Prosthesis design and construction materials have undergone considerable development since 1960.
The numerous models now available to orthopaedic surgeons are of two main types: cemented prostheses, which are fixed to the host bone by a cement, and non-cemented prostheses, which are fixed by direct integration of the host bone onto the prosthetic surface. The choice of model depends on the quality of the host bone, the patient’s age and the surgeon’s experience.
Regarding the cotyle, most surgeons now choose a non-cemented implant, in which immediate stability is by way of press-fit or pressure on the surrounding bone. The choice of stem, on the other hand, depends on the quality of the bone: in the case of osteoporotic bone (poor bone quality) it’s advisable to choose a cemented implant. Hip replacement models used today also differ in terms of the materials used for the femur head-cotyle insert coupling, including metal-polyethylene, ceramic-polyethylene, ceramic-ceramic and metal-metal.
Ceramic-ceramic and metal-metal couplings allow the use of bigger femur heads and provide greater articulation of the operated hip because of their mechanical strength characteristics.