What is the key feature of extrinsic ligaments in relation to joint structure?

The key feature of extrinsic ligaments in relation to joint structure is that they are located outside of the joint capsule. Extrinsic ligaments play a crucial role in providing additional stability to joints by connecting bones at the joint and limiting excessive movement that could lead to injury. They often attach to the outer areas of the joint formation, distinct from the intra-articular structures such as the joint capsule and synovial membrane.

In contrast, other features mentioned, such as being composed of fibrocartilage or being found within the joint capsule, refer to different anatomical structures, such as menisci or intrinsic ligaments, which are entirely different in both function and location. Being classified as part of the synovial membrane is also inaccurate since the synovial membrane primarily lines the inner surface of the joint capsule and is responsible for producing synovial fluid, rather than providing support like extrinsic ligaments. Hence, the correct understanding of extrinsic ligaments lies in their specific external positioning relative to the joint capsule and their role in joint stability.