My doctor told me the tightness is from internal scarring and healing. They really do stretch the muscles wide and the top layer of muscle is cut and when heals can form a thick tight scar internally. The suggestion was to do gentle stretching excersise up to ceiling and side to side..with time it stretches out and hopefully feels better. I have been doing that for the past year and although it is still a little tight sometimes, (I notice it more when I swim laps and have to lift my head back over my shoulder to breathe) I do notice the difference.
Hope you can try that and see how you go.
Hi and WELCOME BACK! I will try to fnd your original question!
I don't have the fullness but I have the tightness you describe after my partial 2yrs ago and my ultrasounds show nothing! It hurts a lot with illness when a gland presses on it. But only the one side .. not the intact side!
Also I had phys. therapy for an ankle problem and could not do many of the exercises cause they strained only that side of the neck!