Interesting case...
Would you mind to clarify few things for me please?
Is the parasthesia objectifiable? If yes, does involves a nerve distribution or a dermatome?
Is the muscle weakness objectifiable? If yes, which muscle or myotomes?
How are her reflexes?
How is her breathing pattern?
How is her posture?
Has she seen any specialist/physician for that problem? If yes what are their considerations?
Which kind of tests have you performed to say that TOS is positive? And what did you use as positive or negative response? TOS tests may be very unreliable
All the best
Emanuele