August 8, 2011

Disc Degeneration

(Ivanhoe Newswire) -- Nearly 80 percent of the population suffers low back pain at some point in their lives. A new study sheds light on the process of spinal disc degeneration.

Using a computational model of the lumbar spine, scientists from the Institute for Bioengineering of Catalonia looked at the effect of external "loading" on two important cell solutes related to disc metabolism: oxygen and lactate.

Degenerative changes are thought to be linked to a failure in the transport of nutrients from the peripheral blood vessels to the discs, which affects solute concentration within the disc and depends on tissue composition and the disc's response to mechanical loads. The scientists say overloading can be damaging, but normal loading allows healthy transportation of nutrients and solutes.

Results of the study showed overloading on already degenerated discs is less damaging than overloading on discs that are still healthy. Researchers also found changes in cell density in discs are important in the process of disc degeneration.

"It's essential for the healthy function of the spine that disc cells are provided with the nutrients necessary for tissue maintenance," Damien Lacroix, head of the Biomechanics and Mechanobiology group which carried out the research, was quoted as saying. "In a healthy disc, we see that sustained mechanical stress -- which alters solute concentration -- affects the transport of nutrients more drastically than in already degenerated ones, suggesting that loading in the healthy disc is important for maintaining proper metabolic balance. It's safe to say that an alteration of cell number caused by this disturbance to the metabolic transport could result in the possible onset of disc degeneration."

SOURCE: PLos Computational Biology, August 8, 2011