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Achy Knees? Get Help!

April 10, 2012

 

Seminar Discusses Osteoarthritis and Latest Techniques in Knee Replacement

 

Your knees can ache for a variety of reasons - an acute injury, an infection that causes inflammation and swelling, or physical overexertion that strains the knee. Frequently, though, the cause is chronic osteoarthritis.

"Osteoarthritis, often called 'wear and tear arthritis,' is caused by the breakdown of the cartilage that cushions the ends of the bones in a joint," says orthopedic surgeon Dr. John Dearborn, medical co-director of the Center for Joint Replacement at Washington Hospital. "Osteoarthritis develops most frequently in weight-bearing joints, and it is a very common source of knee pain. We are seeing these problems become more common as our population ages."

Knee pain caused by arthritis often can be relieved by non-surgical treatments such as medications, physical therapy and knee braces. For more severe pain, patients may get short-term relief from injections of cortisone or hyaluronic acids. When there is dramatic loss of cartilage, however, the patient may be a candidate for either partial or total knee replacement.

To help people in the community learn more about osteoarthritis and the latest advances in knee replacement surgery, Washington Hospital is sponsoring a free Health & Wellness seminar featuring Dr. Dearborn and his fellow orthopedic surgeon and medical co-director of the Center for Joint Replacement, Dr. Alexander Sah. The seminar is scheduled for Friday, April 20 from 1 to 3 p.m. in the Conrad E. Anderson, M.D. Auditorium in the Washington West Building at 2500 Mowry Avenue in Fremont.

Total or Partial Knee Replacement?

Dr. Dearborn notes that the choice between partial and total knee replacement depends on the patient's specific needs. "Total knee replacement would generally be performed if the cartilage is badly damaged on both sides of the knee and under the kneecap, or on one side of the knee and under the kneecap," he explains. "Partial replacement would be an option for patients with cartilage damage on only one part of the knee."

Partial knee replacement is a great option for younger patients whose arthritis has not spread throughout the knee, according to Dr. Sah, who completed his fellowship training at Rush Hospital in Chicago where they did a high volume of partial knee replacement surgeries.

"Partial knee replacement also is a good option for elderly patients with other conditions that limit their ability to recover from total knee replacement," says Dr. Sah. "Partial knee replacement is less invasive and preserves bone and ligaments. It also provides better motion and faster recovery, and it often results in a more normal-feeling knee than total knee replacement."

Between them, Dr. Dearborn and Dr. Sah perform approximately 800 total and partial knee replacement procedures each year.

Advances in Knee Replacement Technology

At the seminar, Dr. Dearborn and Dr. Sah will discuss several emerging technologies that hold promise for reducing the time required for knee replacement surgery, minimizing surgical risks and providing more "personalized" knee replacement implants.

"The quality of knee replacement surgery outcomes depends largely on the surgeon's experience and skills, but great technology can make a skilled surgeon even better," says Dr. Dearborn.

"We often use implants produced by Zimmer, one of the most respected companies in the industry, and they have developed a new total knee replacement system that offers a more personalized fit," he adds. "The new sets being tested increase in size in 2-millimeter increments, rather than 4-millimeter increments, so there will be twice as many sizes available. Zimmer has selected our Center for Joint Replacement as one of only 15 sites around the country to receive these sets this month. We will be part of a research study over the next couple of years, studying how often the new sizes are needed."

Another company moving toward providing more personalized knee replacement systems is ConforMIS. "This company recently started producing customized implants for both partial and full knee replacements, using a CT scan to create a 3-D model of the patient's knee to create an implant that conforms to the patient's anatomy," Dr. Sah explains.

"A ConforMIS implant might fit better than a standard-size implant, and it may be more bone-conserving," he says. "Also, fewer instruments are needed to perform the procedure, so there potentially may be a faster recovery. The downside is that these new customized knee implants don't have a long enough track record to definitively evaluate their safety and effectiveness, so we are looking for more data. This is an emerging technology that shows promise and is generating growing interest."

Other technological advances that Dr. Dearborn and Dr. Sah will discuss include:

  • "Patient-specific" measuring tools that use CT or MRI images to create a personalized cutting guide (called a "jig"). This technology may help surgeons more accurately place the pins used for guiding the implant alignment and position.
  • Computerized navigation systems (somewhat similar to GPS) used in conjunction with "markers" placed in the leg to help guide the knee replacement surgery.
  • A computerized system created by MAKO Surgical Corporation that features a robotic "arm" with cutting tools, guided by plans developed from CT scan data. During surgery, a digital tracking system monitors the patient's anatomy, enabling the surgeon to make real-time adjustments to implant positioning and placement.

"None of these new systems is foolproof, so the experience of the surgeon is still crucial," Dr. Sah cautions. "The technology may help minimize surgical risks, but the surgeon still needs to know when to override the system."

To register for the upcoming seminar, or to learn more about the Center for Joint Replacement, visit www.whhs.com.

New Center for Joint Replacement Opens Soon

A new Center for Joint Replacement at 2000 Mowry Avenue, connected to the eastern side of the hospital, is opening in May.

"Our new center brings all our outpatient and surgery facilities under one roof to provide a true continuum of care from the initial appointment through surgery and follow-up care," says Co-Medical Director Dr. John Dearborn. "The facility also houses a new program, the Institute for Joint Restoration, to expand our clinical research. Within the Institute for Joint Restoration, we also intend to develop a charity-care arm of our services that would be funded by contributions."

More than 600,000 knee replacement surgeries are performed in the U.S. each year, and that number is growing. According to report from the Agency for Healthcare Research and Quality, the annual number of knee replacement procedures is estimated to grow by 673%, to 3.48 million, by the year 2030.

"We initially started planning this facility 10 years ago," Dr. Dearborn notes. "Since then, the demand for our program's services increased so dramatically that we added another patient-care floor to the original design. The new Center for Joint Replacement is another example of Washington Hospital's commitment to meeting the healthcare needs of our community."

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