Structure of the Foot

The foot can be divided into three areas - the toe, the quarters, and the heel, although no natural division exists. The wall is the part of the hoof that can be seen when the horse is standing, and bears most of the horse's weight.

The wall is made up of insensitive horn which turns inward at the heels to form the bars; the bars can be seen on the ground surface of the foot and look like hard ridges between the frog and sole. The fact that the wall does not form a complete circle allows for expansion of the foot as it hits the ground during movement.

The outside of the wall will often appear to have small ridges running horizontal to the coronet band, which are referred to as growth rings. The horn grows downward from the coronet band, and is made up of thousands of tubules, which are cemented together by intertubular horn.

The wall is covered by a thin protective membrane called the periople, the main function of which is to protect the area where the coronet band meets with the hoof wall.

The periople will naturally wear away on the lower half of the wall, and therefore only plays a minor role in reducing evaporation of moisture from this area. The ground surface of the foot is largely made up by the sole, which should be concave to the ground, the white line which runs between the edge of the sole and the wall, and the frog, which acts as a shock absorber and antislip agent.

The frog is elastic, wedge-shaped horn that should be in contact with ~e ground. It is very important to keep the frog healthy and free from infections such as thrush.

Inside the foot, the insensitive horny laminae of the wall are attached to the sensitive laminae that in turn help to support the pedal bone. There are three bones in the foot — the pedal bone, the navicular bone, and the lower part of the short pastern bone.

Above the sole is the sensitive sole, and above the frog is the plantar cushion. All these sensitive internal junctures help the horse to feel the ground it is walking on. The frog, bars, plantar cushion, and the lateral cartilages are all elastic structures, and play a viral role in absorbing concussion.