How are oxygen and nutrients primarily supplied to the hyaline cartilage on the articulating surfaces of a synovial joint?

The primary method for supplying oxygen and nutrients to hyaline cartilage on the articulating surfaces of a synovial joint is through synovial fluid. Hyaline cartilage, which covers the ends of bones in synovial joints, is avascular (lacking blood vessels) and therefore cannot receive nutrients directly from the bloodstream.

Synovial fluid, produced by the synovial membrane, serves several crucial functions in the joint environment. It not only lubricates the joint, reducing friction during movement, but also acts as a medium through which oxygen and nutrients are diffused directly to the avascular cartilage. This fluid contains various components, including hyaluronic acid and lubricin, which help maintain the viscosity and elasticity of synovial fluid, ensuring effective nutrient transport.

This mechanism is vital because it allows the cartilage to remain healthy and functional despite its lack of direct blood supply, highlighting the importance of synovial fluid in joint health and physiology. Other options, such as blood vessels or lymphatic fluid, do not directly supply the cartilage with nutrients in this context, as the cartilage does not have a direct blood supply or lymphatic drainage. Articular cartilage itself is the tissue in question, but it does not supply itself with oxygen or nutrients.