I had neck surgery  (ACDF) of the C6/C7, swelling occurred on left side of neck after sugery. I had a blood test to check my white cell count, and it was perfect. I was told by my primary physician, and neck surgeon that it was more than likely fluid build up from the surgery. I also need right shoulder surgery  (labrum missing, torn bicep tendon, bone spurs ), and now the right side is swelling.  Physical therapy has not helped. The swelling seems to get larger with increased activities,  and goes away when I sit down. I would really like to know if it really is just fluid.