Mid-thoracic spinal manipulation appears to have a transient effect on the passive range of motion of the lower extremities

The immediate and 1-week effects of mid-thoracic thrust manipulation on lower extremity passive range of motion.

Authors: 

Derrick Sueki, PT, PhD, DPT, GCPT, Shaun Almaria, PT, DPT, Michael Bender, PT, DPT, and Brian McConnell, PT, DPT

Affiliations:

Department of Physical Therapy, Azusa Pacific University, Azusa, CA, USA; Peak Sports Medicine and Rehabilitation, Phoenix, AZ, USA; Performax Elite, Burbank, CA, USA; dHealthcare Partners, Torrance, CA, USA

"The purpose of this study was to determine whether MTM (thoracic spinal manipulation) would result in a clinically significant change in lower extremity range of motion as measured by the passive straight leg raise (PSLR) test and whether changes would still be present after a 1-week time period. The results of this study did demonstrate that MTM produced an immediate significant and detectable change in PSLR in the subjects who received the manipulative intervention. Subjects who received the sham manipulation did not experience a detectable change in PSLR values. These changes appear transient in nature as after 1 week, no significant change was present.

...The findings of this study appear to reinforce previous studies and suggest that spinal
manipulation has transient effects that extend beyond localized and adjacent tissue responses.
The results of this study reinforce findings suggesting that as an intervention, spinal manipulation can have generalized effects that extend beyond local and adjacent regions to more remote regions of the body. While the physiological mechanisms underlying these effects are still being explored, these results challenge the common perception that the effects of spinal manipulation are due to alterations in biomechanical factors such as improved joint mobility or reduced muscle activity.

...These (and many other results) coupled with De Oliveira et al. (2013), who found that lumbar manipulation increased remote alterations in pain processing, are indicative of a generalized effect to spinal manipulation that may be attributable to  changes in neurophysiological processing".

https://www.tandfonline.com/doi/abs/10.1080/09593985.2018.1492056?journalCode=iptp20