When is Knee Arthroplasty (Replacement) Needed?

Helpful Highlights

• Indications for knee replacement are many and related to pain and loss of function.

• Knee surgery is considered when other, less invasive methods are failing to provide relief and restore function.

• Note that many other health and history factors determine whether knee surgery is appropriate.

When your loved one's quality of life suffers due to knee pain and limited function, it may be time for knee arthroplasty (replacement). Signs of declining quality of life include (but are not limited to):

• Inability to get restful sleep because of pain

• Difficulty doing simple tasks such as getting dressed or climbing stairs

• Intractable (uncontrollable) knee pain, stiffness, swelling (maybe warmth)

• Inability to participate in the activities they enjoy

At first, the provider may recommend other treatments such as medicine for pain or inflammation, walking aids, joint injections, and physical therapy. If these measures do not relieve the problems, knee replacement surgery may be necessary to restore function and improve quality of life. 

Indications for knee arthroplasty (replacement)

This surgery is usually performed on adults after other treatments have failed to help. A knee replacement may be needed because of:

• Osteoarthritis - commonly known as wear-and-tear arthritis, osteoarthritis damages the slick cartilage that covers the ends of bones and helps joints move smoothly, and the knee may "give" (weaken suddenly) because the joint is not stable

• Inflammatory arthritis (rheumatoid arthritis, psoriatic arthritis) - caused by an overactive immune system, inflammatory arthritis erodes cartilage and occasionally underlying bone, resulting in damaged and deformed joints

• Post-traumatic arthritis - follows serious knee injuries such as fractures of the bones surrounding the knee or tears in the knee ligaments and tendons that damage the cartilage over time, causing knee pain and limited function

• An injury that didn’t heal right

• Degenerative disease

• Osteonecrosis (avascular necrosis) - when there isn't enough blood supply to the knee joint and associated structures

• Tumor in the knee joint

• Childhood (congenital) knee disorders

More on arthritis in the knee

The knee joint has three “compartments” that can be afflicted with arthritis. Most people have both symptoms and x-ray findings that suggest an involvement of at least two of these compartments; for example, pain on the side of the knee and under the kneecap. People who have arthritis in two, or all three, compartments and decide to get surgery, will most often have total knee arthroplasty (TKA, or total knee replacement).

However, some people have arthritis limited to just one compartment of the knee. They may be candidates for minimally-invasive, partial knee arthroplasty (PKA, or partial knee replacement, or "mini-knee").

Why knee arthroplasty (replacement)?

The primary goal of any orthopedic care is to relieve pain and restore function, to return someone to their active lifestyle. Nonsurgical treatments might be able to accomplish the desired results, though the provider will recommend surgery when other, less invasive methods have been exhausted (medicines, injections, physical therapy, weight loss, and assistive devices).

Knee arthroplasty is usually indicated in cases of severe damage or disease of the knee, whereby these other treatment options have failed to relieve pain and restore function.

Age, health history, other medical conditions, and the status of the knee joint itself also factor into whether knee replacement surgery is appropriate.