I understand the functions and the anotomy of the stifle(i just can't spell it right two times in a row)..I understand that by rolling the toe that helps tighten the stifle so it doesn't slip off the joint ..what I am having trouble with is what happened to the leg to let it do that in the first palce..answer in my mind the farrier trimmed his heel shorter than his toe so it loosened the stifle legament so it would not let his leg function properly... with that said..why did it take 10 days for it to happen? Shouldn't it have happened within a day or two?
So the only thing I can really do is to let the foot grow out and start over again leaving the heel alone, just take a couple of swipes with the rasp on the toe every so often..
Rolling the toll doesn't actually tighten the stifle...
As you know--the horse hooks his patella over the inside femoral trochlea and so can keep the stifle from flexing without muscular effort--when the stifle is held fixed by the hooked patella the hock cannot flex--and so the horse can stand with a minimum of muscular exertion. This is what allows a horse to "sleep on his feet"--he can go to sleep without falling down! In order to hook the patella in this fashion the stifle joint must be extended. Horses with straight hindlegs are prone to inadvertant locking--the normal horse has a stifle angle o around 135 degrees; when the stifle is extended 143 to 145 degrees the patella hooks over the inside ridge. A straight legged horse may have a stifle angle closer to 140 and therefore even a very slight misstep may move it the additional few degrees and cause the stifle to 'lock'
Inadequate muscle tone can cause a normal horse to have stifle trouble, and it's even worse if the horse is conformationally prone to locking. Trimming the horse with long toes/short heels adds to the problem because it is changing the angle of the entire leg, plus is putting additional strain on the ligament. The long toes make breakover more difficult, and this in itself puts strain on the ligament.
Quite honestly there is going to be more to proper trimming for your colt t than simply "leaving the heels alone" and "taking a couple of swipes on the toes with a rasp every so often". Heels should still be properly trimmed, as should the toes--making sure that the toes are rolled to ease breakover and reduce strain on the ligament, and making sure that the toes are not long in comparison to the heel. You will want to have him trimmed more frequently--instead of every 7 to 9 weeks that other horses do okay with, this colt may need to be trimmed every 4 to 5 weeks. Maybe every 3 weeks if this is what works to keep him from locking.
I am not really surprised that he is now locking up worse than ever if he was kept stalled for a time & then was turned out & has been racing around bucking, running and playing. After standing around the extra exercise will tire him, and as he tires his muscles will work differently, perhaps transferring extra strain onto the ligaments by allowing his legs to move differently than they do when he is rested--and especially if he has had nothing further done with his feet. Even if there currently isn't enough hoof to allow you to have some taken off the toes I would at least get the toes rolled.
As to why it took 10 days for the problem to show up after trimming...hard to say for sure, it could be a time/stress factor, it just took awhile for the longer toes to cause stress to the ligament, or perhaps he has hit a growth spurt, causing his muscles/ligaments to lengthen too quickly & therefore weakening the ligament that allows his stifle to lock--or a combination of the two...
I maintain that it is very doubtful he has actually injured his stifle, especially if both are now affected--because as I said earlier, a locked stifle would not be the first symptom of a stifle injury. As I said before, there would almost certainly be some heat & swelling in the injured stifle--and as Dr. Taylor said the horse would be standing on his toe, unable to put weight squarely on that foot. When made to walk the leg would probably swing stiffly out to the side in an effort to avoid moving the stifle joint--the leg would be stiff but not actually locked, and the hock would be flexed--not locked in the extended position as it is when the stifle locks up.
