Sounds a lot like me, 2 torn rotator cuffs, hip bursitis, plantar fasciitis not to mention my back issues....and terribly itchy abdomen, later legs.

I have autoimmune autonomic ganglionopathy. Fascial tissue is highly innervated by the small nerve fibers. They used to say that fascia had no innervation, well, they were wrong.

I am going to assume you don't have psoriasis, because that inflames all the soft tissue.

You can get a skin biopsy for nerve fiber density and an autonomic battery of tests, but for me, absolutely, the connective tissues are heavily involved. (I do have a positive ANA, however.)