Humerus anatomy

Head Rounded proximal end that articulates with the scapula.

Anatomical neck Narrow groove surrounding the head.

Surgical neck Narrow region below the tubercles; common fracture site.

Greater tubercle Large lateral projection for muscle attachment.

Lesser tubercle Smaller anterior projection for muscle attachment.

Intertubercular sulcus Groove between the greater and lesser tubercles.

Shaft Long middle portion of the humerus.

Deltoid tuberosity Roughened area where the deltoid muscle attaches.

Radial groove Posterior groove where the radial nerve travels.

Radial fossa Anterior depression above the capitulum; receives radius during flexion.

Coronoid fossa Anterior depression above the trochlea; receives ulna during flexion.

Olecranon fossa Large posterior depression that receives the ulna during extension.

Lateral epicondyle Lateral projection for muscle/ligament attachment.

Medial epicondyle Larger medial projection for muscle/ligament attachment.

Capitulum Rounded lateral surface that articulates with the radius.

Trochlea Pulley-shaped medial surface that articulates with the ulna