Many case studies and clinical observations have suggested that the chiropractic adjustment has an effect on the intrinsic muscles spanning a spinal motion segment.
Previous studies have examined the EMG effects on the extrinsic muscles of the spine and on the peripheral musculature. The present experiments were designed to determine the effects on the intrinsic muscles of the upper thoracic spine as these muscles are segmentally supplied. Subjects will be divided into two groups.
Spinal segments will be designated fixated or non-fixated in accordance with readings taken from a tissue compliance meter. Surface electrodes will be used to establish background/electronic noise. An intramuscular electrode will be inserted into the rotatory muscle of a prone subject and an EMG reading taken. Chiropractic adjustments will be given in accordance with the previous tissue compliance readings and post adjustment EMG readings taken. This study aims to establish an objective analysis of the efficacy of the chiropractic adjustment, on the intrinsic muscles of the upper thoracic spine.
Grant Value: $825
Chief Investigator: Dr Henry Pollard – Macquarie University
Status: Complete
Researcher Update:
- May 1993
Although a pilot, this is an exciting one. The project investigated, by way of needle electromyography of the rotatores of T 1- 4, the effects of a prone thumb technique applied to the contralateral side of the probe. Results demonstrate an adjustment may decrease muscle action potential in both frequency and amplitude. In order for these results to attain significance, this project should ideally attract further funding to improve the number of subjects. We also demonstrated that the rotatore muscle is active in the sitting position, which is in contract to the accepted doctrine.