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What is Total Knee Arthroplasty?

Donn Saylor
Donn Saylor

A total knee arthroplasty is a type of surgery that replaces the worn or injured surfaces of the knee joint with artificial elements. It is performed on patients who experience profound pain and mobility problems associated with osteoarthritis, psoriatic arthritis, rheumatoid arthritis, or knee injuries. The surgery is also known as a total knee replacement and restores the knee's capabilities by implementing artificial joints or prostheses.

While it is a relatively common procedure, knee replacement surgery is often considered a last resort and used when other modes of treatment have been ineffective. Medications, vitamins and supplements, and physical therapy may go a long way in preventing the need for a total knee arthroplasty. If the knee joint continues to degrade, however, this type of surgery has proved to be a successful remedy.

A physician removes cartilage during knee arthroplasty.
A physician removes cartilage during knee arthroplasty.

There are two forms of knee arthroplasty. In a total knee replacement, the worn surfaces of the entire knee are removed and restored with artificial joints. Partial knee replacement is performed on patients with less widespread knee problems and consists of repairing only the damaged parts of the joint, which does not include the knee in its entirety.

A total knee arthroplasty is performed on patients who experience profound pain and mobility problems associated with osteoarthritis, psoriatic arthritis, rheumatoid arthritis, or knee injuries.
A total knee arthroplasty is performed on patients who experience profound pain and mobility problems associated with osteoarthritis, psoriatic arthritis, rheumatoid arthritis, or knee injuries.

When a physician determines the need for a total knee arthroplasty, he or she looks at several important factors in the patient's condition. If all other methods of treatment have failed, and the patient still encounters pain and difficulty in moving around, the doctor may suggest a knee replacement. The doctor looks specifically at the state of the cartilage surrounding the knee joint, which typically is the single most essential aspect of deciding whether or not knee arthroplasty is the next logical step. If the cartilage is greatly diminished or worn out completely, knee replacement is often the only viable option.

Physical therapy may be able to prevent a patient from needing total knee arthroplasty.
Physical therapy may be able to prevent a patient from needing total knee arthroplasty.

During the surgery, parts of the knee muscles are separated from the knee cap. The meeting points of the femur and tibia are then cut to accommodate the prosthetic joint. Cartilage and ligaments are taken out, and the artificial joint is fused onto the bones.

In a typical total knee arthroplasty, the prosthetics used are made of two elements; one section of the prosthesis is metal, commonly titanium or chrome, and the other part is made of the widely-used plastic known as polyethylene. These materials are extremely durable and allow the patient a free range of motion, virtually identical to that of the natural knee.

Total knee arthroplasty has shown impressive results. Several studies have shown success rates that last for 15 years or more after the surgery. Most patients find they are able to resume their previous levels of activity with no major issues after the healing process is complete.

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    • A physician removes cartilage during knee arthroplasty.
      By: Alexandr Mitiuc
      A physician removes cartilage during knee arthroplasty.
    • A total knee arthroplasty is performed on patients who experience profound pain and mobility problems associated with osteoarthritis, psoriatic arthritis, rheumatoid arthritis, or knee injuries.
      By: marilyn barbone
      A total knee arthroplasty is performed on patients who experience profound pain and mobility problems associated with osteoarthritis, psoriatic arthritis, rheumatoid arthritis, or knee injuries.
    • Physical therapy may be able to prevent a patient from needing total knee arthroplasty.
      By: lunamarina
      Physical therapy may be able to prevent a patient from needing total knee arthroplasty.