Low heels, also called underrun or collapsed heels, can be a frustrating cause of lameness in horses. Further, the effects of the shoeing strategies used to correct them can actually be detrimental in the long run.

So Simon Curtis, FWCF, BSc(Hons), PhD, HonAssocRCVS, an award-winning farrier based in Newmarket, Suffolk, U.K., proposed a long-term solution to the issue at the 2018 British Equine Veterinary Association Congress, held Sept. 12-15 in Birmingham, U.K.

While the terms low and underrun are often used interchangeably when describing horses’ hooves, they do differ.

“A low-heeled horse is one where the digit has a low angle but aligned hoof-pastern axis (HPA, how the front hoof wall aligns with the pastern) and the caudal (rear) hoof wall is not bent,” Curtis explained. “Underrun heels are associated with a negative HPA (when the pastern angle is steeper than the hoof wall) and are long and folded under the solar hoof capsule.”

Many things can cause low heels, he said, including:

Breed;

Hoof conformation;

Genetics;

Weak hoof wall;

Lack of proper hoof care;

Poor trimming and shoeing technique; and

Improper shoe fit.

Regardless the reason, excessive loading on the back of the foot causes the heels to compress and bend. This exacerbates the negative HPA even further, said Curtis, creating a deteriorating cycle in which new hoof growth is continually exposed to increased loading.

The first step in halting this cycle is rebalancing the hoof, starting with trimming. You want to trim the long toe back without removing so much that it compromises the hoof wall’s structural integrity, Curtis cautioned. Then trim the heels as far back as is safe and possible.

“In recent years it has been suggested that a farrier should trim the heels to the ‘widest part of the frog,’ ” he adds. “This is dangerous nonsense as it is only possible to fulfill this formula by trimming into the sensitive tissue.”