Hi Bernard, in the absence of a significant injury, the structural lesions reported on MRI could be explained by normal age and activity related changes e.g cuff tendinopathy, partial thickness tearing, degeneration labrum.
This is not an indication for surgery in my opinion.
However, this sort of degenerative changes can in my experience lead to an adhesive capsulitis which may be made worse by being an insulin dependent diabetic.
I am not clear as to what your diagnosis is so difficult to comment.
Additionally, what we know about shoulders that start to show signs of wear and tear is that as time progresses so too does the size and extent of the tears i.e partial tears become full thickness tears and so on.
In my experience, persistent pain and shoulder dysfunction that you cannot live with is usually the number one reason to consider a surgical option not because an MRI says you have some potential age related degenerative changes.
However, if your doctor/surgeon has exhausted all conservative measures (injections and physiotherapy) and completed a thorough shoulder examination (considering MRI findings in light of what he/she sees clinically) and has an operative diagnosis, and you understand what he/she is trying to achieve/fix surgically then I would suggest that you at least consider it.
In my practice, this usually is how we come to have a conversation about surgery, when all other avenues have been exhausted, there is ongoing pain and dysfunction and a clearly defined structural cause (which is sometime difficult in the shoulder).
Finally, you need to get your blood sugar under control, I don't really see it as a contraindication for shoulder surgery unless it is way off the charts, again check with your doctor.
I hope this helps.
Luke
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