Osteoarthritis of the knee is a disease of the articular cartilage or gliding surfaces of the knee. Over time, the smooth, glistening cartilage surface of the knee wears out. It becomes roughened and worn which leads to pain and stiffness. This can lead to complete wear of the cartilage surface and to contact of bone on bone of the femur and tibial surfaces.
Knee replacement surgery involves removing the diseased, worn-out cartilage and replacing it with metal and plastic components which take over the role of the gliding surfaces of the knee. Often both the inside and the outside compartments of the knee as well as the kneecap (patella) are involved and each needs to be replaced.
Occasionally only one side of the knee is involved, usually the inner side (the Medial side). If all the ligaments of the knee are still working normally and certain other criteria are met then a
Unicompartmental Knee Replacement (UKA) may be used. Unicompartmental Knee Replacement is an excellent operation when used in the right setting, however if the wrong indications are present then it is reasonable to expect that the UKA may not last as long as one would hope.