I got a produce called “Bute Less”, which helps my 23 year old Arabian gelding. His issues are from going over backwards in the starting gate in his youth. I don’t know how it would help with hocks or legs, but you could look into it. It is better than using bute, which can damage the digestive system if used too often.
Amazon also carries it, and Smartpak may have something comparable.
It is never the horse's fault