MODEL RELEASED. Hip replacement surgery. Image 4 of 11. Head of the femur (thigh bone) of a 75 year old woman removed during hip replacement surgery. Retractors are holding back the skin and soft tissues. Hips may need to be replaced due to injury, disease or deformity. This hip is being replaced because of osteoarthritis, a degenerative joint disease that results in the loss of cartilage between the joint and the growth of bone in place of the cartilage. This causes pain, stiffness and loss of mobility. For a sequence of images showing the surgery see M551/450 to M551/460.