Once the damage is done, short of replacement surgery, it can't be improved other than be magining any pain and swelling. Taking advice from a physiotherapist can be useful, not only for joints but for posture, i.e. when ironing and we need to remember to bend knees (that don't creak

) instead of bending from the hips to protect the back. Wearing appropriate foot wear is very important too.
I note that DH is beginning to lean forwards and I see it in myself when I glimpse that old lady in shop windows: before realising it's me!
X-ray is usually the first step to take

after which decisions can be made as to future management. I have been SO lucky, apart from RLS and occasional sciatica which reminds me to bend correctly, my joints have worn well. I danced 2/3 times weekly until I was 18 but cycled everywhere, which I think kept the quads muscles firmed up. Certainly when walking/cycling/climbing slopes it's the thighs that HURT! (note to self

)