What is the function of the proximal radioulnar joint?

The function of the proximal radioulnar joint is primarily to facilitate forearm rotation. This joint is located between the radius and the ulna, near the elbow, and it plays a crucial role in allowing you to perform movements such as pronation and supination of the forearm. During pronation, the radius rotates over the ulna, while during supination, the radius returns to its original position parallel to the ulna. This ability to rotate is essential for various activities, such as turning a doorknob or using hand tools.

The other options refer to functions that are not associated with the proximal radioulnar joint. Wrist flexion primarily involves movements at the wrist joint itself and does not require the actions of the proximal radioulnar joint. The proximal radioulnar joint does not support shoulder movement, as shoulder mechanics are largely dictated by shoulder joints and muscles surrounding them. Additionally, while the elbow extension involves the radius and ulna, it is not the primary purpose of the proximal radioulnar joint; its main function revolves around the rotation of the forearm.