2019 study looking 1000 people with shoulder pain in the UK found that it is your BELIEF (self-efficacy) that determines if physiotherapy is successful or not. The most important predictor of outcome was the person’s pain and disability at the first appointment. Most of these people still had pain and disability 6 months later.
The surprise finding of the study however, showed those who had high SELF-EFFICACY (expected to completely recover and had confidence in the ability to carry on doing most things despite the shoulder pain) reversed the pain and disability. They even did better than the people who started out with low pain and disability.
The key finding is your level of belief and self-efficacy that you will heal. This is the brain at work. When you believe you will get better, you have a much greater chance of that happening. What this study showed was what I have known for awhile- it is not the physiotherapy that matters, it is the person’s belief in it that matters.