One of the things I’ve always feared is dealing with hoof cracks,
specifically toe cracks. Conventional crack treatment usually requires frequent monitoring and additional follow-up repairs.

From the 1970s to the 1990s, I relied on screws and wire to repair primarily medial quarter cracks that occurred in Thoroughbred racehorses. But if the horse happened to step on the repaired area, it normally had to be redone.

Different Repair Options

After abandoning the use of screws and wire, I started using fiberglass and Equilox, which didn’t create the bulge in the hoof that lacing with screws and wire did. While fiberglass resulted in a low-profile repair area on the hoof, it had a tendency to crack after several months, leading to the need to remove the material and perform another complete repair.

Farrier Takeaways

  • Burning horizontal grooves helps California farrier Bob Shirley arrest the progression of hoof cracks.
  • Using Equilox adhesive provides horizontal support similar to lacing your shoes provides foot support.
  • Using an electrically-heated iron, Shirley burns the depth of the blade.

As many shoers have done, I’ve burned horizontal grooves perpendicular to the crack with a forge-heated iron. However, the results for me were usually limited and disappointing. The forge-heated iron cooled very quickly, making it difficult to burn deep enough into the hoof wall.

I’ve long felt that if there were a way to provide horizontal strength to the crack such as a staple might provide, then I might be able to eliminate the crack progression. I’ve tried hammering staples into the hoof wall, but it proved difficult to keep them from collapsing.

I’ve also used a hacksaw blade to cut horizontal grooves in the hoof. However, these grooves usually weren’t wide enough and sawing through the hoof was more difficult than I’d anticipated. I even used a Sawzall, but horses hated the vibration and wouldn’t tolerate the noise.

Deep Grooves

What I’ve ended up using for crack repair is an electrically-heated iron to burn deep grooves into the hoof wall. (Figure 1)

The depth that I burn is a subjective decision based on breed and my own personal experience. A draft horse has a larger, more robust hoof and a thicker wall when contrasted with a Thoroughbred or Quarter Horse, for example.

The wall thickness at the toe is about 3/8 to ½ inches.1 I routinely burn the depth of the burning blade, and this might be the safest approach. Since the horse will let you know when you’re getting close to a nerve, I’d hesitate to sedate a horse that you will be “burning.”

The hoof wall thickness in the quarters is significantly less than at the toe, so keep that in mind when burning deep grooves. The hoof wall also thins out as you get closer to the coronary band.

Since I’ve had a few horses “spook” and become agitated at the smoke from the burning process, I use an extremely quiet Ryobi 18-volt fan to blow the smoke away.

On this case, simply burning several horizontal grooves was all that’s needed (Figure 2) to stop the crack. If the crack does continue, Equilox would then be used to fill in the grooves (Figure 3). The grooving and subsequent Equilox “fill” provides horizontal support, somewhat like lacing up your own shoes provides foot support.

The hoof of the Thoroughbred mare shown in these photos competes on the local show jumper circuit. After several shoeings, the crack appears to be growing out with just simple grooving (Figure 4). She is ridden and jumped 45 minutes a day, 6 days a week. She moves much better since the toe crack has been repaired, according to the rider.

When filling a crack with Equilox, make three or four rows of grooves. Clean the grooves with a wire brush and/or coarse sandpaper before using a hair dryer or heat gun to warm and dry the area prior to applying Equilox. I avoid using degreasing solvents as my experience has shown Equilox bonds better if solvents, especially acetone, are avoided. If alcohol or any solvent is used, make sure evaporation is complete before applying the acrylic.

When using Equilox, I have little concern for the presence of any infectious organisms. Because of the temperature reached during the grooving process, the likelihood of these organisms surviving is remote. A dirty wire brush could introduce some contamination, but this can be eliminated by dipping the brush before use in betadine solution.

Here’s hoping this information proves useful to those of you who have been as frustrated as me in dealing with hoof cracks.


  1. Redden RF. Clinical and radiographic examination of the equine foot, in Proceedings. 49th Annual American Association of Equine Practitioners Convention 2003;169 –178.


July/August 2018 Issue Contents