Posted by Anne (Tree) Coley on July 18, 2003 at 22:05:09:
In Reply to: Re: Rapid Heel Growth in Foundered Horses - Tree posted by Gary on July 18, 2003 at 16:06:53:
: : : Hi Jan,
: : : Since no one else commented that rapid heel growth in foundered horses is caused by inflammation I'll just assume it's accepted.
: : : However, not all foundered horses will end up with high heels so it seems to me the rapid heel growth must come from something else.
: : : Think about this, horses with heel pain can actually alter how they use themselves in order to place less weight onto their heels and more onto the toes. When they do this they will compress the toe walls more. With less weight placed onto the heels there's less resistence to them and they appear to grow more quickly.<<
: : I agree with that. However, my laminitic horse has always had dramatic (way more than what would be considered normal)heel first landings at the trot and canter. I never knew why she did this. I have to think now she was trying avoid putting weight on her toes. She also has never responded to hoof testers at the heels. Still, she grew rapid heels despite favoring the heels for weight bearing. Maybe because this area was getting more circulation? Don't know.
: : : Dr. Pollitt's Hoof Studies video proved that when heels were raised this altered the blood flow into the hoof. Less blood could enter in the heel regions so more entered into the toe regions under those circumstances. So therefore, to say there's inflammation in the heels of a foundered horse with steep/high heels would be incorrect. There would actually be more room for increased blood flow to the toe regions particularly in the areas where the bone has lost its laminar connections.<<
: : Yes, increased blood flow, but is that flow competent, i.e., flowing through intact vessels? I've read somewhere that some experts believe blood vessels can burst during acute laminitis episodes from increased pressure (which is felt through strong, rapid pulses). So, while there is a lot of blood flowing into the hoof, it is not always available to the cells in a normal way.
: :
: : : I would suspect that these types of founder cases started with heel pain problems which went unnoticed until the laminitis set in. It's quite likely these horses has heel pain which in turn caused them to shift their weight forward onto the toes, stress the toe laminar connections and start a vicious cycle which ended with laminitis/founder.
: : : So why would a foundered horse of this sort still want to weight its toes and not the heels? Well consider the treatments being applied to them. It's quite likely their heels are now being raised on purpose to relieve the tensions to the coffin bone via the DDFT. It's not a choice any more that the horse places more weight onto the toes because it's now set-up to do so.
: : : Do I think the rapid heel growth was a protective measure. It depends on how you define protective and what it's seeking to protect. I think it's more of an avoidence action vs protective. If this sort of horse had heel pain first, it was trying to 'protect' itself from pain. Or, it was seeking to avoid pain. If a horse owner recognized the early signs and had someone take care of this, via trimming to remove the causes of the pain, the horse would've returned to its natural posture, placing more weight onto the heels where it belongs.<<
: : Lowering my horse's heels through frequent trimming and backing up the toes did not prevent her heels from growing overly fast. See above.
: : : I used to wonder why some foundered horses hooves would grow such an excessive amount of heel. It would make sense to me that heel pain pre-existed the laminitis/founder. It's makes more sense that the raised heels does more to weaken the laminar connections in the toe regions. It makes more sense that the horse is now 'setup' for laminitis and if the right trigger comes along, founder.<<
: : I believe if an intial laminitis episode is severe enough to cause significant rotation and this is not corrected through special shoeing/trimming, the laminae don't heal normally and the horse will always be at high risk for it to happen again. Each episode causes further "scar tissue" and decreased laminar integrity which is permanent.
: : : The other sort of founder cases would be the sinkers where all laminar connections were lost and the coffin bone came to rest on the sole. Those types don't tend to grow excessive amounts of heel. Their feet tend to platter or pancake...just go flat.<<
: : Agreed. And most sinkers don't seem to recover.
: : Jan
: We have quite a few horse's founder every spring here in E. Tex. and I never have seen one want to stand on his toe's? They all assume the standard spread out in front to get off their toes and of course they have their back ends up under themselves to get off their front end. Are you saying laminitis makes them stand on their toes and grow more heel and founder or sinkers want to be on their heels?? Just trying to understand what you are saying about the extra heel growth. Again ,here on all of my cases the whole hoof grows during the acute stage then the toe area slows as the coffin has rotated and then the heels are growing more. Gary
Gary,
Yes, I'm saying that with some foundered horse cases, the horses are avoiding placing as much weight onto their heels and this allows the heels to grow at an increased rate.
You may not see any air underneath their heels while they do it but the fact that they rock back over their hinds will help to shift weight off their fronts. Then you can also look down the fronts of those legs to see what the extensor tendons are doing. You also have to consider the amount of heel these horses are already standing on and how much is maintained. Are their hair lines lower in the heels or high enough to be horizontal to the ground?
The toe walking types tend to be the long-term chronic founder cases. I mentioned a pony I've adopted with 50% coffin bone loss in both fronts. She will toe walk, round her back to get her hinds way underneath her. After a trim she will stretch her stance so that her fronts are well out in front of her but the hinds will be stretched out behind her rather than underneath like when she walks.
Tree