I have been fighting with my 21 year olds arthritis for about 2 years now. We moved to a new barn 2 days ago and he isn't soar anymore! I am so thrilled that it only took some grass to make the pain stop!
I totally agree with the availability of more room. I don't really believe in stalling for this reason. A muddy pasture could have made him lame as well. If the problem comes back I recommend Cortiflex to help him out.