I do not have MS (objectively, anyway); but I have had Lhermitte's (or as my last neurologist called it, "Lhermitte's-like symptoms") for the past 14 years. Among numerous other symptoms.
YES, heat triggers it for me--but not so much external temp as exercise. I used to do fast walking, and about 20 minutes into my walk, I'd bend my head to avoid a tree branch, and there it was, regular as clockwork! (I cannot walk more than two blocks continuously anymore, so I no longer get this symptom from exertion.)
But I also get the "Lhermitte's-like symptoms" even in normal temps and without exertion.
When I say "Lhermitte's-like symptoms" I mean an electric buzz, OR a kind of "tense/pulling" sensation or occasionally it will be a vibration when I bend my head down. Over the last 14 years this has occurred in many different places below my waist or in my hands. It will "settle" in one place for days or weeks or occasionally months, then disappear for weeks or months at a time. Always to return in the same place or some new place!
No doctor among the many I saw ever ventured an explanation for this symptom. Except the first neuro, who told me it was MS. Then he said I didn't have MS. No explanations.
I always have Lhermitte's, 24/7. Overheating does intensify the sensation. It happens every time I work out or even go for a non exerting stroll.
thanks so much for replies : ) thanks for the links, JJ. What I am interested in knowing is whether Lhermittes can be brought on by Uhthoff's. Is that your experience, Sarah? Or do you experience them separately?
Here's an example of what I mean. I exercise outside, I get hot, I pick up paper on way into house, bend my neck to read paper as walking along, and there it is, unmistakable tingling up and down spine and into legs.
There are others on the forum who have both.
Alex
I've experienced heat intolerance (Uhthoff's) for many years and as my sx's worsen, so has the negative effect of temperature changes (internal & external) temperatures, though i've not experienced L'hermittes. To be honest I was not sure if overheating could trigger L'hermittes, but MSF does mention 'overheating' so there must be an established connection.....
"Fatigue, overheating, or simply moving the wrong way can cause a flare up of this uncomfortable symptom. If you are experiencing symptoms of Lhermitte’s sign, discuss them with your doctor."
http://www.msfocus.org/article-details.aspx?articleID=331
Cheers..........JJ
added information.......
"In the late 19(th) century, Wilhelm Uhthoff reported on a series of patients with acute optic neuritis who manifested similar recurrent, stereotyped visual symptoms that were of paroxysmal onset, short in duration, and reversible. These 'Uhthoff's phenomena', which are a feature of multiple sclerosis (MS) and other demyelinating diseases, can be triggered by factors including the perimenstrual period, exercise, infection, fever, exposure to high ambient temperatures, and psychological stress."
http://www.ncbi.nlm.nih.gov/pubmed/23732530