Unicompartmental Arthroplasty

Arthritis of the knee is a painful condition that affects thousands of people as they grow older. But arthritic changes that occur in the knee at a younger age, when patients are in their 40s or 50s, can be especially frustrating. Most often, these younger patients see the medial aspect of the knee wear out before the other areas. This can be very disabling and difficult because these patients are not yet candidates for a tricompartmental total knee replacement.

However, a relatively new version of a well-established operative procedure — “unicompartmental arthroplasty,” involving replacing one compartment of the knee — is providing relief to many patients. Although this procedure has been performed for many years, a new, minimally invasive procedure, offers an important treatment alternative for many patients.

Click here to view a PDF version of a CSO brochure describing Unicompartmental Knee Arthroplasty.

Click here to view information on Synvisc, a therapy for osteoarthritis of the knee.

Follow the links below to find out more.

Defining the New Procedure

The new unicompartmental arthroplasty involves replacing one compartment of the knee which has been worn by osteoarthritis. During the arthroscopic procedure, self-aligning metal and plastic components are inserted into the knee essentially resurfacing the medial compartment and leaving the other relatively normal areas of the knee intact.

The procedure is less painful to the patient and rehabilitation is also more rapid. Approximately 80 percent of the patients treated with this new procedure can leave the hospital the morning after their surgery, and in some cases, the procedure can be done on an out-patient basis.

It is important to note that unicompartmental replacement is a temporary solution for most patients. Wear and tear will continue in the other compartments of the knee and with time, it is possible that these other compartments will also become painful and symptomatic.

However, should primary total knee arthroplasty become necessary, unicompartmental arthroplasty will have little affect on the total joint replacement procedure. The unicompartmental arthroplasty could delay total knee joint replacement five, seven, or even 10 years.

Benefits of the New Unicompartmental Arthroplasty

Unicompartmental arthroplasty offers many benefits to most patients who do not need or are not candidates for total knee joint replacement.

  • Less pain during recovery
  • Quicker rehabilitation
  • Relief from weight-bearing pain
  • Improved balance in the knee
  • Improved knee function
  • Delay or prevent total knee joint replacement

Q & A About Unicompartmental Arthroplasty

Below you will find questions that are often asked about unicompartmental arthroplasty and particularly about the new procedure. Browse through the questions and answers listed below. If you have additional questions or would simply like more information about the benefits of this new procedure, please call (918) 494-AOOK (2665).

You should talk with your physician about the unicompartmental procedure and how it might be beneficial in your particular situation.

Who would benefit most from this type of surgery?

Most of the patients treated are 55 or older. AOOK physicians have treated patients in their earlier 50s, but it is probably not a reasonable option for patients younger than 50.

Some of the symptoms patients may experience include:

  • Pain when standing, switching positions, or walking
  • Persistent swollen knee
  • Locking or giving out of the knee
  • No response from other treatment options

How do you determine if this procedure will help me?

An x-ray taken while you are weight-bearing must show that there is NO joint cartilage in a particular area of your knee.

What types of activities can I expect to be able to do after the surgery?

Because the procedure restores 1/3 of the joint surface, most of the joint remains your own tissue. Therefore, the basic structure of your knee remains the same and the implanted device is not prone to injury. Some of the activities you may be able to perform include golfing, mowing the lawn, and other light labor. It is important to talk with your doctor about any limitations you may have as a result of the surgery.

How long does the prosthetic device usually last?

The functional life of this implant is estimated around 8-10 years, depending on a number of variables including your age, weight, and activity level.

Arthritis of the Knee

Osteoarthritis is a degenerative process in which the cushioning cartilage of the surfaces wears away. It occurs most often as a result of the wear and tear on a joint that occurs with age. When the cushioning of the joint erodes to the underlying bone, the result is pain. In the case of arthritis of the knee, pain is most frequent during weight bearing activities.

Most often, one of the three areas of the knee will take the brunt of the force of everyday activities while the other two areas are usually less affected. It is this most affected area that is treated in unicompartmental arthroplasty.

For information about unicompartmental arthroplasty, please call (918) 494-AOOK (2665).