ASSESSING TISSUE RESPONSE TO HIGH-VELOCITY THRUST MANIPULATIONS: MEASURING LASTING CHANGES IN C5-C6 FACET JOINT CAPSULE LENGTH WITH MUSCULOSKELETAL ULTRASOUND AND STIFFNESS WITH ELASTOGRAPHY

This study is a quasi-experimental study collected quantitative data , with a pre-test-post-test design. Pre-intervention, baseline measurements of C5-C6 right facet joint length and width with the head of the treatment plinth downward at 45 and 90 degrees, (relative to the rest of the table) and stiffness at 90 degrees, were taken prior to applying the long-axis thrust manipulation. Post-intervention measures were taken immediately after a long axis thrust manipulation of C5-C6 and again at 24-hours after the manipulation. The baseline pre-intervention measures were then compared to the post-intervention measurements. The investigator performing the manipulation was blinded to the quantitative measurements of the ultrasound images. The ultrasound operator was blinded to the outcome of the manipulation.

Inclusion Criteria: * Healthy individuals between 18-35 without neck pain and able to to read and understand English Exclusion Criteria: * autoimmune disease, down syndrome, fusion, fracture, spinal cord compression, vascular pathology, cancer, and/or any other conditions that induce severe instability, inflammation, or weakened bone.