The knee joint is the largest and most complex joint in our body. The anatomy of the knee shows the elements that the knee consists of: bones. tendons, and ligaments. The knee connects the upper leg bone to the lower leg bone. Cartilage covers the ends of both leg bones and the underside of the patella, or knee cap. When these surfaces are smooth, the joint glides easily and without pain.
The knee joint, also known as tibiofemoral joint, is essential for everyday activities because it allows flexible movement of the lower leg while supporting the entire body and its weight. As a result of the constant pressure it bears, the knee is vulnerable and prone to injuries.
The knee joins the thigh bone (femur) to the shin bone (tibia). The knee joint has two other bones: fibula – a smaller bone that runs alongside the tibia, and the kneecap, also known as the patella.
With the tendons, the knee bones are connected to the leg muscles that actually move the knee.
Ligaments join the knee bones and provide stability to the knee. There are three groups of ligaments:
- Anterior cruciate ligament – prevents the femur from sliding backward on the tibia
- Posterior cruciate ligament – prevents the femur from sliding forward on the tibia
- Medial and lateral collateral ligaments – prevent the femur from sliding side to side