I now know why this happened, at least I think so. It is pretty trivial and can be simply explained by sloppy work by farriers and trimmers, who never really bother to look how the horse walks. If someone would have looked carefully they would have recognized that Molly's lateral toe had become long and was hitting the ground before the heels had a chance to land first.
The picture below shows what happens when Molly places her foot on the hoof stand: the leg is crocked, it has a strong tendency to lean inwards. As explained in a recent post this tendency is caused by the fact that the medial side of her P1 is longer that the lateral side (see this entry). Molly can absolutely not extend the leg for it to become straight on the hoof stand, something that Gus has absolutely no problems with. Also, her FL is straight on the hoof stand. But not her FR.
The consequence of that leg anatomy is that the lateral toe area is pretty much out of the trimmers sighting when the hoof is up on the hoof stand. The picture does not show it all that well, but I can tell everyone who doubts what I am saying: the lateral toe is invisible from the trimmers perspective when the trimmer looks down from the top at the hoof on the hoof stand. The trimmer would need to lean down far enough to the height of the hoof to really inspect the growth lines on the lateral toe in order to see them. This was not done, not by my trimmers and most likely not by the hoof care professionals who trimmed Molly before I owned her. This has resulted in the toe never really being trimmed properly along the growth lines and simply becoming long.
|This picture is from today, and Mollys foot is now, finally, after 2 years, balanced|
The picture below shows Molly's hoof in January 2011, when I released my last trimmer from her duty because I no longer wanted to accept the frequent abscesses. In the left picture I have indicated the growth line of Molly's hoof 2 weeks after she had been trimmed last by my professional trimmer. It is obvious that the lateral toe wall was pushed up, indicating a lot of excess hoof wall in this area. This was exactly the area where Molly hit the ground. Also, on the sole, one can see a black hole in the lateral toe. This was a chronic bruise, that was the reason for the frequent abscesses. Moreover, the whole hoof had taken on a weird triangular shape (I now know due to the side bone that developed due to that excess wall pulling on the lateral cartillages in unnatural ways).
Now the problem was that I myself was a total beginner when I started trimming. When I looked at the hoof from the front it looked quite balanced. I always noticed the bulge in the coronary band on the lateral side, but I was told to address it via quarter relief, which I tried. Quarter relief proofed unproductive placing even more pressure on the lateral toe. So the hairline did not come down. What Molly needed was lateral toe relief, actually placing more weight on quarters and heels instead of on the toe.
I realized that relatively early on but I ran in problems: as the sole around that area was constantly inflamed (hard and plastic like, due to the constant hitting of the ground), I almost always, when I tried to lower the wall through the sole, hit blood or wound serum. So I was hesitant but still kept going slowly removing sole and toe wall in the lateral toe. Since watching Gene Ovnicek's videos, I knew at least how I could find the life sole in the quarters. He also has quite good explanations on how one can project that life sole plane forward from the quarters in the toe. So at least since I knew about Gene's method, which was not until very recently, I was pretty confident that the bruises/serum pockets that I had seen in the toe were not actually live corium.
In May 20012, Molly had another abscess (the only one since I started trimming in January 2011) in exactly that lateral toe. It erupted at the coronary band. It grew down until 2 weeks ago, when it had grown down enough that the lateral toe wall underneath broke off (see picture below, orange line indicates where toe wall broke off).
I think that this breaking off of the lateral toe wall gave the hoof the final push towards healing. Molly is now able to get her toe out of the way when she lands and all bruises are gone from that area. The sole is still a bit unusual in its consistency in the lateral toe area, but this is hardly surprising given in was inflamed for probably 6 years running.
Just in the last 2 weeks since this toe wall has broken off, Molly made enormous progress, her hairline is dropping and the foot is getting rounder and rounder. My goal is to revert the side bone! We will see if this is going to be possible. The next x-ray will show.