Working with a Chronic Quarter Crack
By Michael Chance, CJF
These are pictures of a chronic quarter crack that reopened (Image 1). All farriers get this type of call and the question, “Can you do something with this? I have a show in a few days so he can’t have any time off.” First it is important to get the history. This horse was purchased two years ago with a crack in the same spot. The horse was never lame. Now, two years later, another one pops. Looking at this horse (Image 2) it is easy to see there are conformation faults that led to the crack. The foot is typical as it lands on the outside then slams the inside as the horse’s weight passes over it. The medial wall is forced higher and higher causing it to shear. The wall will shear and stress until it cracks. This is how I handled this one. First we took a good look at the foot (Images 3, 4, 5) before pulling the shoe. Notice the location of the crack at the coronary. The heel is sheared. The foot needs to be balanced. Notice that the crack is open at the coronary band. It needs to be dremeled out and soaked a few days before patching.
Now we pull the shoe (Image 6) and balance the foot. Once the foot is trimmed we float the area under the crack as well as the sheared heel. It is important to unload the sheared heel, as this entire area perpendicular to the ground needs to be non-weight bearing before the heel can settle and the crack can heal at the coronary. Even though we float the heel and unload the sheared heel (Image 7) it will take a long time, if ever, for this area to go back to normal.
I prefer a flex shaft dremel (Image 8) as the long shaft allows me to keep the motor away from the horse. Also the working end of the flex shaft is much lighter and easier to control. I use a 1/8" dremel burr. If you have never opened a quarter crack before I recommend that you attend a hands on clinic on dissection. The hoof is a vital living part of the horse and you should not attempt this without some education. At least practice on a tangerine or a tangelo. Practice taking the skin off without cutting into the pulp. When you can achieve this use an apple. When you can take off only the skin you have control of the dremel. The wall thickness at the coronary is paper-thin. When using the dremel hold it with both hands and put your hands against the hoof. If the horse should move, and they do, your hand will be pushed away instead of the dremel going into the hoof. Remember that you are only a credit card thickness away from sensitive structures so be careful. I also keep a new or sharp burr in the dremel. If it gets dull or rusty it generates too much heat.
Start at the coronary where the wall is the thinnest (Images 9,10, 11) and move the dremel down following the crack. Keep the burr moving, as heat will build up if left in one place too long. Open the crack completely and be very careful not to get too deep. On this foot the area behind the crack had been undermined and we remove all the weak wall structure. After the entire area is open advise the client to soak twice a day for at least three days, more if the crack is bleeding or infected.
After that time has passed and the foot is dry (Image 12) you can patch it with the product of your choice. I use Vettec Adhere. It is easy to apply, stays in place and sets quick without too much heat. You should always ask the owner to have their vet look at the case before you do your work. Discuss the situation with the vet whenever possible so everyone is on the same page with the treatment. It can also be helpful to have the horse tranquilized before beginning the dremel work. If you have a camera, take before and after pictures for your records.