Print. The kneecap (the patella) is a triangular bone at the front of the knee. Several tendons and ligaments connect to the kneecap, including ones attached to the upper leg (femur) and lower leg (tibia) bones.rint. The kneecap (the patella) is a triangular bone at the front of the knee. Several tendons and ligaments connect to the kneecap, including ones attached to the upper leg (femur) and lower leg (tibia) bones.