Final answer:
The anatomy of the forearm and the proximal and distal radioulnar joints.
Step-by-step explanation:
The subject of this question is the anatomy of the forearm and specifically the proximal and distal radioulnar joints. The proximal radioulnar joint is an articulation between the head of the radius and the radial notch of the ulna, allowing for rotation of the radius during pronation and supination of the forearm. The distal radioulnar joint is found between the head of the ulna and the ulnar notch of the radius.