According to the authors of this study, as many as 70% of the individuals will experience neck pain at least once in their life, and nearly 60% of these people will continue to report pain 5 years after initial onset of pain. The economic cost of managing both back and neck pain continues to skyrocket, increasing by more than $57 billion between 1996 and 2013.
The authors also refer to prior studies confirming that upper thoracic spine manipulation effectively reduces neck pain and increases neck range of motion. In theory, chronic stiffness in the upper thoracic spine causes compensatory hypermobility of the lower cervical spine, which in turn causes neck pain by irritating joints, ligaments, and muscles surrounding the hypermobile joints. Unfortunately, to date, the majority of research evaluating the connection between neck pain and stiffness in the upper thoracic spine have used manual methods of palpation to identify restricted motion, which have questionable validity.
To objectively determine the connection between neck pain and upper thoracic stiffness, the authors of this study took 9 individuals with chronic neck pain, and 11 who did not have pain, and placed them in an MRI while stabilizing their neck at 90% of their maximum range of neck rotation. The images acquired by the MRI were then imported into a software program to create three-dimensional models that allowed for the precise evaluation of the range of motion present between each segment in the neck and upper thoracic spine. The technique they used had been previously tested and shown to have a high intra-and inter-rater reliability.
Using this highly reliable measuring technique, the authors determined that the neck pain group presented with significant movement restrictions in the upper thoracic spine, with significantly larger ranges of lower cervical rotation than the subjects who presented without pain. There were no statistical differences in rotation between the other spinal levels, and their findings are consistent with a prior 2-year prospective study by Norlander et al. (Scan J Rehab Med, Sep 1997, 29:167) confirming that decreased mobility in the upper thoracic spine is a risk factor for developing neck pain. The findings of this study also explain why so many previous studies have shown that chiropractic manipulation of the cervicothoracic junction is a safe and effective way to manage chronic neck pain.