Bone Post

So, do bone fibrils in the cannon bone at speed get pressed together, pulled apart, does any of this matter? I think so. I'd started a detailed consideration of this here:

http://ratherrapid.blogspot.com/2010/04/theories.html

and in answer to the "theories" presented was thinking we might reach some conclusions on actual impact of speed work on bone fibrils by breaking down what actually occurs in the stride. I've done this somewhat in the two prior posts, but what conclusions?

If we did the science possibly we'd trace an individual impulse of force perhaps emanating from the original hoof strike, follow this on up the leg, stop at each point and measure the effect on structures as it goes, consider what occurs when this meets the other forces such as weight coming down from above and muscles pulling through the stride.

In such a process certainly we'd find that the forces generated during speed work affect structures based on what they are, where they are located, and their particular condition at the time of this particular work. Can we make any generalizations?

Initially we could identify those parts of the leg receiving max force compared to those relatively unaffected. E.g. I'd think one point of max force would be the outer parts of the cannon bones that we call the shins. This area possibly is most affected by the weight of the horse and the force of the stride, and in any horse is a significant area of concern.

Other such areas would be the carpal bones of the knees, and certainly the sesamoids. The long pastern bone is another area of concern particularly with regard to forces that twist. The lowercondylar aspect of the cannon bone is a problem merely because trabecular bone in that area is so much weaker by its construction than the hard cortical bone that makes up the rest of the cannon.

But we begin by considering merely two adjoining fibrils. Then two adjoining osteons. Can there be any doubt that the squeeze and release pressures will first push together followed by a bounce back effect on release? In answer--yes, there is "some" doubt because if those fibrils, and, if that structure, is stout enough, it might fail to move at all, and will only go into motion at time it is overborne. With this we may conclude that many of the fibrils, fibril arrays, osteons, and so on will never be affected at all or be minimally effected due to combos of their location and strength!!!

We may also suppose that other fibrils, etc. will be dramatically affect precisely due to their location and structure, and by this we may conclude that those fibrils unaffected or minimally affected are already strong enough, and those with greater affects might be the exact locations where fractures would develop. These vulnerable fibrils are the areas of concern.

Training:

Tues. 6/15: The one redeeming quality about our constant rain--very thick grass--through which we were able to motor this eve despite standing water from 4 days of rain. 90% trot with a few strides of gallop, and stopping to walk occasionally when the horse sank too far into the ground. We went twice around. 4 days of weather has stopped serious training once again, but, at least we were able to get on and do some work!