Effect of cervical spinal adjustments on lumbar paraspinal muscle tone: evidence for facilitation of intersegmental tonic neck reflexes.

Objectives: To determine whether spinal adjustments, delivered to the upper vs. lower cervical spine, might result in tonic neck reflex-induced alterations in the activity of the lumbar paraspinal musculature.

Design: Randomized, double-blind, before/after treatment comparisons.

The comparative assessment of paraspinal tissue compliance in asymptomatic female and male subjects in both prone and standing positions.

Segmental bilateral paraspinal tissue compliance measures were obtained from 50 male and 50 female asymptomatic subjects (vertebral segments C7-L5). Interexaminer concordance for the taking of the measure was found to be extremely high (r greater than .90).