The horse’s hoof is a miracle of engineering. The off structures which operate in balance with each other to form the hoof capsule is capable of withstanding huge forces while protecting to the sensitive structures beneath. In this article, Tack and Talk will help you understand more about the hoof, an incredible structure.
The outer structures of the hoof, consist of:
Sole: This is the area inside the white line, not including the barns and frog. The primary function of the sole is to protect the sensitive structures beneath the sole. However, it also provides support, sharing some of the weight of the horse with the hoof wall.
White Line: It is commonly referred as the white line, but this can be misleading not only because it’s yellowish, but also because it is next to the white inner wall of the hoof. A more accurate description of the white line was commonly used in the 1800s described as the Golden Line. The purpose of this Golden Line, is to join the sole to the inner wall of the hoof, and to seal off the border of the pedal bone protecting it from bacterial infiltration. Aiding with traction by creating a shallow crease at the bottom of the hoof which then fills with dirt.
Inner Wall: This is usually white, unlike the outer wall which doesn’t contain any pigment. This is far more pliable than the outer wall due to a higher ration of inter-tubular horn which binds the tubules together. The primary purpose of the outer wall is to store and release energy during the different phases of the stride to help propel the horse. Also, it provides protection from the structures within, regulating moisture ingress and egress. A healthy outer wall will be slightly thicker at the toe and will have no growth rings or cracks.
Bar: This is an extension of the hoof wall which runs along the side of the frog, ending about half way along the frog. The purpose is to control the movement of the back of the hoof, adding strength to the heel area and protecting it from distortion. The bar should have a high ratio of pliable inner wall to ensure it can move correctly as the heel moves.
Angle of the Bar: Also, known as the heel. Designed to receive the initial impact of the horse’s stride, a healthy angle of the bar consists mainly of pliable inner wall, so that it can dissipate excess shock. The Angle of the bar plays a very important role in supporting the weight of the horse and it is very important that it remains correctly balanced.
Collateral Groove: Is the groove that runs along either side of the frog.
Frog: One of the most important, but often neglected structures of the horse’s hoof. It needs to be wide and substantial and made up of a thick, leathery material. An unhealthy frog is open to infection when left untreated can lead to lameness. The frog works in conjunction with the coronary band, the bars and the sole to provide resistance to distortion of the hoof capsule during the stride. Pressure placed upon the frog directly influences the health of the digital cushion above it. The frog allows independent movement at the heels as the horse lands on uneven ground. Also, it plays a part in protecting the sensitive structure beneath, providing traction and assisting in circulation and shock absorption.
Coronary Band: A very tough structure which sits on top of the hoof wall. It has two very important functions. One, it produces the tubules of the outer wall and second it is very strong and acts as a band of support to add strength to the internal hoof structures as the hoof distorts during the stride.
Periople: A protective covering for newly formed hoof wall just below the coronary band. In the early stages, this material is very soft which helps to prevent the coronary band being bruised by shock being transferred upwards through the hoof wall during the weight-bearing phase of the stride.