Which bone forms the kneecap joint?

The kneecap joint, also known as the patellofemoral joint, is primarily formed by the patella, which is the bone commonly referred to as the kneecap. The patella is a small, flat, triangular bone that sits in front of the knee joint and serves several crucial functions. It protects the knee joint and improves the leverage of the thigh muscles, aiding in the extension of the knee.

The patella articulates with the femur, which allows for smooth movement during activities such as walking, running, and jumping. Its unique position provides added mechanical advantage to the quadriceps muscle by increasing the angle at which the muscles act on the tibia, thereby enhancing the efficiency of knee extension.

While the fibula, tibia, and femur are all components of the knee joint structure, it is the patella that specifically forms the kneecap joint, reinforcing its significance in knee mechanics and overall leg movement.