Hoof Biomechanics Kwantlen Polytechnic University Farrier Training.
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Transcript of Hoof Biomechanics Kwantlen Polytechnic University Farrier Training.
Kwantlen Polytechnic University
A spring A shock absorber A plastic cone An airbag
The toe – rigid Heel area - distorts Change of shape =
reduction of shock
Pressure = force/unit of area. Pressure increases as the force
increases or the area that the force is acting on decreases.
Example: If the horse gets fatter or the hooves get smaller then the pressure becomes greater.
A lever is a device to facilitate moving an object by creating a torque or turning force
The hoof wall is a lever
When two bodies collide they are in contact for a short period of time
During that time each body exerts a force on the other
Each time the hoof contacts the ground it constitutes an impact
The forces associated cause a shock wave to be transmitted through the hoof and leg
Initial Ground Contact
Ground Contact may be Heel first Flat footed Toe first Lateral side then medial Medial then lateral
Impact sequence of events
Initial impact Rapid deceleration – speed zero Centre of pressure moves from the heels
to the tip of frog area then to the point of breakover
Factors that affect hoof function
Wall length Wall angle Sole thickness Frog size White line thickness Bar size, length and
connection to frog
Moisture content Health of horse Shoes Terrain Speed Weight
The Normal Hoof P.3.
P.3 descends and rotates slightly Pulls the dorsal proximal wall backwards and
down The wings of P.3 push the Collateral
Cartilage outwards, spreading the wall at the quarters
P. 2. and P. 1 rotate backwards around the distal interphalangeal joint (coffin joint)
Insert animation of bone sinking in hoof.
The Collateral Cartilage
Carried back, down and outwards against the hoof wall.
Tension in the ligaments to the surrounding tissue
Expel blood up the leg
Descending bones drive the cushion downwards against the frog.
Frog stay forces the d. cushion sideways Fatty tissue allows distortion Fibrous tissue resists distortion
Blood is squeezed out of the Plexus of the foot
Blood in trapped below the plexus in the palmer area of the foot
The Wall The distal border at the toe is driven
outwards Coronary border at the toe is pulled back
and down The quarters are pushed outwards The heels are pushed back/out
Act as compression springs Resist forwards and backwards
The White Line
The white line is compressed by the sole
The sole flattens Pushes the distal border of the wall out
Spreads sideways and backwards Acts as a soft arch support for the
Review The hoof behaves like a ………..? If the pressure increases on the hoof, the force on the hoof is
increasing or the area of the hoof is decreasing. T/F? The hoof wall is a lever. T/F? Initial ground contact of the hoof may be, heel first, toe first, flat footed,
m/l or l/m. T/F? Which of these does not affect hoof function? Moisture, weight, hoof
colour, speed, terrain. The dorsal wall at the coronary band descends under load. T/F? P.1 and P.2 rotate backwards around the coffin joint. T/F? The collateral cartilage keep the quarters from spreading.T/F? The frog stay plays no part in shock absorbtion. T/F? The blood being driven up the leg acts like a hydraulic damper. T/F? Most of the movement of the hoof is in the toe area. T/F? In a healthy foot the sole should flatten under load. T/F?