the largest joint in the human body. you can aspirate a couple of millilitres of synovial fluid from this joint.
oddly enough, a more complex joint than it seems as it not only allows hinge movement but also some degree of sliding and rotation.
this joint is stabilised by the medial collateral ligament and the lateral collateral ligament externally and, within the joint, by the anterior cruciate ligament and the posterior cruciate ligament.
the knee joint itself is a joint between the femur and the tibia but the fibula and the patella are closely related to the knee joint.
around 80% of all osteosarcomas occur around the knee joint.
a reasonably good webpage for further info: http://www.arthroscopy.com/sp05001.htm