Radioulnaarinen

Radioulnaarinen refers to the articulation and relationship between the radius and the ulna, the two bones of the forearm. These bones are connected by a series of joints and fibrous membranes that allow for specific movements of the forearm. The primary radioulnar joints are the proximal radioulnar joint, located near the elbow, and the distal radioulnar joint, found near the wrist. These joints are crucial for supination and pronation, the movements that turn the palm up and down, respectively.

The proximal radioulnar joint is a pivot joint formed by the radial head articulating with the radial notch of the ulna. This articulation is stabilized by the annular ligament, which encircles the radial head. The distal radioulnar joint is also a pivot joint where the head of the ulna articulates with the ulnar notch of the radius. This joint is further stabilized by the triangular fibrocartilage complex (TFCC), a collection of ligaments and cartilage.

Beyond these specific joints, the radius and ulna are connected along their shafts by the interosseous membrane, a broad sheet of fibrous tissue. This membrane provides stability to the forearm, transmits forces between the two bones, and serves as an attachment point for muscles. The coordinated action of these radioulnar structures enables the complex and versatile movements of the hand and wrist.