Individual differences | Methods | Statistics | Clinical |
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| |Gray's||subject #84 321| |Left elbow-joint, showing anterior
and ulnar collateral ligaments.| The bony prominence at the very
tip of the elbow is the olecranon process of the ulna. Two main
movements are possible at the elbow: - The hinge-like bending
and straightening of the elbow (flexion and extension) happens
at the articulation ("joint") between the humerus and the ulna.
- The complex action of turning the forearm over (pronation or
supination) happens at the articulation between the radius and
the ulna (this movement also occurs at the wrist joint). In the
anatomical position (with the forearm supine), the radius and
ulna lie parallel to each other. During pronation, the ulna
remains fixed, and the radius rolls around it at both the wrist
and the elbow joints. In the prone position, the radius and ulna
appear crossed. Most of the force through the elbow joint is
transferred betw