Neuro Hack of the week: using TNR's to your advantage

Have you heard of Asymmetrical Tonic Neck Reflexes? 1st described by Magnus and de Kleyn in 1912, when the head is rotated to one side, there is ipsilateral extension of the upper and lower extremity on that side, and flexion of the contralateral (the side AWAY from where you are rotating) upper and lower extremity. Take a few minutes to see the subtleness of the reflex in the picture above. Now think about how this occurs in your clients/patients.  The reflex is everywhere!

This reflex often persists into adulthood and is modulated by both eye movement and muscular activity. When there is neurological compromise, the reflex can be more prevalent, and it appears to arise from the joint mechanoreceptors in the neck and its connection to the reticular formation of the brainstem.

Let’s say you want to improve hip extension on the right:

actively looking with the eyes to the right and rotating the head to the right facilitates the right tricep, quadricep and glute max and facilitates the left bicep, hamstring and iliopsoas
We remember while walking, that the left arm is tied to the right lower extremity neurologically. If you were to rotate your head to the right, you will facilitate extension of the right hip, extension of the right upper extremity (and flexion of the left arm/shoulder and left lower extremity). So, simply put, be like Robocop or the Terminator and rotate your head to the right while your right leg is extending.

Note that the upper extremity is opposite of what we would want to get out of the reflex to take full advantage so you can:

  • do nothing, taking advantage of the lower extremity portion of the reflex. This seems to be fairly effective and is certainly the easiest. This is the way we “normally” walk, and from that perspective, is neurologically sound.
  • uncouple the upper and lower extremity and extend the right upper extremity while the right lower extremity is extending. Uncomfortable and awkward, but effective. Give it a try and see what we mean
  • not swing the arms at all; requires a little practice

Why not try all 3 and see what works best for you and your patient/client?

The Gait Guys. Giving you info you can use in a practical manner, each and every post. Be a gait geek. Spread the word.

Bruijn SM1, Massaad F, Maclellan MJ, Van Gestel L, Ivanenko YP, Duysens J. Are effects of the symmetric and asymmetric tonic neck reflexes still visible in healthy adults?Neurosci Lett. 2013 Nov 27;556:89-92. doi: 10.1016/j.neulet.2013.10.028. Epub 2013 Oct

Le Pellec A1, Maton B. Influence of tonic neck reflexes on the upper limb stretch reflex in man. J Electromyogr Kinesiol. 1996 Jun;6(2):73-82.

Michael D. Ellis, Justin Drogos, Carolina Carmona, Thierry Keller, Julius P. A. Dewal Neck rotation modulates flexion synergy torques, indicating an ipsilateral reticulospinal source for impairment in stroke Journal of NeurophysiologyDec 2012,108(11)3096-3104;DOI: 10.1152/jn.01030.2011