BACKGROUND: Intervertebral discs, which form the cushions between the vertebrae of the spine and make up about a third of the spine’s height, degenerate earlier than any other connective tissue in the body. When a disc degenerates, it loses height and affects the mechanics of the entire spine, possibly negatively affecting surrounding muscles and ligaments. A major cause of back pain, research shows pain from disc degeneration affects 12 to 35 percent of the Western world, according to the journal Arthritis Research & Therapy. “Back pain is common, and the most common source of back pain is a disc,” Michael DePalma, M.D., an interventional spine specialists at VCU Spine Center in Richmond, Va., told Ivanhoe. About 10 percent of back pain sufferers become chronically disabled. When a disc ruptures or bulges to press on a nearby nerve root, the injury is called a herniation. Experts believe some degeneration must take place before a disc herniates.
CAUSES: Aging and injury are the most common causes of disc degeneration. These factors lead to a loss of hydration in the material that makes up a disc, which ultimately leads to the loss of height. This loss of height eventually causes pressure on the nerve roots in the spine, resulting in pain.
New research suggests genes may play a larger role in back pain than once thought. A research team at the University of Alberta recently discovered eight genes linked to degeneration of discs in the lumbar region of the spine. The discovery came a year after the same team demonstrated that disc degeneration is affected in a large way by genetics.
REGENERATING DAMAGED DISCS: While medications, physical therapy and surgery can help some back patients, researchers are exploring new options for treating discs with the body’s own resources. Studies examining treatments like gene therapy, stem cell therapy, cellular scaffolds and growth factor injections are underway in animals, and some in humans.
Growth factors are molecules that bind to cell membranes and activate the growth of new cells. A single injection of the growth factor OP-1 has been shown in animals to both increase the height of a disc and reduce pain, without damaging surrounding tissue. The first trial examining the treatment in humans is underway. “This sort of treatment may find its role in treating the disc before they get to a point beyond which surgery is going to help,” Dr. DePalma said.