Regarding back pain, in my case, I have been thinking it is primarily of a mechanical origin. And to go further back to causation, I believe it has to do with decades of overexertion after the time on a daily basis, when my postural, antigravity muscles, were completely fatigued. I believe these did not have the capacity for endurance that they are supposed to have, due the dysfunctional ability of the mitochondria to produce adequate ATP, or something like that.
I think that as I continually pushed my body past my physical limits, the effects were exerted most strongly on my axial skeleton in this way.
In other words, the more fatigued my deep core muscles got, the more I developed dysfunctional motor patterns of using the more superficial muscle layers to push on. In my case, this often involved even transferring the weight of other nearly paralyzed adult individuals, as part of my work, which I needed to continue doing, to maintain two health insurances to pay for medications for another illness.
By the way, I have had ME/CFS since at least 1989, in my early twenties.
Of course after a day or half day of doing that with this illness (undiagnosed) and literally collapsing nce I dragged myself out of my car into the house after work in a fog, I had no energy to search online and find info about this illness, nor to do proper exercise myself, to keep fit, and hence prevent the dreadful hell of back pain and dysfunction I am trying to dig my way out of today.
I came on the forum today to search threads on back pain and perhaps post a poll asking how many others of us experience back pain, specifically PWME/CFS who have been ill over 10, 15, even 20 years, as my hypothesis is that it is then that the long term effects of prolonged decreased postural endurance may be manifest.