OP, If your Dad is having a reverse shoulder joint replacement, by all means, have it done.
I had both shoulders replaced the year before last. My rotator cuffs and the smaller bicep tendons were both ripped and bunched up on my lower "bicep bump"
I was frickin miserable. Anytime I would reach over the sink to turn the water on, it hurt bad. I knew I tore my right cuff and never realized my left shoulder was as bad as my right shoulder.
I have had a handful of other ortho type surgeries and I will agree with everyone else here that says PT is the way. How one PT's will dictate how well the surgery turns out.
My wife tore her cuff on her right arm at work and needed it repaired due to pain. My wife had the cuff repair done and she was a hurting puppy. I helped with "home" pt and could tell how painful the repair was. My wife hurt for more than eight weeks and my wife is no sissy. Her recovery was brutal but successful.
I had a reverse shoulder joint replacements done in '23. I was crapping twinkies because my wife and I have divorced and I thought I would be a one armed victim. I wasn't. I was able to drive myselt around a week out from surgery so that was helpful.
I did every second of my PT. Within four weeks of having my bones cut and re-glued back together, I had better ROM before the knife. The huge difference being that so little muscle and tendon work done, I was allowed to start my heavy PT one week after surgery.
At six weeks out, I had full ROM but I was still pretty weak but I could remove and insert my wallet in my rear pants pocket. It doesn't sound very exciting but ask anyone that had shoulder work done, it's pretty amazing. At the same point, my wife was just barely allowed to remove her sling at night.
Two weeks later, I was on the water casting my flyrod. Not bad.
My second replacement went better than my first. I knew what to expect and how to PT already.
If I was seventy two years old and knew about a reverse joint surgery, I would have it done. Both of my surgeries were done "out patient" and the entire procedure takes about two hours, lay in recovery for an hour and home I went! With a driver, of course.
Don't be a pussy, take your pain meds when you are supposed to, keep ice near and do the friggin PT.
No prob Bob!