Vet call - Part 1

Dr. B came out to see Kaswyn today and evaluate this latest round of "not quite right"ness. I gave him a history of what had been going on recently, and then he spent some time palpating both front legs. Then he did the standard exam including back soreness test, stifle evaluation, and flex tests. Finding nothing, he asked me to tack him up and ride him so he could watch.

Luckily I wore my breeches, and my trainer's mom helped me tack up quickly, so we didn't lose much time. I rode at the walk for a few minutes in both directions, then at the trot. I started the trot to the left, then went right. When I went back left I could definitely feel a difference.

I stopped Kaswyn and said something about it, and Dr. B said "Yeah, I'd say he's about a 1/2 out of 5 lameness. It's just that he's protecting that left front. He's not flexing the left pastern as much as the right because he's trying to keep a bit of weight off of it. So it's not a mechanical thing."

We proceeded to the x-rays. He took a bunch of views of the left front knee, plus I asked him to take a look at the navicular bone on the left front. That bone had a cyst in it, and over a year ago I started him on herb that could possibly reduce the size of the cyst. I was just curious to see if it had changed at all or not.

First, we looked at the navicular x-rays. He measured a 5 mm cyst. He didn't pull up the old films, but I remembered that the cyst was more oblong in shape than the one I saw today. I just looked in my old vet report and the cyst was 6 mm x 4 mm. So it just got a little rounder. Not much of a change at all. Makes me wonder if I should continue with those herbs. Regardless, Dr. B said he did not think the navicular bone was an issue at all.

Then we looked at the knee films. The image below was taken from Wikipedia and will illustrate the parts of the leg that I'm talking about.

**Warning! Boring horse leg anatomy discussion to follow!**



This is a side view of the bones of the lower equine limb. The photo is labeled with the medical names. The common names of the bones in question are -

Third metacarpal = Cannon bone

Second (medial) metacarpal = Inside splint bone.

So there are two splint bones, one each on either side of, and slightly to the rear of, the cannon bone. The knee bones sit on top of the cannon bone and splint bones. The cannon bone bears the majority of the weight, but the splint bones do bear some weight from the knee. The splint bones are attached to the cannon bones with many tiny ligaments down the whole length of the splint bone. It's usually a very tight connection, and it's purpose is to flex slightly outward as the pressure and weight pushes down from the knee onto the cannon bone/splint bone complex.

Kaswyn's old injury was that he had torn the ligamentous attachments between his inside (medial) splint bone as his cannon bone. This was partly due to his conformation, and partly because of the work he'd been doing. Conformationally, since his leg is not perfectly straight and he's a little pigeon toed, his weight doesn't land straight down like it ideally should. He gets a little too much pressure under that inside left knee and it pushes down on the splint bone more than it should. When you add that to increased lateral work at the upper levels of dressage and more intense workouts, you get tearing.

We did shock wave therapy on the old injury, and we got great improvement which resulted in Kaswyn being better than he had been in quite awhile. But then I pushed a little to hard, and we ended up with another injury.

This new injury is similar to the old ligamentous tear, but it's lower down on the splint bone. The old tear looks like it's partially filled in with bone, which is just what we want it to do. If it fills in with bone then the attachments can't flex as much, and thus won't be painful. Dr. B was not surprised to see this new injury.

What to do about it? Dr. B told me I had three options. Before he even told me option #1, he told me that there was no way I would even consider #3, but he was going to tell me anyway because he thought it might be the best solution.

To be continued...