Ligaments are tough, ropy fibers that connect one bone to
another. The four ligaments of the knee connect the upper leg bone (femur) to
the lower leg bone (tibia) and stabilize knee movement.
- The anterior cruciate ligament (ACL) and the
posterior cruciate ligament cross inside the center of the knee joint and
stabilize front-to-back knee movements.
- The medial collateral
ligament and the lateral collateral ligament connect the leg bones at the sides
of the knee and stabilize side-to-side movements.