Total hip replacements are most often done to provide relief for severe arthritis, fractures, and some bone abnormalities. Patients who are candidates for total hip replacement surgery generally have: severe pain that impedes work and everyday activities; pain that cannot be managed by anti-inflammatory medications, canes or walkers; or significant stiffness of the hip.
Total hip replacement surgery is a major surgery and there are some potential risks that should be discussed with your doctor. Some patients recover sooner than others depending on age, health status, and response to rehabilitation. The average time for full recovery is about six to 12 weeks and varies with each patient. Physical therapy begins while the patient is still in the hospital and continues either at home or in a specifically designated rehabilitation unit. For a hip replacement, the patient has some therapy in the hospital but none for six weeks at home. However, at the six-week clinic visit, if the patient requires therapy, it is initiated then.
Total Hip Replacement
Hip replacement consists of the replacement of the femoral (thigh bone) head and the acetabulum, or socket of the pelvis. In order for the surgeon to do this, five components are implanted where the arthritic bone once was.
Acetabulum (hip socket):
- After removal of the arthritic femoral head, the surgeon shaves away arthritis present in the socket. They then press-fit a cup into the pelvis. A screw may be placed based on stability of the cup.
- A high-grade polyethylene liner is then placed into the cup to allow for smooth movement between the cup and the femoral head.
Femur (thigh bone):
- The femur is then prepared to receive a stem. This stem will hold the femoral head in place and is placed in the bone space down the femur.
- A neck is placed on the end of this stem to accept the new femoral head.
Knee replacement surgery works best for patients with severe arthritis throughout the knee. This is seen most often in older adults, but can also occur in younger patients due to a significant injury or infection. When arthritis knee pain severely limits the ability to walk, work or perform the simplest of tasks, knee replacement should be considered.
Keeping your weight down is good for your knee and your overall health. Patients should make an effort to begin a preoperative program of exercise. Simple isometrics (muscle tensing exercises) help strengthen your leg muscles in preparation for postoperative walking.
Knee replacement can correct the knee problem, but muscles remain weak and will only be strengthened through regular exercises. Knee replacement surgery patients require physical therapy to regain range of motion and strengthen muscles. This therapy begins in the hospital with a physical therapist and continues thereafter.
Due to advancements in pain management, the surgical team is able to keep patients very comfortable after surgery. While there is pain associated with this procedure, it can be controlled and is only temporary.
Total Knee Replacement
For a total knee replacement, there are three components that will likely be replaced. These include the head of the femur (thigh bone), surface of the tibia (shin bone), and the underside of the patella (knee cap).
Femur (thigh bone):
- The osteoarthritis that was present on the surface of the bone is removed and the bone is shaped to accept a new component. This component is cemented to the existing bone at the end of the thigh bone.
Tibia (shin bone):
- Like the femur, the tibia is cut, removing any arthritis present on the surface or sides. A component is then cemented down onto this bone.
Patella (knee cap):
- On the undersurface of the knee cap arthritis may be present. If so, this arthritis is shaved off and a new surface is cemented in allowing for movement along the surface of the femoral component.
- A high-grade polyethylene liner is placed between the femoral and tibial components to provide articulation and stability of the new joint.