I guess it depends on how bad your joint issues are. Most of the work involved in cutting, drilling, squaring and finishing pen blanks are done by tools with jigs that don’t require a lot of pressure from your hands and fingers. Assembly also is done by a press...There can be some torque involved with tightening and loosening chucks to hold drill bits and pen blanks, and the actual turning requires the ability to drip the turning tools securely, but with sharp tools I would say you don’t need too tight a grip. But for some this may be quite difficult. Hopefully not for you.
I like to play guitar a little each day - if I can - and my fingers are stiffer the next day from that activity much more so than any day I’ve spent turning. I like to think both activities are therapeutic! Hope that helps and good luck!
What Timing! Are you talking normal wear and tear or are you adding in the stupid factor? This morning I was grinding some material to help a friend catch up on some orders. I use a bench grinder with an aggressive belt sander attachment on one side. The other side has the standard grinding wheel still mounted on the shaft. As I was reaching for another stick I stuck my thumb in the side with the original wheel and ground through my thumb nail and put a 3/8” hole just under the knuckle. As of now there’s not much pain but I bled like a stuck hog. As of normal use of the hands I haven’t noticed any changes but as far as the other goes it seems like I’m steady learning new stupid stunts. Luckily there not as often but still occur every once in a while.
I agree with Russ. What wear and tear from this hobby?? This has to be such an easy hobby kids do it, seriously. Have to say if you have joint issues than anything you do with your hands will have an ill effect. Good luck with that. But this hobby is not one that will wear you down. Wear the pocket book down but not the body.
I would first start off by saying this... for over all health, take the supplements that are for a good immune system. That will carry over some to your joint issues. Trying to stay of medications, they best thing for joint care is (gulp!) cutting back the carbs. Carbs contribute a lot to joint pain and even gout. You might want to look into the keto type diets.
I think where I feel my issues are handling small parts in assembly more than the turning itself. My day job for decades has involved working with computers so all that typing plus many years of video games, playing piano, playing drums, etc has started to take a toll on the dexterity. I'm still able to work with the small parts but it's not nearly as easy as it used to be.