First, I have to commend you for stopping drinking. That is fantastic. Not easy to do once alcohol becomes a part of one's life in a big way so am super happy to hear you made this change. We have a forum that supports that too. An I'm always here to talk as an extra ear or friendly person. :>))
Anyway, let me copy and paste this for you: Why does Lhermitte's sign happen?
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There are two main causes of Lhermitte's sign. The first is demyelination, or damage to the myelin around the nerves. The second is hyperexcitability, which is the increased firing of nerve fibers in the brain. Miscommunication between damaged nerve fibers can also cause Lhermitte's sign.
It CAN be caused by a pinched nerve.
Would you be able to see a physical therapist? I did for a pinched nerve myself. The stretching they did released the issue and I was able to get over it that way. ?? It's an option.