National Center for Complementary and Alternative Medicine (NCCAM)

NIH…Turning Discovery Into Health®



Timing is Everything in a Column and Segment that Can Buckle

Natcher Conference Center
National Institutes of Health
June 9–10, 2005

David G. Wilder, Ph.D., P.E., C.P.E., Director, Jolt/Vibration/Seating Lab, Senior Research Scientist, Iowa Spine Research Center, Associate Professor, Biomedical & Mechanical Engineering, University of Iowa, Iowa City, Iowa

The health of the spine, a complex mechanism, depends on the successful interaction of a network of active and passive components. Active parts of the network, the muscles, are located on opposite sides of the spine and need to operate in a coordinated fashion to stabilize or move the spine safely. One limitation of our neuromuscular control system is that it takes time to sense the need for muscle action and then call for it. Injury can occur due to rapid uncoordinated muscle action when the spine is exposed to conditions that occur faster than the control system can cope with such as buckling of the spinal motion segment, whole-body vibration, and surprise loads. Understanding these limitations can help in optimizing back treatments and the interaction between people and their environments. Using hands-on demonstrations, the audience will explore a simple six-degree-of-freedom system (a mechanical metaphor for the spinal motion segment) and observe damage to a biological system produced due to a slow and poorly-trained control system.