It might be best to seek out a very good PT or DC to evaluate what would be best for you.
Ram rod military posture often is too straight & tense.
If your C ribs are a fairly large /complete set at some point you might need to look into surgery ( with an expert surgeon for best results)

You would probably know if you get a clot, major swelling , hot, painful.
https://www.google.com/search?q=clot...#q=blood+clots