The difference between the hip joint and the femoral head in terms of subordination is that the femoral head is part of the hip joint, which is located at the top of the hip bone, or what people call the top of the thigh, and it is also the deepest and most concave of all the joints in the body. The hip joint is a concave ball-shaped joint, which makes it very strong and flexible, and it is also the joint that carries the most weight in the body. The femoral head is the most important part of the hip joint, and it works together with the acetabulum on the opposite side to allow the leg to move. However, the hip joint contains not only the femoral head and the acetabulum, but also many soft tissues, such as the surrounding ligaments, muscles, blood vessels, nerves, joint capsule and other tissues, which make the hip joint less prone to dislocation, so the femoral head is actually a part of the hip joint.