forearm

forearm, region of the upper limb located between the elbow and the wrist, consisting of two long bones—the radius and the ulna—that run parallel to one another. These bones are connected by an interosseous membrane and provide structural support for the muscles, tendons, and ligaments that help control fine movements of the wrist, hand, and fingers.

The forearm contains both flexor muscles and extensor muscles, which enable a wide range of precise movements. It is also traversed by major nerves, such as the median, ulnar, and radial nerves, and by blood vessels, including the radial and ulnar arteries.

Functionally, the forearm controls motor movements that are highly precise and that often involve strength, such as those that occur in gripping, or complex twisting motions, such as in pronation (rotating the palm downward) and supination (rotating the palm upward). Many of these movements are essential for performing everyday activities.