Last month, we talked about some of the more common foot abnormalities that we see here at Hayes Equine: the long toe/low heeled horse, the club foot, thin soles, and laminitis. Each of these abnormalities predisposes the horse to significant lameness issues. While we all know what the typical, chronic laminitic horse looks like, many of us don’t realize that the long toe/low heel conformation can contribute to caudal heel pain. And thin soles can make even a normally sound horse look like a laminitic horse on hard or rocky surfaces. While some of these problems can only be managed, some of them can actually be fixed with the right combination of owner compliance, diet, veterinary care, and thoughtful shoeing.
The key to remember when attempting to make a horse more comfortable through podiatry is that the foot has a blood supply. Without blood, the foot can’t grow. Take a look at this venogram:
This is what the blood supply looks like in a healthy horse foot. As you see, the foot has a large amount of tiny little vessels all around the bone that supply the foot with oxygen and nutrients. This includes BELOW the coffin bone, which is where the biggest trouble spot is.
Now, I want you to take your right thumbnail and press it to the nail on your left middle finger. What happens? Did your nail bed turn from pink to white? This is because just that small amount of pressure pushed all the blood out of the tiny vessels between your nail and your finger bone. This same thing happens when your horse places his weight on his foot. The coffin bone compresses all those vessels underneath it. However, if you have enough padding, the vessels don’t get compressed nearly as much. Just like if you put on thick gloves and try to compress the vessels in your finger.
Remember, without blood, a horse can’t grow foot. In order for a horse to be able to stand and walk comfortably, there must be enough “padding” to avoid compression of these vessels. This can be in the form of foot, or in the form of artificial substances that your farrier applies. A horse needs a minimum of 15 mm of sole to be comfortable on all surfaces.
Lameness caused by any of the issues we talked about last month can in some form be attributed to not enough foot between the coffin bone and the ground. The key to making these horses more comfortable is to establish more blood flow and correct angles through the use of corrective shoeing. However, this involves a relationship between owner, veterinarian, and farrier. Proper nutrition, the treatment of underlying issues, and the use of x-rays involves all of these people.
One of the best ways to correct the four issues talked about last month is through the use of a rockered rail shoe, developed by Dr. Rick Redden. This is a special shoe that has had a bend added to it through the use of a special jig. This allows the horse to “rock” the foot forward or back, and allows him to adjust his stance to a more comfortable position. However, rocker rail shoes must be carefully applied with the use of x-ray guidance, to allow the farrier to make sure the rocker is in the correct position, and that the shoe isn’t putting too much pressure in the wrong areas. It also allows the veterinarian and the farrier to evaluate the alignment of the bones.
In the long toe/low heel horse, the rocker rail is used to get the bones into a better alignment. Notice how, with the application of the rocker rail, the bones are in much better alignment. This has taken all the pressure off the soft tissue structures on the back of the foot like the deep digital flexor tendon and the navicular bone.
For club foot, thin soles, and laminitis, the use of the rocker rail not only puts the bones in correct alignment, but it also takes the pressure off the part of the sole under the coffin bone, allowing for increased blood flow and subsequent growth. Once growth under the coffin bone is achieved, corrections can be made slowly to the foot to allow it to grow in a more natural position. The horse in the following pictures went from 5mm of sole to 16mm of sole in about 4 months through the use of the rocker rail:
When applied to the club foot horse, the rocker rail also allows for more growth of the sole, allowing for better comfort. While it can’t fix the tendons that are causing the horse to be “clubby,” at least it can make them comfortable enough to go without a shoe.
In the laminitic horse, we can actually get them to have a normal foot through the use of the rocker rail:
Even though the horse in these pictures is in a different shoe in the second picture, it is still the same horse about a year after the first picture was taken. You can see how there is a ton of sole and the coffin bone is in alignment with the front of the hoof capsule.
Rocker rails are obviously not the solution to all problems. However, it’s amazing what can be accomplished through x-ray guided shoeing. A lot of horses that were previously lame can be made a lot more comfortable just with changing the way their foot falls. If you have any questions, or wish to attempt a rocker rail, please feel free to call your veterinarian for more advice.