What is the main function of the annular ligament?

The annular ligament primarily functions to allow the head of the radius to rotate. Located at the elbow joint, this ligament encircles the radial head and secures it in place while permitting rotational movements that are essential for the forearm's pronation and supination. This rotational capacity is critical for various activities that involve turning the hand, such as using a doorknob or typing.

The annular ligament’s design is such that it adds stability to the joint while enabling the dynamic movement of the radius around the ulna. This ability to facilitate smooth motion without interference is essential for the proper function of the elbow and forearm during various activities.

Understanding the role of the annular ligament also highlights the importance of ligamentous structures in joint mechanics, particularly in allowing for mobility while maintaining stability.