In my research, some neurosurgeons do scalenectomy only.

The history on this is surgeons only did one or the other until the early 90s. Dr. Atasoy (who I think just retired at the age of 80 something) was the first to do both at the same time and the better surgeons have learned to do both over the last 15 years. I actually saw Atasoy and he was the first to diagnose me positive TOS. He offered to do scalenectomy and not rib. I did not understand why so I dug into it a bit and found out he could no longer do both. His nurse actually told me this. I was already looking for a surgeon who was younger but this really sealed it for me to find a younger surgeon. However I do think Atasoy was a pioneer and one of the most knowledgeable in the world of TOS.

I had scalenes and rib removed and I am actually regretting the scalenes. I may be unfairly blaming it on the scalene part of the surgery but it tore my neck up and it feels permanent. I had three previous surgeries on the cervical spine and I think this was just too much in one area and now I have severe scar tissue.

We are all different though. If a doctor can confirm scalenes as the problem it would be an easier operation than the rib.