Accelerations recorded from the spinous processes during spinal manipulative treatments of the thoracic spine.

Abstract

The purpose of this study was to identify the frequency components of accelerations measured on the spinous processes of vertebrae caused by chiropractic treatments, and to speculate as to the origin of the various components. We found distinct acceleration signals in the range of 0-50 Hz and above 200 Hz. The low frequency components were convincingly matched to the displacements caused by the manipulative forces; the high frequency components were found to be similar in duration and shape to confirmed cavitations in synovial joints, thus they were speculated to originate from the spinal facet joints.