Question
I'm grateful for your time, whether you have the answer or not...

I've searched and searched but can't figure out how the number scale is interpreted for Surface EMG readings.  I recently started treatment at a cerviogenic headache clinic & they scanned me, gave me a chart with my readings but I don't know what the numbers mean other than some places are worse than others.  For instance at C6 the reading is 79.2 and at the end of the red bar that correlates, 950%.  950% of what? Normal? What is the range for normal?  And what does 79.2 refer to? I hope my question makes sense. Again, thanks for your time & consideration.

Answer
Hi Veronica,

I appreciate the question and I do have some answers for you. I have personally used surface EMG in clinical practice years ago and I found it to be a great tool for showing high tension sites along the spine. Unfortunately, it was very inconsistent and inconclusive beyond that. The percentage difference in supposed to be based on the normal which is set in the computer doing the scanning. The actual number 79.2 is a number system that the computer follows that has nothing to do with anything but it's own calculation. Studies show that surface EMG is not very specific or accurate for diagnostic purpose which is why I mostly used it for spinal screenings to give people an idea of their imbalances along their spine. The true check always come with chiropractic examination and orthopedic examination. In your specific case, it sounds like your headache is a tension headache and you probably have tension across your shoulders and upper back area. Proper adjustment and PT including stretch and mobilization should be done to help alleviate and correct the problem. More importantly, modify your activity and posture at home or work to avoid constant tension headaches as this is the main cause of it. I hope my answer helps you solve your headaches.