Joint replacement surgery has become an established treatment for patients with severe arthritis that no longer responds to conservative measures.  This article discusses some general concepts regarding this procedure.

The two most common joints that are replaced for arthritis related problems are the hip and the knee.

Two major types of joint replacements are available.

The first type is the cemented joint. In this procedure, the artificial joint is glued to the natural bone.

The other type is the uncemented. Here, the replacement joint is covered with a porous textured material and natural bone then grows and attaches to the joint replacement.

Roughly, 90 per cent of artificial joints last 10 to 15 years after which a second joint replacement- a 搑evision??is then required.

Cemented joints are generally offered to patients with weaker bones- such as occurs with osteoporosis- because the cement holds the artificial joint in place more firmly. These types of replacements are more difficult to revise than uncemented ones because the cement needs to be removed. Cemented artificial joints are generally used for frailer and older individuals who are likely to have less bone mass and are also less likely to require a revision procedure. The main problem with cemented joints is that come of them loosen over time and need revision.

Uncemented artificial joints are a better choice for younger healthier more active people. These individuals are more likely to require a revision procedure down the road. They also have denser bones which keeps the artificial joint anchored more firmly. Approximately 30 per cent of patients who receive an uncemented joint for hip arthritis develop thigh pain. This problem may last for as long as two to three years after surgery. Uncemented hip replacements take longer to heal and patients require a longer period of time before they can begin to weight bear. Too much stress on the uncemented joint too early leads to loosening.

Full recovery takes about 6 months for both procedures.

Serious complications occur in about 5 per cent of people receiving joint replacements. The most frequent is thrombophlebitis (blood clots in the legs). Attempts to prevent this complication have been successful in many instances. These include the use of aspirin, heparin or other blood thinners, and leg compression devices. These leg compression units inflate and deflate so that the leg is constantly massaged.

Another potentially serious complication is infection. This side effect requires both removal of the artificial joint as well as treatment with intravenous antibiotics. The treatment requires several weeks of hospitalization. A new artificial joint can be implanted once the infection has been totally cleared. Patients with artificial joints must guard against infection for at least two years after their surgery by taking oral antibiotics before dental and urinary tract procedures. Even minor infections should be treated aggressively with antibiotics.