Total Knee Replacement

  07 December, 2015

The first step when making the decision about knee replacement is to meet with your surgeon to see if you are a candidate for total knee arthroplasty (TKA). Your surgeon will take your medical history, perform a physical examination, and X-ray your knee. Even if the pain is significant, and the X-rays show advanced arthritis of the joint, the first line of treatment is nearly always non-operative. This includes weight loss if appropriate, an exercise regimen, medication, injections, or bracing. If the symptoms persist despite these measures, then you could consider TKA.

The decision to move forward with surgery is not always straight forward and usually involves a thoughtful conversation with yourself, your loved ones, and ultimately your surgeon. The final decision rests on you based on the pain and disability from the arthritis influencing your quality of life and daily activities. Those who decide to proceed with surgery commonly report that their symptoms keep them from participating in activities that are important to them like walking, taking stairs, working, sleeping, etc.), and that non-operative treatments have failed.
 

These are some of the frequently asked questions regarding total knee replacement (TKR):

How long does a TKR last?

A common reply to this question is that total joint replacement lasts 15-20 years. A more accurate way to think about longevity is via the annual failure rates. Most current data suggests that both hip and knee replacements have an annual failure rate between 0.5-1.0%. This means that if you have your total joint replaced today, you have a 90-95% chance that your joint will last 10 years, and a 80-85% that it will last 20 years. With improvements in technology, these numbers may improve.
 

What types of implants are there?

The orthopaedic implant industry has developed a number of innovative technologies in an effort to improve the outcomes of TJA. In recent years, these technologies have been marketed directly to patients, which has increased the awareness as well as confusion on what these different designs mean. The most important message is that while a certain manufacturer may claim that their design is better, almost all of the available registry data (large collections of data from countries that track TJA) show that there is no clear advantage to any of these designs when it comes to improving outcomes. Here are specific implant design terms:

  • • Gender specific: This refers to a modified implant design that accounts for average anatomic differences between men’s and women’s knees. Most manufacturers have incorporated similar modifications in their newer designs, which allow for more sizing options so that the prosthesis can be more accurately fit to the patient’s native anatomy and recreate the natural function of the knee.
     
  • • Rotating platform: This refers to a plastic bearing that independently rotates on a metal tray on which it is seated. More often, the plastic bearing locks into the metal tray – referred to as a “fixed bearing.” Some theoretical advantages to the rotating platform concept when it was initially designed was that it could reduce the wear of the plastic bearing, reduce the rate of loosening of the metal parts, and better replicate how a patient’s knee works (kinematics). Most current data shows that after 5-10 years in use, there does not appear to be any difference between rotating platform and fixed bearing designs in any of these outcomes.

 

Will I need to stay in the hospital?

On average, patients spend one to two nights in the hospital following surgery. Some patients may spend as little as one night, others may stay as long as three nights.

Will I be able to walk after surgery?

Most patients use a walker or crutches after surgery but often will be able to progress rapidly to using a cane.

Can I go directly home from the hospital?

Many patients are able to leave the hospital and go directly home after surgery. It is important to identify a family member or friend who will be able to help with common household tasks such as preparing meals and doing dishes. Some patients will require a stay a specialized care facility such as a nursing home or rehab hospital.

Will I be able climb stairs when I leave the hospital?

In general, patients are able to climb stairs after leaving the hospital; however, it is often initially slow and tiring. This soon improves, but most patients are happiest if initially they are able to stay on one floor after returning home from surgery.

Will I be able to drive immediately after surgery?

Most patients are not safe to drive for the first three to six weeks after surgery. Your surgeon and their team will guide you as to when it is safe to drive.

How long will I be out of work after surgery?

Most patients are out of work for at least a few weeks following surgery. Patients with very physical jobs may take as long as three months to return to work.

Will I have to take pain medication after surgery?

Many efforts are ongoing to reduce the pain patients have after surgery; however, most patients still do require some pain medications for the first few weeks after surgery.

Will I need Physical Therapy after surgery?

All patients benefit from specific exercises after surgery. These will be directed by your surgeon and often will involve a physical therapist. Most patients need to do their exercises for a minimum of four to six weeks following surgery.

How much will my joint replacement weigh?

They weigh between one and two pounds.

Are there any activities I will not be able to participate in after I recover from my joint replacement?

In general, most patients are advised to avoid running, jumping, or impact sports after surgery. It is hoped that these recommendations will make your joint replacement last longer.

Encino Office

Shahin S. Rad. M.D.

16311 Ventura Boulevard
Suite 1150
Encino, California 91436

818 477 0787

Marina Del Rey Office

Shahin S. Rad. M.D.

13160 Mindanao Way
Suite 300
Marina Del Rey, California 90292

310 246 9494