Total Knee Replacement

By John T Dearborn, MD and Alexander Sah, MD
Co-Medical Directors
Institute for Joint Restoration and Research
Washington Hospital Healthcare System

More than 600,000 knee replacement surgeries are performed in the U.S. each year, and that number is growing. According to a report from the Agency for Healthcare Research and Quality, the annual number of knee replacement procedures is estimated to grow by 673 percent, to 3.48 million, by the year 2030. The good news is emerging technologies hold promise for reducing the time required for knee replacement surgery, minimizing surgical risks and providing more "personalized" knee replacement implants.

Traditional Knee Replacement

Traditional knee replacement surgery, in practice since the late 1960s in the United States, has typically utilized an extensive, 8 to 12 inch incision on the front of the knee. The actual size of the incision depends on the size of the patient. The deep portion of the dissection divides one of the quadriceps muscles in the thigh, called the vastus medialis, and requires that the kneecap or patella, be dislocated and flipped over on itself. Although the muscle heals eventually, the trauma which occurs at the time of surgery takes months to resolve.

Minimally Invasive Knee Replacement

A handful of knee replacement specialists in this country have developed specialized techniques and instruments to allow the same operation to be done with a very limited incision and dissection. The skin incision is typically three to five inches in length. More importantly, the muscle in the thigh is left alone and the kneecap is simply shifted to the side. Minimally invasive partial or unicompartmental knee replacement has been performed using similar techniques since the late 1990s.

The advantages of this approach are many, including reduced pain, earlier return of knee motion, and a faster recovery for the patient. The length of stay in the hospital has also been reduced to approximately two days for one knee and three days for two knees. These improvements have also made knee replacement surgery available to many patients with health problems severe enough to preclude the traditional procedure. Because the exposure is less extensive, minimally invasive knee surgery is not applicable to all patients, especially those with very stiff knees or large legs.

Click here to view Knee Anatomy diagram

To gain more knowledge about joint replacement and related therapies, visit www.dearbornassoc.com OR www.SahOrtho.com