While flying over the snow capped mountains of Montana, on my way home from teaching a level 1 dry needling course in Vancouver, BC , I saw lots of folks siting, neck flexed forward in a kyphotic posture, watching movies on their iphones and ipads, or playing a game. It made me think of posture and correct my own while writing this piece. We discussed how sustained muscle contractions at low levels (1) muscle overload and fatigue (2)  low load repetitive tasks and sustained postures (1, 4-5) can all contribute to trgger point formation and chronicity.

Though we did not really discuss it during the weekend, except in a few isolated conversations, I ran across this article (5) while catching up on some reading while on my way home and thought I would share some points (ha! needling joke : ) ) with you.

Though it is a case report and has a sample size of only 2, it is worth making a few points:

This past weekend we talked (extensively) about the pain pathway and its modulation with needling. We spoke of the 3 main physiological mechanisms of how we believe pain and muscle physiology modulation ocur. 1. local responses, 2. segmental responses and 3. cortical or long loop responses.

In short, the local response is secondary to the immediate inflammation of the area needled and the resultant paracrine factors and cytokines causing mast cell degranulation and vasodilation. The segmental reponse probaly represents presynaptic inhibition of the 2nd order neuron in the pain pathway at the cord level from stimulation of IA afferents from muscles and A beta afferents from joint mechanoreceptors. the long loop reponse is probably 2 fold; one activating the decending pain inhibitory pathways from the nucleus raphe magnus and the periaqueductal grey and the other activating the hypothalamic pituitary axis.

This paper (5) talks about the addition of e stim (20 minutes worth) to dry needling. They used a .30 gauge 60mm needle to treat the paraspinals (assumed longissimus) and multifidus muscles at the painul levels, effectively stimulating the segmental PPD at the level of innervation (like we talked about: temporal and spacial summation). They performed intramuscular stimulation (a form of intramuscular therapy) using alligaitor clips to attach to the needles and used a frequency of 1.5 HZ at a level of comfort for the patient (about 4-5/10 on the numerical rating scale). You should note that the paraspinal muscles DID contract at this level. Both patients experinced significant pain relief following treatment.

So, without controls, it is impossible to say if the pain relief immediately post treatment (1st subject) was due to the needling or the estim. The second subject had a follow up a little over 2 weeks later and had lower VAS scores.

Could e stim be a good addition to your treatment regimen, especially in recalcitrant cases (both of these subjects had chronic pain)? The answer is probably.

There are some studies that look at the use of e stim with TPDN (6) with good results. E stim probably works via the segmental pre synaptic inhibition pathway, but could also alter sodium, potassium or calcium conduction at either the nerve or muscular level (7). One cannot deny the potential efffects of long loop reflexes as well from studies on tone and spasticity (8).

I use estim as an adjunt in some moderately acute and chronic cases in my office with positive results. It seems to cause more of an immediate effect (ie analgesia) and improves patient morale (as well as outcomes, we hope!). Perhaps you should consider trying it and seeing of it is a good fit for your practice. It is an unattended modality and is probably benefical to your patients.

1. Dommerholt J. Dry needling-peripheral and central considerations. J Man Manip Ther.  2011;19(4):223-237.

2. Simons DG, Travell JG, Simons LS. Travell and Simmons’ myofascial pain and dysfunction: the trigger

point manual.  Vol 1 Upper half of the body. Baltimore: MD: Lippincott William & Wilkins; 1999.

3. Hoyle JA, Marras WS, Sheedy JE, Hart DE. Effects of postural and visual stressors on myofascial trigger point development and motor unit rotation during computer work. J Electromyogr Kinesiol . 2011;21:41–8.

4 Treaster D, Marras WS, Burr D, Sheedy JE, Hart D. Myofascial trigger point development from visual

and postural stressors during computer work. J Electromyogr Kinesiol . 2006;16:115–24.

5.  Rock J, Rainey C: TREATMENT OF NONSPECIFIC THORACIC SPINE PAIN WITH TRIGGER POINT DRY NEEDLING AND INTRAMUSCULAR ELECTRICAL STIMULATION: A CASE SERIES The International Journal of Sports Physical Therapy | Volume 9, Number 5 | October 2014 | Page 699

6.  Rainey CE. The use of trigger point dry needling and intramuscular electrical stimulation for a subject

with chronic low back pain: a case report. Int J Sports Phys Ther.  2013;8(2):145-161.

7.  Dirk Pette, Gerta Vrbová Adaptation of mammalian skeletal muscle fibers to chronic electrical stimulation Volume 120 of the series Reviews of Physiology, Biochemistry and Pharmacology pp 115-202 21 June 2005

8. Mukherjee A, Chakravarty A.  Spasticity mechanisms - for the clinician.

Front Neurol. 2010 Dec 17;1:149. doi: 10.3389/fneur.2010.00149. eCollection 2010