Ulnar notch of the radius

Ulnar notch of the radius

The Ulnar Notch of the Radius is a small, shallow depression located on the medial side of the distal end of the radius bone in the human body. It is also known as the sigmoid notch and is an important anatomical structure in the forearm.

Anatomy

The ulnar notch of the radius is situated on the lower end of the radius, near the wrist, and is concave in shape. It articulates with the head of the ulna, forming the distal radioulnar joint. This joint allows for the rotation of the forearm at the wrist.

Function

The primary function of the ulnar notch of the radius is to form the distal radioulnar joint with the head of the ulna. This joint allows for the rotation of the forearm, enabling movements such as pronation and supination.

Clinical Significance

Injuries or abnormalities of the ulnar notch can lead to a range of clinical conditions. For example, fractures involving the ulnar notch can disrupt the distal radioulnar joint, leading to limited forearm rotation and wrist movement. Conditions such as Rheumatoid arthritis can also affect the ulnar notch, leading to deformity and loss of function.

See Also

• Radius (bone)
• Ulna
• Distal radioulnar articulation