Hi there... I have a suggestion for you. Seek out a good endocrinologist and have your parathyroid functions checked out.
The parathyroids control calcium and when they malfunction there are all sorts of derangements of muscle functions, spasms and the like.
It may be only a lack of Vit D, or other things up to a tumor on one of them (there are 4).
Too much calcium in the blood and not enough magnesium to balance it can cause rigidity and spasms of muscles. Since you had radiation of your thyroid and the parathyroids are right in the same place, I'd look at this before considering PD.
Here is one article about this:
http://parathyroid.com/parathyroid-symptoms.htm
This link discusses other problems that can result:
http://en.wikipedia.org/wiki/Parathyroid_disease
(including hypoparathyroidism).
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All truths are easy to understand once they are discovered; the point is to discover them.-- Galileo Galilei
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Weezie looking at petunias 8.25.2017
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