Let’s preface this with stating that there are different types of electrical stimulation that have different claims as to what magical things they can do. This blog is referencing the normal Inferferential or pre-mod settings that are so commonly used. So don’t email with claims from other waveforms.
Remember when a kid gets hit by a pitch and the parents tell him to rub it? They’re brilliantly, and unknowingly teaching the gate control theory of pain. Here’s a quick overview. The larger nerve fibers that carry non-painful sensations can override the smaller nerve fibers that carry painful stimuli before they get to the spinal cord to be carried to the brain. By stimulating these larger nerve fibers, you can “close the gate” on the smaller pain-carrying nerves, thus decreasing the sensation of pain. Pretty cool trick. E-stim units, when doing interferrential or pre-mod current does the same thing. It overrides painful stimuli by creating its own sensation along those larger nerve fibers.
It’s always astounding and infuriating when, as a Physical Therapist, I do a lot of skilled manual therapy, stretches and exercises designed to increase mobility and decrease pain that are backed up by medical research, and then when the patient comes back to their next appointment, they say “Wow, my pain is so much lower. That E-stim was a miracle!”
I really hope that my facial expression in that moment doesn’t give away the pure disdain in my heart for hearing such an ignorant phrase.
Don’t get me wrong, TENS (Transcutaneous Electric Nerve Stimulation), just another name for this e-stim, can be very helpful with people trying to lower their reliance on pain medication as it is one more safe tool to help lessen pain. There are take home units that are cheap or free based on insurance coverage and the pads are easy for people to apply themselves. Like any other treatment, it’s just important that people have the correct context surrounding the treatment. They need to understand what it does and why it helps so they don’t develop the faulty idea that it’s a miracle cure.
Going back to our original analogy, do we believe that when we tell a kid to rub their ouchie that we are really teaching them to heal themeselves? Nope. Believing that E-stim heals is no different. From now until the day I retire I will continue to re-educate patients on their stray theories like this one.
-Shaun Palmer, PT, DPT, ATC