What is uln?

The ulna is one of the two long bones in the forearm; the other is the radius. It is located on the medial (pinky finger) side of the forearm. The ulna plays a crucial role in the movement and stability of the elbow and wrist joints.

Key features of the ulna include:

• Olecranon: This is the bony prominence at the posterior aspect of the elbow, commonly known as the "elbow bone." It fits into the olecranon fossa of the humerus.

• Coronoid Process: A triangular eminence projecting forward from the proximal end of the ulna. It fits into the coronoid fossa of the humerus when the elbow is flexed.

• Trochlear Notch: A large, concave depression that articulates with the trochlea of the humerus, forming part of the elbow joint.

• Radial Notch: A small, smooth, articular facet on the lateral side of the coronoid process where the head of the radius articulates.

• Ulnar Head: The distal end of the ulna, which articulates with the radius at the distal radioulnar joint and also has a small articulation with the carpal bones of the wrist.

• Ulnar Styloid Process: A small, conical projection located at the distal end of the ulna. It provides attachment for ligaments of the wrist.

The ulna contributes significantly to elbow joint stability and provides attachment points for several muscles of the forearm, involved in flexion, extension, pronation, and supination movements. Fractures of the ulna are common, particularly in the olecranon and coronoid process, and can affect elbow and forearm function.