Hoof Mechanism - Theory of Hemodynamics

Genetically, the horse thinks they are a wild horse. Parts of the hoof need the right amount of pressure to develop structure. This is why it is so important that foals get to move about and play and not be contained in a stall or small area. Without contact with the earth and movement, their hooves will not develop properly.

Our equine friends need a lot of movement on uneven terrain and side to side flexion to develop the needed structure.

We must look to the research of Robert Bowker, VMD, PhD, and Professor Chris Pollitt – BVSc (Massey) PhD (Qld) regarding the Theory of Hemodynamics (meaning literally "blood movement", is the study of blood flow or the circulation) and how the hoof dissipates energy. We must have good structure in the hoof for hemodynamics to function properly. The hoof functions as a:

  • Spring for storing energy
  • A shock absorbing system for the dissipation of energy (locomotion)
  • Aids in blood circulation within the equine limb

"Heel placement and breakover control the timing of the shut off of blood followed by the disbursement of the blood. Upon loading of the heel, the capsule expands, sucking approximately 1/4 of a cup of blood into the foot. The weight descends onto the sole. The hoof sucks blood into the hoof as impact is beginning.

At peak impact there is a moment in time that the blood can't move. It gets pinched off and pressure builds. At breakover, the horse takes the weight off the sole and all the pressure is released back up the leg. This is a very important part of how movement is helping to circulate the blood. If you don't have a heel first impact and sole pressure, this function is greatly diminished."

During a study in which only the outer wall is weight bearing versus taking that same foot and putting it on foam or pea gravel, it was found that the capillary fill is much greater when there is sole and frog pressure than when a horse is hanging from its hoof walls. And this is merely standing still.

The hoof wall is a big spring that is designed to pull the hoof back together. The force of the horse’s weight causes hoof expansion, but only one thing causes the hoof to snap back making it ready for the next impact, the hoof wall.

To develop lateral cartilages and internal structure, use pea gravel in the turn out areas, ride in boots and pads, trim to encourage a heel first landing.

Weight bearing - the true role of the wall and sole

Contrary to popular belief, the hoof wall should not be the only structure to bear the weight of the horse. This is called peripheral loading and it puts way too much stress on the laminar connection and has a dramatic effect on the blood supply to the hoof. Dr Robert Bowker VMD, PhD recently did research on this and found that on a:

  • correctly trimmed Bare foot: blood flow continues between heartbeats
  • Shod foot: blood stops between heartbeats and blood does not reach small blood vessels.
  • Laminitic foot: blood stops and backs up between heartbeats

Flexible structures in the horse’s hoof expand and contract with each step as weight is transferred from one foot to another.

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The diagrams below show how the hoof should be trimmed (images on right hand side of box) so that both the wall and the sole bear weight.


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No hour of life is wasted that is spent in the saddle.  ~ Winston Churchill