My 16 year old pony has leg problems...?

He's a POA gelding, 16 yrs. old, blind, very very rarely ridden because of his impairment (he's uncomfortable with it), and yet he has something going on in his legs. A few weeks ago I noticed he was limping so I went out and checked his leg for heat. It was his front left leg and there wasn't any heat on it at all. I ran my hand up and down it and then felt for tenderness. He didn't react to my squeezing his leg at all, but I felt some odd squishy-ness in his lower part of his cannon bone. I soaked his leg with cold water to make the slight swelling/squishy-ness go down and it did a few days later and he quit limping. Two days ago I was feeding hay and saw him limping again so I went out to feel his leg. It was his other leg this time and closer to his ankle. Again, it wasn't hot, but it was squishy like there's fluid in it or something. This does sound like wind-galls, but that usually comes from the horse being worked too hard or on hard ground and he never gets worked at all! His feet are a little long, but we're getting the farrier out soon. Do you think this will help much or should I just wait for it to go away? This has never happened to him before and I really want to know what it is! Thanks for you help.