Study describes how degenerative disc disease could cascade

Sep 15 2011
New research supports previous theories that degenerative disc disease is often the first in a series of events leading to lumbar deterioration and back pain.

The spinal cord is protected by a column consisting of vertebrae, the gel-like discs that cushion the spaces between the bones and the facet joints that connect consecutive bones in the back to allow movement. When it comes to deterioration of the lumbar spine, there have been disagreements among researchers about where the problem begins - in the front of the spine, with the discs, or in the back of the spine with the facet joints.

Researchers in Boston believed that previous studies were problematic in selecting the patients they investigated, especially since some of them came from spine clinics, which could have skewed the results. With this in mind, they decided to analyze the relationship between problems in the front and back of the spine, and used subjects from another experiment that studied heart disease in order to minimize bias in the results, as published Sept. 13 in Biomed Central Musculoskeletal Disorders.

Study authors randomly recruited 361 patients from the Framingham Heart Study, a project that began in 1948 and included three generations of subjects. With the help of radiological images, the researchers examined the patients for facet joint damage and shrinking discs, a sign of degeneration.

Results showed that for the most part, deterioration of the lumbar region begins with the discs in the front of the spine. In general, as subjects got older, it became less likely that they wouldn't have lumbar deterioration, or that damage would be limited to the intervertebral discs. Instead, older subjects had better chances of having degeneration to both sides of their spine.

However, up to 20 percent of subjects did not follow this trend, and instead, lumbar deterioration began with the facet joints. The researchers speculate this may be because these individuals were older or had a higher body mass index, but further research is needed to verify that. Genetics may also influence how the lumbar region deteriorates.

Currently, there are several treatment options to treat back pain related to degenerative disc disease, according to the National Institute of Arthritis and Musculoskeletal and Skin Diseases. This includes spine surgery to either remove discs or insert artificial replacements. A less invasive option is an outpatient treatment known as intradiskal electrothermal therapy, in which wires are inserted into the discs, and an electrical current passes through to strengthen the collagen.