Tos can thoracic outlet syndrome go away on its own? how long does it take? or is it something i will have to live with?

No, : No, thoracic outlet syndrome probably will not go away on its own unless you had a specific injury causing inflammation and swelling in that area. But, if you have tos it may be effectively treated with conservative measures such as stretching and physical therapy under the guidance of a trained professional. Sometimes anti-inflammatory injections are used if the condition is felt to be due to inflammation or injury. Approximately 10-15% of the time a decompressive surgery is needed, but this would be the final option after exhausting all other non-surgical interventions.

W physical therapy: It will "go away on it's own if you are a weight lifter (for example) and stop lifting. There are a multitude of causes -- some anatomic, which will not go away on their own and require surgery. However most of us recommend a trial of physical therapy first. This can be highly successful in the absence of an anatomic abnormality. Usually takes about a year of pt to resolve.