I have the same thing. On my 'bad side', my shoulder is much more forward and slightly raised compared to my other side.

I have often wondered whether Botox in the pec minor would be a good diagnostic tool for me...

What I can't figure out is what caused this?

For one, I battled a left shoulder injury for a year + and recently had surgery in November, so the weakness could be explained by that...and that mess caused the compression.

Or, my anatomy and my predisposal for TOS caused the compression and thus the weakness.

Hell if I know.

Weak core
Mouth breathing
Weak longus colli

The trap muscles are weak.

I do know this much, if the main stabilizers of the scapula (serratus anterior. Lower trap, and Sub Scap ) arent firing properly or you cant seem to get them activated properly and they are a weak as a result of this , the body will over naturally look for other way to move the scaps. It will then start over compensating and start recruiting the Upper trap and Levator scap to move the scapula. This will then cause those upper muscles to be over used and trigger points form in those muscles which can then send referred pain into anywhere all the nerve rout ( arm , shoulder , neck, fingers - anywhere along the nerve route ) and it will slowly "drag" the scaps upwards abnd scapula instability is created, and thats how symptoms and pain are caused.

If the scaps arent moving the way should be , You must re train those neural pathways and start activating the muscles that are "asleep" so to say.

Has anyone looked at the way your scaps are moving ? I know that years of gym work and to much anterior weights and not enough posterior chain work did it for me, I then re trained myself out of that and restored normal function of the scaps. And have been pain free since.

I had a minor flair up a few weeks ago which lasted a month but that was only because i was smashing the gym very vigorously 6 days a week, not stretching and well just getting back into old bad habits. The result of this was TOS type symptoms yet again, and they way i overcame this again was by stopping all the body building type trainings and focusing again on activation of the Serratus , lower trap and the rest of the posterior stabilizers.
3 - 4 weeks of physio mixed with that and i am again pain free. back to normal gym routine.

IF the scaps are the issue, then u must retrain them to work properly again or the symptoms will keep coming back.

If something else is the issue , like a extra rib or ect then i cant help anyone there. All i know i have beat this twice now and the technique that worked was neuro -muscular retraining.

i forgot to mention that tight anterior muscles like the pec minor all contribute to that scap instability, because its essentially playing a "tug of war" with your scaps and the stabilizers and posterior muscles. Then the scalenes get involved and its all down hill from there.
In saying that though once u start correcting this and things start settling back into place it has a flow on affect and you get better alot quicker then you thought.

Hellothere,

I think you are on the money and over the last week I've been heading down this path.

I have first been beating the heck out of pec minor and subclavius muscle to loosen up what's pulling my shoulder forward. Next I've been trying to "awaken" the rhomboids, lower traps, and serratus via the following:

* Scap squeezes -- no weight for 30 seconds, light cable rows with a 3 - 5 second squeeze. Focus is on isometric work vs. pulling a lot of weight.

* Scap pushups and pushup holds -- this is essentially leaning against a table edge and holding the pushup position when down.

* Prone cobras

My symptoms aren't as severe as a week ago. They are still there, but hoping continued focus gets rid of this.

KY

But how to correct it? my pec minor and scalpula are bad. My traps seem worse than my scalenes usually.

can you be specific on exercises to do? Thanks,JKL