Anatomy means the 'shape' of the structures in the body, and how the different parts correspond to one another.
The anatomy of the knee seems quite simple, but the 'functional anatomy', ie how the pieces operate together, is quite complex.
The knee joint is really three separate joints - the thighbone (femur) has two rounded knuckles (condyles) and each of these articulates with a flattened condyle on the shinbone (tibia). Together these are termed the 'tibio-femoral joint'. The thinner fibula bone at the side of the tibia does not form part of the knee joint itself. At the front of the knee, the kneecap (patella) articulates with the femur, lying in a shallow groove called the trochlea.
Wedged between the two bones on each side of the joint is a shock absorber or meniscus. In the interior of the joint two thick ligaments (cruciate ligaments) join the tibia and femur, and stabilize their forwards and backwards movement in relation to one another. At each side the collateral ligaments limit sideways bending of the joint.
Enclosing and sealing the cavity of the knee joint is a fibrous capsule.
Relevant resources on this site: