The radius is the lateral bone of the forearm, on the thumb side. Its head articulates with the humerus and ulna at the elbow and its expanded distal end forms most of the wrist joint with the carpal bones. It rotates around the ulna during pronation and supination.
| Type | Long bone. |
|---|---|
| Location | Lateral (thumb side) forearm. |
| Landmarks | Head, neck, radial tuberosity, styloid process, dorsal (Lister) tubercle, ulnar notch. |
| Articulations | Humerus (capitulum), ulna (proximal and distal radioulnar joints), scaphoid and lunate. |
| Muscle attachments | Biceps brachii, supinator, pronator teres, pronator quadratus, brachioradialis, flexor digitorum superficialis and others. |
3D model: BodyParts3D (CC BY 4.0), adult male reference anatomy. Highlighted structure shown with nearby bones for context.
During pronation the radius crosses over the ulna, pivoting around the proximal and distal radioulnar joints.
A fracture of the distal radius with dorsal displacement, usually after a fall on an outstretched hand.
The lateral (thumb) side in the anatomical position.
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