Suggestion 4 Supraspinatus/tendonitis/impingement

Years ago I was doing chinups I am about 5'7 so any chinup bar tends to be quite wide.. so I was doing palms forward wide grip chin ups and it felt like something popped in my shoulder... I was used to what kind of felt like the bicep tendon flicking in the groove within some ranges of motion but this was completely different and very sharp 

Hurt like hell for about 2-3 weeks but then got better, with occasional flare-ups..

I couldn't tell exactly where the injury was as it felt like it was in the back in some positions and in the front in others but the pain was deep in side the joint, almost like it was the socket itself.

Laying on my left side and raising my arm out to the side in front of me as well as crossing my right hand across the body to put on the outside of my left shoulder is still painful even years later... at the time I couldn't raise it without sharp pain.

It did get better after a couple weeks though... and rotator cuff exercises and a lot of stretching helped.

about 5 years later I was doing chinups again... same as before.. wide and to the front... and again something popped...  this time it was just a dull ache... not nearly as sharp as before... so laying off it and again more stretching and rotator cuff stuff helped... doctors did an x-ray and said nothing was wrong and that I should go get an MRI if I want... (8+ months wait) so I said screw it and let it go... I didn't have thousands of dolars to pay to jump the line and get a MRI within the week like the pro athletes do

About a year ago I was in a motorcycle accident...  fairly minor injuries and most of it below the waist...  but after being on crutches for 2-3 weeks it flared up again...  this time more of a constand dull ache in the joint...  it gets worse and subsides but I am pretty much feeling it all the time... but it is liveable so far..