Bones of the Brachium

Medial epicondyle

Larger of the two and has a squared-off caudal border

Body of the humerus

Lies between the two extremities.

Trochlea of the humerus

Lies medial to the ridge and is the larger of the two parts. It has a deep groove in its middle. The trochlea articulates with the radius and ulna.

Capitulum

Much smaller than the trochlea. It lies lateral to the ridge and articulates only with the radius.

Tricipital Line

Only found in canines. The ridge running distally from the caudal end of the greater tubercle of the humeral head.

Radial fossa

The much smaller depression on the cranial aspect of the bone.

Surgical Neck of humerus

The constricted portion of the bone just distal to the tubercles. Most common site of a fracture of the humerus

Olecranon fossa

The depression on the caudal surface of the humerus between these crests. As its name implies, part of the olecranon (proximal end of ulna) occupies this fossa.

Humeral condyle

The distal extremity of the humerus. The articular surface is divided by a ridge into the trochlea and the capitulum. This ridge may be better on the cranial aspect of the condyle.

Intertubercular groove

The groove between the greater and lesser tubercles. The tendon of origin of the long head of the biceps brachii muscle runs in this groove. In the canine, the biceps only has one head.

Greater tubercle of the humerus

The large rounded ridge craniolateral to the head

Teres Major Tuberosity

The roughened area on the medial side of the humerus at the junction of the proximal and middle thirds. The combined tendon of insertion of the teres major and latissimus dorsi muscles insert here. This structure is not present in humans.

Lateral epicondyle

The smaller of the two and has a rounded caudal border

Lesser tubercle of the humerus

The smaller ridge on the medial aspect of the head

Bicipital Groove

This smooth surface starting just distal to the head on the lateral aspect of the bone and curving carniodistally around the bone. It is normally covered by the brachialis muscle.

Deltoid tuberosity

An elongated, thickened bony prominence that is the attachment site for the deltoideus muscle

Humerus

Bony component of the brachium. The proximal extremity articulates with the scapula to form the humeral (or shoulder) joint. The distal extremity articulates with the radius and ulna to form the cubital (or elbow) joint.

Coronoid fossa

Small depression on the anteriomedial aspect of the bone.