Which layer of the joint capsule is richly vascularized and poorly innervated, serving as an entry point for nutrients to the joint?

• A. Inner layer
• B. Outer layer
• C. Synovial membrane
• D. Hyaline cartilage

Answer: (A)

The nutrient supply to the joint comes through the inner lining of the capsule. That inner layer, the synovial membrane, is richly vascularized, bringing in the blood supply that forms and maintains the synovial fluid. Cartilage itself has no blood vessels, so it relies on diffusion from this fluid for nutrients. Because of its vascular network, the inner layer effectively serves as the entry point for nutrients into the joint. The outer fibrous layer is mainly for structure and has less direct nourishing role, and hyaline cartilage cannot supply nutrients since it lacks vessels and nerves.