A percutaneous biopsy technique for the study of endochondral bone formation in the dog was developed. With the dogs under general anesthesia or sedated with a combination of a tranquilizer and a local anesthetic, biopsy specimens were obtained from the proximal growth plate of the humerus with the use of a Jamshidi bone biopsy needle. Biopsy specimens were structurally intact, and contained epiphysis, growth plate, and metaphysis. The procedure proved to be a simple, safe technique, which caused minimal discomfort for the patient and did not affect the growth of the proximal end of the humerus, even after multiple biopsies.

In an anatomic and radiologic study of the clavicle of 50 adult dogs of 10 breeds, the clavicle had ossified in 96% of the dogs. The clavicles studied had various shapes, and each clavicle was attached to the caudomedial part of the clavicular intersection of the bradiocephalic muscle, to the mastoid part of the cleidocephalic muscle, and to 4 radiating bands of connective tissue fasciculi. One band was attached to the caudal border of the scapula and fascia deep to the latissimus dorsi muscle, 1 was attached to the manubrium of the sternum, and 1 each was attached to the epimysia of the superficial pectoral and sternocephalic muscles. We concluded that, during movements of the thoracic limb, the clavicle and the 4 fasciculated connective tissue bands associated with it stabilize the position of the brachiocephalic muscle with relation to the crest of the greater tubercle of the humerus. Also, the fasciculated band attached to the caudal border of the scapula provides protection for nerves from the brachial plexus and axillary blood vessels that supply the thoracic limb.