I unintentionally avoided surgery for my shoulder injury last year after I was hit by a car. I had a Grade 4 separation, broken coracoid process, torn up everything -- AC, rotator cuff, etc. During pre-op evaluation the anesthesiologist was palpating my trachea and said "Mmmm... I don't like this."
Turns out my Hashimoto's thyroid disease had worsened into cancer, encapsulated inside the calcified thyroid, but so swollen it had deformed and constricted my trachea. I knew I was having trouble swallowing and breathing during hard exertion, but it happened so gradually I hardly noticed, although I had noticed larger pills were getting harder to swallow. By summer last year I could hardly swallow solid food.
I couldn't be intubated so shoulder surgery was delayed until I had thyroid surgery. By the time that was done, my shoulder had healed -- more or less. And it aggravated older injuries from a 2001 car wreck that fractured six vertebrae from my neck to lower back.
But I was still having constant pain and weakness. I was doing some physical therapy at home, but it wasn't helping much. I got back into PT this year with a good therapist and just the last week or so I'm noticing some significant improvements: less pain overall, especially at night; fewer pain relievers; better range of motion and strength off the bike; able to ride longer with less neck and shoulder pain.
The shoulder is a bit deformed and probably always will be. It's too late for surgery to repair the damage from a year ago, but too early for a total shoulder joint replacement. But it's doing better and should continue to improve within reasonable limits.
Last year at this time I would not have anticipated such a long rehab process.