I had a similar pain my shoulder as described in your original post. I did the cortisone injection with no relief and PT, also with no relief. I had x-rays and MRIs, which revealed an impingement. I was referred to an orthopedic surgeon for a procedure called sub-acromial decompression/distal clavicle excision, which is an arthroscopic procedure. Having received no relief from conservative treatments, I elected to have the surgery.
The surgeons shaved the underside of the acromion, cleaned out some fraying of the posterior labrum, and cleaned out the inflamed bursa.
I am now three days post-op. My shoulder a littlel sore, but I'm actually moving it around pretty good. The doctors expect I can get back on court for light rallying in two weeks, and back to serving in about a month. Best of all, the pain I had is expected to be gone...permanently.
I'd recommend considering the SAD/DCE surgery if ALL conservative methods fail. Assuming you can go without tennis for a few weeks, it may be a viable, long-term solution to get rid of your shoulder pain.
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