@nanac If the imaging doesn't find a problem, you may want to ask about being evaluated for thoracic outlet syndrome. I have this condition and it can be more common in spine patients who had a spine injury like a whiplash. It is a compression on nerves and vessels that travel under the collar bone to the arms. Having cervical spine surgery causes a lot of inflammation to this area and when I went through it, I had more pain because it affected the TOS. That did resolve in time with my physical therapy, but I still have TOS and can aggravate it with bad posture or doing too much lifting that pulls on my neck. Here is some Mayo information on TOS. It is hard to find a specialist who understands this.
https://www.mayoclinic.org/diseases-conditions/thoracic-outlet-syndrome/symptoms-causes/syc-20353988