Knee

The knee joins the thigh and the lower leg and consists of two articulations: one between the thighbone (femur) and the shinbone (tibia), and one between the knee cap (patella) and the femur. The joint surfaces are lined with articular cartilage, a smooth substance that cushions the bones and enables them to move easily. A thin tissue layer inside the knee called the synovial membrane releases synovial fluid. This specialized fluid lubricates the knee and reduces friction to nearly zero.

The knee is the largest joint in the human body, but also the one most vulnerable to injury. Injury or disease can disrupt the normal state of knee function resulting in pain, muscle weakness and loss of function.

To learn more about common medical conditions affecting the knee, click the links located in the menu to the upper left.