Today's Q&A is about Neurodynamics.
Q: My mentor and original Norwegian training both have stated "stretching" a nerve is not a valid/safe treatment. Why do you recommend this in the context of Neurodynamics?
A: That is a great question that I forget needs to be answered every once in a while to those with that training. Coming from a Paris background myself initially, I was told by a faculty member grading my case report that "you should never stretch a nerve!" She asked if I only used the median nerve test as only a test. I sheepishly stated "yes..." A little white lie. I did use it as a treatment as well, with good effect to help resolve the radiating arm complaints.
The current concept of Neurodynamics takes into account the peripheral nervous system, and the central nervous system. For brevity, and because the CNS is covered A LOT on this blog, we'll just tackle the PNS today.
Starting at the nerve root, there should be excursion within the foramen with spinal and extremity movements. The actual peripheral nerves themselves should slide and glide within the tissues and bones they travel through. This is referred to as "the neural container." The myelin itself is innervated, yes, nerve is innervated, by nervi nervorum. That means it can refer pain, like any other innervated structure.
Studies starting within the last decade (referenced in The Sensitive Nervous System) identified an entity which was coined an "AIGS" or abnormal impulse generating system. The AIGs can generate impulses both proximally and distally from it's location. It is not necessarily the painful site. It is often found under junctional areas like the CT junction, or restricted areas like a pronator teres. Restrictions to nerve sliding/gliding can wear the myelin sheath, which then causes extra ion channels to form. These ion channels are mechanosensitive, chemosensitive, and temperature sensitive.
- "inflammatory soup" from acute injury
Some or all of these can cause an AIGs to fire. This is a newer concept and takes into account the movement of all the tissues/joints that surround the nerve. It replaces the "double crush."
Tests like the Neurodynamic movements for the upper and lower body have bias for particular peripheral nerves using their sensitizing components. These are based on the anatomical path of the nerve and may include cervical and lumbar movements (or both as in slump testing). These tests can be used as assessments only for restrictions, or as treatments.
Since I currently do IASTM and functional release to the neural container, I find pre and post testing of Neurodynamic mobility often results in rapid changes to what was previously very restricted. I then give the neurodyanamic tensioner or slider as a HEP for the patient to maintain the new stretch/movement tolerance gained with treatment.
If you are so inclined to use them as treatments, i.e. if the patient does not tolerate STM or JM or either are contraindicated, you should use MDT rules for patient response. It is ok if a treatment increases complaints, which in this case is common, even peripheralization, as long as it does not remain worse. Butler himself says he loves paraesthesia! It's his nervous system reminding him he's alive! Our nervous system within our CT and joints is supposed to move fluidly, and we are just using these sensitizing maneuvers to restore that natural motion. You can be very creative with the neurodynamics and oscillate at any joint, or combine treatments and use STM in neural load, or JM in neural load. These are demonstrated in some of my videos.
I hope this helps those of you with Norwegian or New Zealand based training who learned "never" to stretch a nerve. To me, that is like saying you should never extend a lumbar spine, never do a thrust manipulation, or not bother working on innert tissues like fascia. They all have there place in a OMPT toolbox.