American Academy of Professional Coders (AAPC) 2026 – 400 Free Practice Questions to Pass the Exam

In the context of synovial joints, the joint capsule is a structure that encases the joint, providing stability and allowing for movement. The joint capsule comprises two layers: an outer fibrous layer made of fibrous connective tissue, which helps in anchoring the joint, and an inner synovial membrane that lines the joint cavity and produces synovial fluid for lubrication.

Articular cartilage is a key component of the joint, covering the ends of the bones where they meet in the joint, facilitating smooth movement. The joint cavity is the space within the joint capsule that contains synovial fluid, allowing for a lubricated environment that reduces friction during joint movement.

Skeletal muscle, on the other hand, is not a part of the joint capsule. Instead, it functions to move the bones at the joint through contraction. Thus, it does not contribute to the structural integrity or function of the joint capsule directly, which is why it is identified as the component that is not part of the joint capsule in synovial joints.