The hip is a ball-and-socket joint made up of the head of the thigh bone or femur that acts as the ball and fits into the rounded socket of the hip bone or acetabulum. The neck of the femur is the region just below the ball of the hip joint. Fractures to the femoral neck can completely or partially disconnect the femoral head from the rest of the femur. Femoral neck fractures may be either displaced, where the bone is moved out of its original position, or non-displaced, where there is no instability of the bone.