I have an older arthritic horse. What are people's opinions on either stabling through winter or rugging up well and leaving out so he can stay mobile?
I would rug up and keep out as much as possible. I'd bring in in bad weather that the horse found tough eg heavy rain, rain over several days, wind and rain, tough conditions underfoot. I'd probably bring in daily even if just for a feed - the horse will make it clear if he doesn't want to go back out (and vice versa!)
TBH I think it depends on the horse and how big your stables are. My old boy is out at night and for some of the day currently, he's much looser in his hocks but he's always keen to come in as he doesn't like the flies even with a good fly rug and mask. He's in at night during the winter and I know he'd be very unhappy left out at night. My stables are big and he can move around and has plenty of room to get up and down, they also have rubber matting and plenty of bedding. I do think your horse will let you know if he's not happy eg if my horse doesn't want to go out he goes to the back of the stable and turns his bum to me, if he wants to go out, he's at the door! Also in winter, I'm more than happy to give him some bute if he's looking stiff and uncomfortable.
I keep my oldie (37) out all year round. Very well rugged in winter of course. He gets very stiff if stood still for any length of time, and sometimes has a battle to get to his feet, outside he is fine but indoors the surface of the floor (concrete) makes it difficult for him.
My mare has arthritis and I find as much turnout as possible is the best thing for her. In summer she gets 24/7 turnout and in winter is out from 7am-6.30pm as we have to bring in. She has Synequin added to her feed in winter and is rugged up to ensure she doesn't get too cold as that makes her worse
I keep my boy who has arthritis in at night during the winter, but out during the day (about 6:30am-6pm) and out 24hrs during summer. He gets lots of hay in different areas & net sizes to make him move. I had to get rubber matting for the floor though and it was trial & error with the bedding to see what works best. He's very good at letting me know what he wants though & I tend to go with that as much as possible. If he wants out he stands at the door, if not he just plants his feet & refuses to move. I tried to do what I thought was the right think last year & turn him out at night, well rugged, with lots of hay & friends, but it took 45 minuets to get
him out when normally it takes less than 5. He really didn't want to go. That being said I have seen some who really thrive living out year round so I think it really depends on the horse & can take a bit of experimenting to see what it is that they're happiest with.
When I had my older boy I brought him in at night in the winter because he wanted to come in! But it was also because I was on clay soil so not great for him to be slipping around in/pulling himself out of it. He would be in well-rugged and with bioflow boots and stable wraps to help minimise any stiffness in the morning x
I keep my girl out 24/7, only bringing in overnight if the weather is very bad as there's no natural shelter or otherwise in her field. She's a 25 year old full TB and copes just fine. If the horse doesn't get too stiff after coming in though (mine doesn't particularly) then I should think stabling would be fine too. But if the horse gets stiff after being in I'd go for as much turnout as possible.
Having owned 4 arthritic oldies over the years I have always kept them out 24/7 as it definitely helps with stiffness. Just rug appropriately and make sure they have shelter. We are lucky in having a barn so if they really, really have to come in (i.e. there's a hurricane) they can still move around.