It could be just a knot.
This is my opinion. keep in mind I went to doctor regarding stiff back and the conclusion was this:
if your back is stiff as a plank and you have trouble breathing when you move it may be your Psoa muscles. (the rear muscles work to hard to compensate and viola...a knot! (i had the same symptoms)When the psoa muscles are tight you have to do the stretches and it will work. lay down on your back with but on end of table. bring up one leg to chest and have somebody gently push down on the other leg until you feel them stretch. do both sides. also, use a softball and roll it into you stomach area just above hip.(i thought it was a crock of shit until i tried) A massage therapist would ram fingers deep into that area to massage the psoa muscles and it hurts like a son of a bitch.
do a video search on this..you'll see what i mean. hope this helps.
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