Don't think of TOS as a single part in your body. TOS has more to do with vast structures that flow throughout your entire body. This is part of the reason why it is hard to diagnose. [You go to a hand doctor for hand numbness and they are stumped.]

When my physical therapist did manual work to lower my rib, my feet would kick out instinctively. I believe it is because the giant nervous system was gaining slack. My feet probably loaned everything it could to my shoulder. Your entire body gets 'tight' because of stress in one area pulling everything towards it.