medial-to-lateral oblique radiographs of the elbow where it articulated with the craniolateral aspect of the head of the radius.