Hi Hope -
I read your introduction (in your 1st post) and gosh...your symptoms and history really sound like TOS to me. Are you seeing a doctor who is highly specialized in TOS? I would think that an experienced TOS specialist would diagnosis you on the spot based on your symptoms and history alone.

Otherwise, I wanted to mention, that my doctor told me that if the scalenes are highly scarred, they become almost tendon-like, and the Botox will not provide the chemodenervation and relaxation effect that would otherwise occur in normal muscle. Therefore, Botox will not work in these cases, even though the scalenes are the problem. Given that you've had 5 MVAs, with 4 of them being potential whiplash incidents... perhaps this is why the Botox is not working for you.

Also, I've had an MRI/MRN of the brachial plexus. I have one-sided symptoms and we were "hoping" to find that the anterior scalene muscle had hypertrophied/enlarged on the symptomatic side, compared to the non-symptomatic side. This did not show up on the MRI. Instead, we found that the brachial plexus is exiting the scalene triangle high up (in the narrower part), with the upper trunk particularly high. It's an interesting finding since I tend to show more upper trunk symptoms. However, while such anatomy is thought to be a predisposing factor -- it is far from definitively diagnostic.

IMHO... I think you should go forward w/ the MRI/MRN and also seek a second opinion from another TOS specialist, even if you have to travel to get to one.

Hope this is helpful, and best of luck to you.