If you have been diagnosed with degenerative disc disease, or DDD, and are experiencing back pain, don’t assume your discs are to blame, says Richard Deyo, MD, Kaiser-Permanente Endowed Professor of Evidence-Based Medicine at Oregon Health and Science University, in Portland.

MRI studies show that almost everyone older than age 60 has degeneration of the discs – pads of jellylike tissue with a hard outer rim that separate and cushion the bones of the spine – but most people don’t have back pain. Therefore, the finding of degenerative discs in someone with back pain could well be coincidental, he says.

At the same time, that doesn’t mean disc degeneration isn’t a source of pain – either directly or indirectly, says David G. Borenstein, MD, clinical professor of medicine, division of rheumatology at the George Washington University Medical Center, and author of Heal Your Back: Your Complete Prescription for Preventing, Treating, and Eliminating Back Pain (M. Evans & Company, 2011).

“There’s a big debate about whether discs are painful on their own or whether it’s the surrounding tissues,” says Dr. Borenstein. “The insides of the discs don’t have nerves, but if they are damaged, nerves can grow into them, so there is a question if they are damaged enough, if that by itself can cause pain.”

What is known is that degenerative discs can play a role in osteoarthritis, or OA, of the lower spine, which is painful, says Dr. Borenstein. In the healthy, young spine, he explains, the discs are like pillows between the vertebrae, cushioning the joints of the spine. But as discs wear out over time, they lose water and flatten and become more like pancakes. The loss of cushioning causes the joints of the spine to become weight-bearing joints, which they were not intended to be, and like all weight-bearing joints, they become susceptible to OA, he says.

In fact, OA is the most common cause of low back pain in people between the ages of 45 to 65. In some people, osteoarthritis of the spine leads to another problem – spinal stenosis, a condition in which the overgrowth of bone leads to narrowing of the spinal canal, compressing nerves. Spinal stenosis usually occurs after age 65.