Hip Implants
What are Hip Implants?
Hip implants are artificial devices that form the essential parts of the hip joint in a hip replacement surgery. The hip implants vary by size, shape, and material. Various components of a hip implant may be used for a hip replacement surgery. The components used may depend on the extent of damage to the hip joint, and the preference of your orthopedic surgeon.
What are Hip Implants composed of?
Implants are made of biocompatible materials that can be accepted by your body without producing any rejection response. Implants can be made of metal alloys, ceramics or plastics, and can be joined to the bone. The metals used include stainless steel, titanium, and cobalt chrome, and the plastic used is polyethylene.
Components of a Hip Implant
The components of a hip implant replicate the natural shape and structure of the ball-and-socket joint of the hip. The components used may depend on the size of your body and vary from patient to patient. A total hip replacement implant has three parts:
- Stem: The stem fits into the femur.
- Ball: The ball replaces the spherical head of the femur.
- Cup: The cup replaces the worn-out hip socket (acetabulum).
Types of Hip Implants
Although there are many combinations of bearings, Dr. Steele prefers ceramic on polyethylene as it has the best wear characteristics and lowest risk of complications.
Types of Implant Fixation
Depending on your age and activity level, your surgeon may recommend any of the available three types of implant fixation.
- Cementless fixation: Cementless implants are coated with a porous material. They attach to the new bone that grows to the surface of the implant via bone ingrowth.
- Cemented fixation: In cases of poor femoral bone, sometimes the femoral component is cemented into place. The bone cement is made from a special polymer called polymethylmethacrylate (PMMA).
