In addition to TOS issues, I have to keep my pec major and pec minor muscles stretched. Otherwise, they tighten up so much that they interfere with the circulation in my arms. Well mostly my left side. I have only hints of TOS and pec problems on the right.

Some doctors call it "pec minor syndrome", but whatever, I just call it "tight pec minors".

You can search these forums and the web for various stretches.

Getting this straightened out provided a major improvement for me.

Now if I could get my scalenes fully under control, I would be sitting pretty!