|The higher the heel the harder it would be for the horse to land any other way than toe first.|
The above quote is a bit of an "ah ha!" moment for me. It is pretty obvious that we are all aiming for heel first landings, but leaving too much height in the heels so they are comfortable to land first may be counter-productive. But then if they have weak heels they need a little extra height for comfort and to encourage proper movement. Oy!
HOWEVER I still lower tall heels, but slowly. At a set-up trim, I will take the heels down much less than I think they need to be if the horse has weak digital cushion, frog & lateral cartilages - but I bring the heels back as far as I can. The second trim I will schedule for 1 or 2 weeks (depending on how bad the foot is) after the set up trim, and if I can't get the heels down to where I want them at that time (according to the horse's soundness) then I will come out again in 1 or 2 weeks. If it were my own horse, I would trim them down a millimeter or two every couple of days over the course of a few weeks.
I found it hard at first to see a heel first landing. When a horse is moving slow enough to see it, it is generally at grazing pace and the horse will not land heel first then anyway! The horse has to be marching along in a fast walk or trot. What I find works is not watching the foot - I watch the horse's knee. If it is straight before the hoof hits the ground, then that is a heel first landing. If you aren't sure if it is straight or if it is borderline, then the horse is landing flat. A knee that straightens after the hoof is on the ground is the toe first landing we want to avoid. If the horse is walking in loose dirt or on an arena surface, a toe first landing will produce a little puff of dust out the front of the toe.
Practice on YouTube watching horse videos to develop your eye, that is what I did! There are heaps of slow motion videos on YouTube, like the one above.
Heel first landings are important because, well, everything. Everything will fall into place if the hoof lands heel first, and everything will fall apart when there is a toe first landing. The heels have specialised structures to take the force of the horse's stride - digital cushion, lateral cartilages, the frog and the function of p3 where it becomes ground parallel when loaded. All these structures work correctly when they land first. They develop and become stronger when used.
How to trim for a heel first landing? You need to be able to recognise that individual horse's optimum heel height, address thrush infections, ensure the bars are not too tall, bring the heels back as far as possible. Easy, huh? :P
|Gracie heels before (left) and after trim. Note that the heels are slightly longer due to soft ground at the time. (Heels sink in and frog still gets pressure)|
|Allie before and after trim. Frog a little thrushy, she wan;t landing heel first properly and the frog started to suffer because of it.|
|Gracie right front heels. Note the right heel has an old scar that grows down and affect the heel structure.|
|Bertha - this horse is comfy on her heels and was at 6 weeks at this trim - heels grew long and came forward and uneven. Shorter trim cycle would help prevent this.|
|Bertha heels pre-trim. Frog passive, too much so. Frog starting to get ratty and flaky, not being exfoliated. Perfect environment for thrush which would just make the back of the foot even less able to take proper heel height.|
|I know I keep posting this photo, but it is such a good example of poor contracted heels. (Archie)|
|Same hoof as above, heel view, post trim. Lands heel first in boots or barefoot on soft ground.|
|Archie left hind pre-trim. This leg is recovering from an injury. Unusual for hinds to be so contracted too.|
|Remy - another contracted hoof, deep central sulcus. Sky-high heels. These are obviously two different feet - his two fronts I think. The pic on the fight is his clubby foot.|
|Poor Archie again. Note I have taken the heels down to the level of the frog - this frog needs the stimulation more than the protection, otherwise we will never get out of the contracted-foot circle.|
|Archie set-up trim. Those bars were huge and had thrush all underneath them. They needed to come out and I had confirmation of it as they didn't pop up as severely again.|