There are physios and physios.
In my experience only one out of four has the slightest clue. Here is my 5 point guide (check out the warnings in points 4 and 5 too).
1. Get a solid diagnosis from a competent DOCTOR first.
2. Look for a physio who knows ANATOMY incredibly well. A physio, rather than a physio, will know anatomy better than most GPs. How to check a physio’s anatomical knowledge: 1. ask about the names of the muscles he/she is focusing on and why. 2. ask them the name of the bone or where on the bone a muscle attaches. 3. ask what bursas you should be concerned about. 4. a physio will know the importance of human variation in anatomy, which is much more common than you think. Search your own issue and add “human variation” (glenoid “human variation”). It doesn’t take long to find out if your physio is a “little rusty” on anatomy and if they are, find a physio.
3. Look for a physio who says it’s up to YOU to retrain your posture and/or remould your muscles via a long term exercise program. Plenty say this, but if they lack basic anatomical knowledge OR want to proceed without a solid diagnosis, make sure you exclude them straight away. And make sure you stick to the set of exercises they will give you.
4. BEWARE physios who want to massage you and “fix” you that way. Temporary relief is not what you need and inappropriate massage can be incredibly damaging. I know because one arsehole money grubbing physio failed to send me for proper diagnosis of what turned out to be a very badly ripped shoulder. It took me ten years, lots of pain and lots of recurrent injury on the badly healed and weakened rip to get proper treatment.
The PLACEBO EFFECT is an incredibly powerful and poorly understood thing and you may think your favourite whacko altmed treatment works and your practitioner may even sincerely believe it too (but is more likely just ripping you off). BUT what is probably happening is that your body is naturally healing itself despite your wasted money on anti-science quackery or a bad physio.
As a friend I met online said about his herniated disk: the body can heal itself, it just takes time but the last person who touched you gets the credit.
I’ve had more than the shoulder injury and can speak from lots of experience as runner an athlete.