New option for treatment of lower back pain

Sep 28 2005

Abbott today announced that it has started enrolling patients in a new U.S. clinical study to evaluate the potential benefits of its Wallis Mechanical Normalization System, a new spinal implant technology for the treatment of mild to moderate degenerative disc disease designed to stabilize the spine and reduce pain while preserving range of motion.

The first study of its kind in the United States, this multi-center, randomized trial will compare degenerative disc disease patients who receive the Wallis implant to those who are treated using conservative, non-surgical methods of back pain management. The first surgical procedures to implant the Wallis device took place last week in Eugene, Ore. and Baltimore, Md.

"A very large number of adults in their 20's to 60's suffer from lower back pain, but their degenerative disc disease hasn't yet progressed to the point they require spinal fusion surgery," said Paul McAfee, M.D., of Orthopaedic Associates in Towson, Md.

Dr. McAfee is lead investigator on the trial and one of the first physicians to perform the procedure in the United States. "This study should provide valuable answers to help assess the role that dynamic stabilization devices could play in treating patients' pain," McAfee said.

The Wallis system has been in use in Europe for more than 15 years. It was developed by physicians in France and first used to treat degenerative disc disease in the 1980's. Since then, it has been used in thousands of patients outside the United States.

Americans spend at least $50 billion each year on low back pain, according to the National Institutes of Health. Back pain is the most common cause of disability in the United States and a leading contributor to missed workdays. While most instances of low back pain go away on their own, others may be associated with chronic conditions, including disc degeneration. Currently, physicians rely on a variety of non-surgical techniques to treat milder forms of degenerative disc disease, while advanced cases of disc degeneration are treated with spinal fusion, effectively immobilizing sections of the spine, or total disc replacement.

As the spine's spongy discs or "shock absorbers" deteriorate, parts of the framework of the spine can make contact with each other, causing lower back pain. With the Wallis system, a spacer is inserted between the vertebrae, held into place with stabilizing bands that are wrapped around the bones on the back of the vertebrae.

Because the Wallis device stabilizes, rather than fuses, the spine, it is designed to allow patients to maintain relatively normal mobility at the affected portion of the spine. Also, because the system does not require much bone to be removed and is not attached to the bone with screws or other fasteners, it is intended to preserve the anatomy of the spine to allow for future surgical options if necessary.

Compared to total disc replacement or fusion, the procedure to implant Wallis is designed to be less invasive. The Wallis system is implanted through the patient's back and placed relatively close to the skin, so it doesn't involve cutting much muscle tissue. It does not go through the abdominal area, as is the case for an artificial disc. With less invasive surgical procedures, patients may be able to resume normal activities after a much shorter recovery period.

"Patients and physicians need options to address early to moderate stage disc degeneration," said David Hooper, Ph.D., divisional vice president, Emerging Technologies, Abbott Spine. "Currently, many of these patients find themselves in a holding pattern, in limbo between prolonged, marginally effective conservative care and major surgical intervention. Our hope is that the Wallis device will provide relief to those patients and stop them from progressing toward total disc replacement or fusion."