What is a ligamentous joint?

A ligamentous joint, also referred to as a syndesmosis, is characterized by a mid-union of bones connected by ligaments, allowing for limited movement. The most common example of this type of joint is found between the ulna and radius in the forearm, where the interosseous membrane connects these two bones. This connection provides stability while still allowing for some movement, such as rotation of the forearm during pronation and supination.

The correct choice emphasizes that a ligamentous joint fundamentally relies on the ligaments for its structure and function, differentiating it from other types of joints. For instance, a joint with a capsule and synovial fluid typically refers to a synovial joint, which allows for a greater range of motion and is distinct from ligamentous joints. Similarly, a joint formed by cartilaginous connections describes a cartilaginous joint, which also limits movement compared to ligamentous joints. Lastly, a freely movable joint refers to a synovial joint that offers a high degree of mobility, contrasting with the limited mobility seen at ligamentous joints.