Health question.. rotator cuff?

Something I never heard of before about 15 years ago. Seems real common now a days.
I have been having trouble with my right shoulder, and in talking to my daughter in law nurse and my wife's cousin (who is a PA) as soon as I described the issues that was the first thing both of them said.
I did go to the chiropractor a bit between turkey day and Christmas, about 8 visits ( she never mentioned any specific issues) and it dulled the intensity, but I think it hurts more often now.than then, though. Pretty steady dull pain, if I move " just" wrong (right?) It's like someone stabbed a voodoo doll of me in the upper arm, pain gets real intense for a few minutes.

Who knows what about this problem? I'm 55, been a mechanic all my life, most I know who have had this issue have been in a accident, fell on it, etc but I didn't "do" anything like that. It just started hurting one day. Laying on a creeper and putting my arm over my head even with nothing in my hand(weight) like when I roll under to do a DOT inspection on a truck really nails it. Or I reach out to grab the cat, when I draw my arms back in towards my body sometimes seta it off.


Back about 32 years ago I had pain like you described in my right shoulder. It would feel like I’m getting shocked at times. If I was in the passenger seat and had my arm on the open window when I went to move it I had to take my other arm to lift it. Cortisone shots did nothing. A local lady doctor said she could fix it but being a Millwright and the sledgehammer work we did daily it would need done again at a later date. She called it an impingement and cleaned calcium like junk out of my shoulder. It’s been GREAT ever since. She said that junk was tearing at my tendons and muscles.