Total Disc Replacement Using the SB Charite Artificial Disc

A New Option for Patients Facing Spinal Fusion Surgery

First Seen Live Webcast: Wednesday, January 26, 2005, 4 pm EST (21:00 UTC)

Spine Surgery: The Spine Institute at Beth Israel Medical Center in New York is a Leading Center for Recently FDA Approved Total Disc Replacement

New York, NY- Americans work hard and play hard, and as a result, more than 75 percent of Americans suffer from back pain at some point in their lives. Young people push their bodies at the gym and on the fields and baby boomers are opting to continue being active as they get older. As a result of this trend and emerging medical technology, joint replacement surgeries of the knee and hip have become commonplace, yet many people live with and tolerate back pain. These back pain sufferers now have a revolutionary new treatment option. An emerging type of spinal surgery, called total disc replacement, has shown great promise in clinical trials and has recently gained full FDA approval for a prosthetic disc used in the procedure. Total disc replacement, used for treatment of degenerative disc disease, involves removing the deteriorated disc from between the vertebrae and implanting an artificial disc made of metal and plastic. The SB Charite Artificial Disc was one of the most popular artificial discs among European spinal surgeons, who have been using several of these prosthetic discs on their patients since the 1980s, resulting in pain relief and restored mobility for thousands of patients.

Fabien Bitan, MD, principal investigator for the SB Charite FDA clinical trial at The Spine Institute at Beth Israel Medical Center in Manhattan, took part in the first artificial disc surgery with the current version of the disc in France in 1986. Dr. Bitan became familiarized with this technology during his residency in France during its development stage, and performed dozens of the procedures in France during the '80s and '90s. He has been instrumental in sharing this innovative procedure with his colleagues at the Spine Institute, and in the last four years, he and his fellow surgeons have performed approximately 80 disc replacements during clinical trials, with Dr Bitan performing more cases than any spine surgeon in the Northeast. The Spine Institute of New York at Beth Israel Medical Center was fortunate to be one of the leading FDA investigational sites for this landmark study, and will serve as the training ground for all area spine surgeons who want to learn the technique.

The human spine consists of 33 interlocking bones (vertebrae) separated by shock absorbing bundles of tissue, which can be damaged or degenerate over time. The most common treatment for a degenerative disc is spinal fusion surgery, which involves removing the disc and bridging the adjacent vertebrae with a piece of bone, usually grafted from the patient's own hip. Each year, more than 200,000 spinal fusions are performed. Although fusion is generally effective in eliminating pain, the procedure has its drawbacks. By replacing a flexible disc with hard bone, it creates a section of immobility on that portion of the spine, which can further stress adjacent discs, and this may be the reason that some people experience recurrent back pain years after having surgery.

The SB Charite Artificial Disc is made of a plastic polyethylene core that is sandwiched between two metal endplates that are anchored into adjacent vertebrae. Another artificial disc that currently still in clinical trial testing, the ProDisc, uses the same materials but the SB Charite's core is free floating, held in check by natural spinal pressure, while the ProDisc's core snaps into one of the endplates. Although there are structural and surgical differences between the two discs, both have had excellent results in pain relief.

Artificial disc replacement surgery involves a team of talented surgeons and nurses. A general surgeon accesses the spine by making an incision in the abdomen, below the navel. The surgeon must carefully move the iliac vein to the side to clear the way to the lumbar vertebrae. This portion of the surgery takes about 15 minutes to complete. Next, Dr. Bitan steps in to perform a discectomy to remove the remains of the patient's herniated disc (normal disks are white and a damaged one is usually gray.) To open the vertebral space, Dr. Bitan inserts metal wedges to hold it open and the surgical team uses a test implant to measure the spine for the appropriate prosthesis size (there are 4 different diameters available.) During the entire process, the surgical team uses fluoroscopy, a method of taking continuous low-dose X-rays that appear on a monitor and allow them to see the position of the replacement. The disc endplates are inserted first, and affixed to the vertebrae with a special mallet, followed by insertion of the plastic core. The entire procedure takes less than 2 hours. Patients report immediate relief from the pain and many up are up walking around a few hours after surgery, but most opt to stay a few days in the hospital. Some of Dr. Bitan's patients have gone home the same day. What is most important, and what is not experienced with spinal fusion, is that patients are restored to full spinal mobility, with a normal range of motion.

Not everyone with chronic back pain is a candidate for disc replacement, and the recent FDA approval of the SB Charite disc will not mean and end to spinal fusion. The surgery is not considered appropriate for patients suffering from spinal instabilities such as scoliosis or nerve damage from past surgeries. Patients also need strong, dense bones to hold the end plates in place, which means candidates tend to be younger and more active. "It's not for everyone, but I do think it's the future," says Dr. Bitan. "We're really getting into a new era in spine surgery and it's very exciting."