An orthopedic bed, possibly heated or with a heating pad but I'd be wary of that in case it gets too hot, low sided and placed out of any draft. Pet stairs if necessary. Thank you for caring so much
My little boy is 8 years old and has been 'slowing down.' He wasn't running around 'being bad' anymore (jumping on counters looking for food lol). I did some research and found out a large percentage of cats over the age of 6 have arthritis so I started both of the cats on CBD oil. It's been a week or so and he's doing a lot better. Counter surfing and chasing his sister all day. I haven't taken him to the vet yet because he has to be sedated at all vet appointments, and he has early stage kidney disease so I'm trying to limit the sedation if I can. (He is very aggressive at the vet)
You might also add something else in addition to the heated bed. In winter I like to keep my home cool, because I grew up in the northern part of the USA and like sleeping under blankets. I keep an electric throw in my living room for when I watch TV. I found out, about 1 minute after turning it on, that it is also a very powerful cat magnet. So, when I leave the house when it is cool, I turn on the throw at a low level and leave it spread on the couch. It automatically turns off after ten hours.
I'm not too sure about a heating pad for an arthritic cat. Heat feels good because it loosens stiff muscles but it doesn't help with inflammation of the joints, which is what you are dealing with with arthritis pain. To sooth inflammation you need to use ice packs or something cold to relieve pain due to inflammation. Cold will also stiffen the local tissue, but cold is what relieves the inflammation. Heat makes inflammation worse, but it just feels good in the moment.
FYI, our cat has arthritis too and we take him to a feline veterinary specialist. One of the non-invasive treatments she highly recommended was laser therapy. You should consult with your vet but it may be a beneficial option for your cat. Best of luck!
I bought a heated cat yurt for Gypsy, as she's getting up in years and has some mild arthritis in her right back leg. It also has a microfiber sleeping pad in there. I have arthritis myself, and figure since that's more or less what my doctor suggested for me, it would work for the cat as well.
She loves sleeping in it in the winters, as she's been a California kitty all her life, and thinks 50F is cold. It does seem to take some of the pain away that the cooler weather causes too, since she limps less after hanging out in there. My vet doesn't think Gypsy needs any sort of pain meds or anti-inflammatories yet, I ask every year at checkups because I know how bad arthritis pain is.