The capitulum is which option?

The capitulum is which option?

• A. Capitulum
• B. Olecranon process
• C. Radial head
• D. Ulnar head

Answer: (A)

The capitulum is the rounded articular surface on the distal humerus that forms the elbow joint with the head of the radius. It sits on the lateral side of the distal humerus and serves as the articulating partner for the radial head. That’s why it’s not the olecranon process (which is on the ulna), not the radial head itself (which is the proximal end of the radius), and not the ulnar head (the distal ulna). In elbow anatomy, the capitulum specifically pairs with the radial head to allow forearm rotation and flexion–extension movements.

The capitulum is the rounded articular surface on the distal humerus that forms the elbow joint with the head of the radius. It sits on the lateral side of the distal humerus and serves as the articulating partner for the radial head. That’s why it’s not the olecranon process (which is on the ulna), not the radial head itself (which is the proximal end of the radius), and not the ulnar head (the distal ulna). In elbow anatomy, the capitulum specifically pairs with the radial head to allow forearm rotation and flexion–extension movements.