Most tests for TOS will come up normal, unless you have anatomical anomalies, or are so far advanced w/TOS that the damages are severe enough to show on testing.

If you had some sort of acute injury that set off TOS, then depending on what something may show on testing..

If your symptoms aren't constant and are not overly severe - I would focus on finding great PT, DC, bodyworkers and a lot of home care/self care.

If you have triggerpoints , poor posture, muscle spasms, hypertrophic muscles - those can be very painful and cause many symptoms - but won't show up on testing.. those need hands on palpation..