The equine chestnut and forearm

...and on the eighth day God created the horse in perfect image, to romp, graze, gallop, play and make manure wherever it darn well pleases in divine grace.

In anatomy and conformation, the forearm is the part of the horse’s front limb between the knee and the elbow joint.

The chestnuts is a mass of horn-like tissue that is located on the inside of the forearm, just above the knee. (1)

Did you know that no two chestnuts are alike?

This is fact, and because no two are alike, they are considered to be quasi-fingerprints for identification of an animal.

Horse racetracks were actually considering chestnuts as identification markers with the usage of the shape of the chestnut, in the event that a “substitute” horse with an identical tattoo could not be used in its place.

However, with the dawning of the science of DNA and its subsequent technology, this identification method has been abandoned. (2)

The two bones located in the forearm are the ulna and the radius. The ulna is a short bone fused to the upper portion of the radius. The radius is solid and its ends go into the elbow joint at the top, and go into the carpus at the lower end.

The “olecranon process” of the ulna projects beyond the elbow joint to form the point of the elbow. It serves as a lever of attachment for the muscles that extend the elbow itself. (3)

The ulna bone in the horse is small, in comparison to other animals. It works in combination with the fusion to the radius, this keeps the forearm from rotating outward and backward.

A forearm that is well-conformed is wide, long, well-directed and thick. It is straight in line with the knee and cannon bone, from all views.

A long forearm that is in proportion with the entire equine body gives the animal more length-of-stride.

View the forearm from the side. When it has good width and it is in balance with the rest of the equine body, is very desirable, since major muscles for propulsion and strength are attached at this location. (4)

There is very little body fat located here, and when viewing forearm muscling in this area, it is a good indicator of the degree of muscling for the entire body of the equine. Most of the muscles are located at the top of the forearm, and the leg then becomes slimmer and tendinous as it goes down toward the bottom at the hoof. The muscling should not be bunched-up and short, but rather lengthy and smooth.

When viewed from the front, it should be strong and thick because of the underlying muscles located there. (5)

“Calf knees,” “Tied-in knees,” and “Bucked knees” can ruin the conformation appearance of the horse, as does, “Knock” and “Bench knees.” These problems can affect the weight-bearing ability of the horse, also, and pre-dispose it to injury. (6)

Consult your Veterinarian if you suspect your horse may have conformation defects, or issues with the forearm or knees. The Vet can help determine a work-regimen that is suitable for such an animal, so that it is not overworked or injured

That’s all for now.

Enjoy the upcoming Fall weather to the immortal words of Roy Rogers and Dale Evans, “Happy Trails to You.”

1-6: “Horseman’s Veterinary Encyclopedia,” by Will A. Hadden III, DVM