Knee Anatomy

The knee is the largest joint in the body and made up of the femur, the tibia and the patella (knee cap). All of these bones are lined with surface cartilage (articular cartilage). The knee joint is surrounded by a capsule that produces a small amount of lubrication (synovial) to help with smooth motion. The muscles of the thigh also assist in stabilising the knee.

Articular Cartilage:
the smooth lining that lines the three bones of the knee joint. Provides a smooth, low friction surface for the knee to move on. Acts like a 'shock absorber'.

Collateral Ligaments: The medial (inner) and lateral (outer) collateral ligaments stabilise the knee and support it from excessive sideways movement.

Cruciate Ligaments: The anterior (internal) and posterior (external) cruciate ligaments support the knee from buckling (giving way).

Ligaments: stabilise the knee both inside and outside the joint.

Menisci: two floating cartilages that lie between the tibia and femur that act as 'shock absorbers' and help stabilise the knee. The medial (inner) meniscus and the lateral (outer) meniscus rest on the surface of the tibia and are mobile. The meniscus function to distribute body weight across the knee joint.

Patella: the knee cap

Synovial: fluid that acts as a lubricant to help with smooth motion.