Movement at the proximal radio-ulnar joint
This joint, together with the distal radio-ulnar joint, allows for the pronation and supination of the forearm.
The articular circumference of the radial head (upper end of the radius) fits in the radial notch of the upper end of the ulna and moves in a rotational motion.
The supinating and pronating movements are performed in the range of 90° and 85°, respectively.