👉 The inner fluid, also known as synovial fluid, is a viscous, lubricating substance found within the cavities of joints. It acts as a cushion and lubricant, reducing friction between the articular cartilage surfaces during joint movement. This fluid is primarily composed of water, but also contains proteins, hyaluronic acid, and various electrolytes that help maintain joint health by providing nutrients to the cartilage and facilitating smooth, pain-free motion. Synovial fluid continuously circulates through the joint, replenished by the synovial membrane that lines the joint capsule.
