What is the Difference Between Radius and Ulna?

The radius and ulna are two long bones that make up the forearm, extending from the elbow to the wrist. They have some differences in terms of their structure and function:

• Position: In the anatomical position, the radius is found in the lateral forearm, while the ulna is found in the medial forearm.
• Length: The radius is shorter than the ulna.
• Structure: The radius has a small proximal end that articulates with the humerus, and a broad distal end that articulates with the carpal bones at the wrist. The ulna, on the other hand, has a large proximal end that articulates with the humerus and the head of the radius, and a distal end with a head that articulates with the distal radius.
• Shaft: The radius has a slightly curved shaft, while the ulna has a straighter shaft.
• Mobility: The radius is thicker than the ulna.

The primary function of the radius is to work with the ulna at the elbow to produce pronation and supination, allowing us to rotate our palms towards the ceiling and down towards the floor. The primary function of the ulna is to articulate with the humerus to form the elbow joint. Both bones participate in joints and provide surfaces for the attachment of several upper limb muscles, enabling proper mobility of the upper extremity.

Comparative Table: Radius vs Ulna

The radius and ulna are long bones that make up the forearm, extending from the elbow to the wrist. They have several differences in terms of structure and function. Here is a table summarizing the differences between the radius and ulna:

The radius and ulna work together to provide proper mobility and support for the upper extremity, enabling smooth rotation and movement at the wrist and elbow joints.