Joint Compression and Extension
During walking, the knee joint undergoes cyclical compression and extension in response to the gait cycle. As the foot strikes the ground, the knee bears the body's weight and then relaxes as the leg extends.
Cartilage Wear
The joint cartilage undergoes wear and tear with every step. Cartilage is an avascular, aneural, and alymphatic tissue that receives nutrition from synovial fluid. Wear of the cartilage can lead to pain and joint dysfunction.
Production and Drainage of Synovial Fluid
Synovial fluid is continuously produced and drained within the knee joint to lubricate the joint surfaces and reduce wear.
Role of Muscles and Ligaments
The muscles and ligaments surrounding the knee joint are crucial for maintaining joint stability. They help control joint movement with every step, preventing overextension or twisting.
Meniscal Compression and Recoil
The menisci are two C-shaped cartilage pads located between the femur and tibia, which compress and then recoil as the leg extends with each step.
Expansion and Contraction of the Joint Capsule
The joint capsule, a sac-like structure that encloses the entire knee joint, expands and contracts with each step to accommodate knee movement.