Knee

Knee, front of the leg where the femur (thighbone) and tibia (shinbone) meet, and the joint itself, covered by the patella, or kneecap. Because the bony surfaces do not match exactly, the knee joint is one of the body's weakest joints. Its strength lies in the number, size, and arrangement of the ligaments, and the powerful muscles and fibrous membranes that pass over the joint and enable it to withstand the leverage of the 2 longest bones in the body.

See also: Joint.