Definitions

Cartilage:
The thin smooth protective lining of the bone inside the joint. It is responsible for smooth movement, shock absorption, and nutrition of the joint.

Chrome Cobalt:
A material (alloy) frequently used to make artificial components.

CPM Machine:
A device that comfort- ably supports the leg, while continuously bending the knee. Hence CPM - Continuous Passive Motion.

Dislocation:
This occurs if the hip pops out of the socket. The hip will need to be replaced into its normal position under anesthetic.
Femoral Prosthesis:
The artificial component that replaces the head of the femur (thigh bone).

Femur:
The thigh bone. The upper end forms the hip joint. Methyl Methacrylate: The "cement" used to pro- vide firm fixation of an implant within the bone.

Osteoarthritis:
Wear and tear changes in a joint. The cartilage lining surface becomes worn away, causing pain and stiffness.

Patella:
The kneecap.

PMMA:
This stands for poly- methyl-methacrylate. It is the cement used to bond the knee replace- ment in the bone.

Press Fit:
The tight fit of a metal prosthesis into bone. This improves fixation and the probability that bone will grow into the prosthesis.

Prosthesis:
A metallic or plastic device that provides an artificial substitute to replace the removed bone.

Thrombosis:
A blood clot in the veins. This may occur in the legs or pelvis following major surgery.

Tibia:
The leg bone. The long bone between the knee and the ankle.

Titanium:
An essentially pure metal that is more flexible than chrome cobalt. It is more commonly used in non- cement hip replacements.

Total Hip Replacement:
The operation in which the upper part of the thigh bone and its socket are replaced by an artificial joint.

Total Knee Replacement:
The operation in which a diseased knee joint is replaced by an artificial joint.