It turns out I was W - R - O - N - G
Within 24 hours there was a ridge developing on the outside of his hoof; and I don't mean a delicate little wavy line. Over the next few days it grew larger and continued further around the side of his hoof towards the front. It also began on the inside of the hoof so that it was working from both sides forward, although that side did not start developing until the third day. He was also very obviously unsound. He didn't even want to go up for grass, instead preferring to stay in the small, flat area at the base of the hill.
Mark was out of town on a working vacation, so I called Dr. A's office to see what their opinion was. At the very least I wanted to get some Bute to make him a little more comfortable. When I explained what Tom was doing and what I was seeing they suggested I come in for new x-rays to make sure there wasn't rotation in the hoof. That was scary to think about, but we made an appointment for the following Monday.
Here are some pictures of the hoof on March 26th, the day of the vet appointment. They are cell phone pictures, so aren't the best quality, and the only thing that you can really see is that there is a ridge developing. I wish I'd thought to put my finger underneath the edge of the ridge so that you could see how far out it had developed, making the hoof look (to me) like it was buckling to the outside from the pressure. But I didn't. So instead you get these crappy third rate photos that make it look like I'm blowing things wayyyy out of proportion.
I admit that I was a wee bit nervous taking Tommy in for his appointment. At that time exactly one week had passed (Monday 19th - Monday 26th) and there had been dramatic changes in the hoof, as well as in Tommy's overall soundness. He was still very lame if he was off the Bute, and didn't have much of an appetite.
The good news is that the x-rays showed no navicular changes or rotation within the hoof, the canker site was still clear; and it turns out that I really was blowing things out of proportion and there was nothing wrong with the hoof developing a ridge. Now Tommy would disagree with that since he's the one that's lame on it, but Murphy's Law reared up and bit me in the ass and Tommy walked into the office pretty well sound. So I did appear to be THAT paranoid horse owner, the kind that makes mountains out of molehills. We all know one. Apparently I am one - ;)
The bad news is that Dr. A used the x-rays to measure and Tommy only has .33" between the bone in the hoof and the ground outside. That's less than the sole on my flip-flops, and we all know how easily we can feel each and every rock in flip-flops. The rest of the bad news is that even though the canker is still gone, the hole in the hoof is still open to soft tissue. There is just no real healing going on to close it up, and that's been with a year of Glanzen GL which is the most power-packed hoof supplement I could find.
Unfortunately we had to have a talk about euthanasia for Tommy. We seem to be running out of options and nothing's really working out. We're not to that point just yet, but it seems to be looming on the horizon.
So we headed back home with some Pergoglyde, and hopeful hearts that it will jump start his immune system or whatever it is that's out of whack, and that hole in his hoof will heal up.