Upper Limb

Humerus

The only bone of the upper arm; long bone between shoulder and elbow.

Function of Humerus

Connects scapula to radius/ulna and supports arm movement.

Head of humerus

Rounded top part of the humerus.

Function of Head of humerus

Fits into the glenoid cavity to form the shoulder (ball-and-socket) joint.

joint, allowing a wide range of motion.

Greater tubercle

Large bump on the side (lateral) of humerus near the head.

Function of Greater tubercle

Muscle attachment site for arm movement.

Lesser tubercle

Smaller bump on the front (anterior) of the humerus.

It serves as a muscle attachment site for the subscapularis muscle.

Function of Lesser tubercle

Attachment site for rotator cuff muscles.

Intertubercular groove

Groove between greater and lesser tubercles.

Function of Intertubercular groove

Holds the tendon of the biceps brachii muscle.

Capitulum

Round knob on the lateral distal humerus.

Function of Capitulum

Articulates with the head of the radius for forearm rotation.

Allows for flexion and extension of the elbow.

Trochlea

Spool-shaped part on the medial distal humerus.

Function of Trochlea

Connects with the ulna’s trochlear notch for elbow movement.

Epicondyles (medial and lateral)

Bumps on both sides just above the capitulum and trochlea.

Function of Epicondyles

Muscle attachment sites for hand and finger movement.

Radius

Lateral (thumb side) bone of the forearm.

Function of Radius

Allows the forearm to rotate (pronate/supinate).

Head of radius

Rounded top end of the radius.

Function of Head of radius

Articulates with the capitulum to allow forearm rotation.

Ulna

Medial (pinky side) bone of the forearm.

Function of Ulna

Forms hinge joint at elbow with humerus; allows flexion/extension.

Olecranon (process)

Big bump on the back of the ulna (elbow tip).

Function of Olecranon

Attachment for arm muscles; makes the point of the elbow.

Trochlear notch

C-shaped notch on the ulna.

Function of Trochlear notch

Articulates with the trochlea of the humerus for elbow movement.

Head of ulna

Rounded end at the bottom of the ulna near the wrist.

Function of Head of ulna

Articulates with wrist bones (carpals).