Your suggestions are very welcomed! I was hoping you would "butt-in-ski", since you're always a wealth of information.
I don't know how they can tell if it's regenerating. Something on the EMG perhaps, or the fact that he has much less pain than before and has regained some muscle mass. I'm sure the pool has had a lot to do with that. I hope serial EMG is not needed, since he was white as a sheet by the time this one was done. The doctor made him lay down for a while to make sure he didn't pass out. It was quite painful, but afterwards he was okay.
Not sure about the pinpointing, etc. either. That may be something to address with ortho. All good questions to ask!
I will find out if the PMR dr. does ultrasound. U of M has the peripheral nerve specialists, but they can't get him in till next year. Something about a really long wait list for second opinion appointments with neurology. I can try again to see if his ortho dr. there can pull some strings to get him in sooner.
Thanks for your input!