Engineers develop disc replacement to treat low back pain

Submitted by BRIGHAM YOUNG UNIVERSITY

Special to Feeling Fit

In between the vertebrae of the human spine are 23 Oreo-sized, cartilage-filled discs that hold the vertebrae together and allow for spine movement. While the discs are critical for movement, they can become the source of back pain when they degenerate or herniate.

A new biomedical device to surgically treat chronic back pain -- an artificial spinal disc that duplicates the natural motion of the spine -- has been licensed from Brigham Young University (BYU) to a Utah-based company.

The artificial disc was developed by engineering professors Anton Bowden and Larry Howell and BYU alum Peter Halverson. It will be developed to market by Crocker Spinal Technologies.

The BYU researchers report on the mechanism's ability to facilitate natural spine movement in a study published in a forthcoming issue of the International Journal of Spine Surgery.

"Low back pain has been described as the most severe pain you can experience that won't kill you," said Bowden, a BYU biomechanics and spine expert. "This device has the potential to alleviate that pain and restore the natural motion of the spine -- something current procedures can't replicate."

Currently, the most common surgical treatment for chronic low back pain is spinal fusion surgery. Fusion replaces the degenerative disc with bone in order to fuse the adjacent segments to prevent motion-generated pain.

The solution researched by the BYU team consists of a compliant mechanism that facilitates natural spine movement and is aimed at restoring the function of a healthy spinal disc.

Compliant mechanisms are jointless, elastic structures that use flexibility to create movement. Examples include tweezers, fingernail clippers or a bow-and-arrow. Howell is a leading expert in compliant mechanism research.

"To mimic the response of the spine is very difficult because of the constrained space and the sophistication of the spine and its parts," Howell said. "A compliant mechanism is more human-like, more natural, and the one we've created behaves like a healthy disc."