Page 57 - November 2017

Support-limb laminitis, when a healthy leg used to support an injured leg forms a sore due to constant pressure and compression of the laminae and blood supply, can be helped with consistent movement and with the use of circulating ice water. Steward believes a shoe that simulates a horse walking on hooves compacted with balls of snow and ice, such as in the winter, can help &/or prevent support- limb laminitis due to the cold and the ball-effect movement.
By doing these things, we halt any further damage to the laminae and they can start to heal.
The solid base of the wooden shoe helps redistribute the weight of the rehab foot. Using this system along with a hoof cast will not allow the foot to spread and will enhance the re-establishment of an arch.
move in any direction with ease, similar to a horse walking on four balls of ice in the winter due to packed snow buildup in the foot or shoe,” he says. “This could possibly help pre- vent support-limb laminitis because of the ice effect (cold) and the ball effect (movement).”
Various methods need to be explored to achieve movement in a foot that is not mov- ing. “For example, we could attach a vibrating or motion-producing machine to the base of the bubble shoe,” he says. “One such machine is a ‘jitterbug’ or vibrating probe that people use in pouring concrete walls. If we could
get that horse to move the foot just a little
bit (consistently), we could probably prevent support-limb laminitis.”
The movement would break the constant unrelenting pressure and, if a person could also circulate ice-water in the shoe and leg, that would also help.
Support limb laminitis is what ultimately led to 2006 Kentucky Derby winner Barbaro being euthanized. During his recovery from surgical anesthesia, a floating raft system, which was proposed by Steward 40 years ago, was used while he woke up. Another idea Steward proposed is called a counterbalance sling. In this, you put the horse on a walker with a cable over to the horse and sling. A
bag filled with water is on the other end of
the cable. If the horse will tolerate the sling, you could then determine how much actual pressure is on the feet. The horse could even lie down in the sling if he desired.
“He could be allowed to walk around the walker with 10 pounds of pressure, or 500 pounds, or whatever he could safely stand and tolerate, without overload,” says Steward.
The laminae are like Velcro and, if it’s been damaged and the horse walks very much, he will continue to tear it, and the coffin bone will drop inside the hoof capsule.
Another common problem with horses’ hooves is that they lose their cup, or arch. Foals are born with a nice round foot and then it slowly spreads out. “When a human foot spreads and loses its arch, you can get a spur on your heel (plantar fasciitis),” he says. “For a human, you provide arch support. For a horse, it’s hard to provide arch support because of the open shoe. The wooden shoe, having a solid base, helps move the weight back to the sole to redistribute weight to rehab the foot. This system, combined with application of a hoof cast, does not allow the foot to spread and thus enhances the re-establishment of a cup (arch).”
We often talk about sole depth, and it’s very important to have good depth so there will be some protection on the bottom of the foot and so the blood vessels can open up between the bone and the ground.
“But when you have enough cup in the foot, you are moving the coffin bone even farther up off the ground and allowing the blood vessels room to open up,” Steward says. “I often ask people which they would rather have—a flat- footed horse with 15 to 20 millimeters of sole or a horse that has a good cup and only 7 mil- limeters of sole depth. The latter is usually best most of the time because a flat foot has more challenges. Yet, a lot of horses become more and more flat-footed the more we shoe them with typical shoeing methods.
“There are many things we could do to save the life of a laminitic horse and get him back to normal, if we would just do it before the snow gets too heavy on the roof!
“As veterinarians, we tend to treat lamini- tis as an entirely chemical-medical problem. We start giving the horse chemicals (medica- tions), which do nothing to fix this mechanical problem. The chemical (medical) issue may have already resolved itself a week ago and
now it’s time to give the horse the mechanical support; the mechanical issues have become
the most important at this time. The medi-
cal dysfunctions are often resolved before the laminitis manifests itself. The veterinarian or farrier always needs to address the mechanics of the situation to enhance the hoof’s ability to stabilize and heal itself.
“And don’t just do a little bit of mechan- ics. Many people put SoftRide shoes on these
horses and these are better than regular shoes because they are softer, but these are like clown shoes—the bigger shoes increase the lever on the hoof wall. We need to reduce that leverage and shear forces and tension forces to the laminae. The roller motion shoe gives a better effect.
“Between 7 and 15% of all horses will suffer laminitis to some degree at some point in their lives. About 10% of those cases are devastat- ing, to the point the horse should be put down. You want to avoid this by keeping the laminae intact as much as you can. It’s like jumping
out of an airplane with a parachute. You might have 10,000 cords holding you to that chute, but if someone cuts half of those, you could be in trouble. If they cut all but one cord, you will definitely drop and you are going to die. How much you weigh and how hard you bounce on those cords determines how many of them it will take to hold you up.”
It’s the same with the laminae that hold the coffin bone to the hoof wall. When a lami- nitic horse is forced to stand while hauling, this unrelenting weight on the feet, without mechanical support for the laminae, is even more damaging and painful for the horse.
“This is the hard part for horses that are brought to me for treatment, having to travel in a trailer without proper hoof support. If the horse will lie down in the trailer, it’s a lot better and not so damaging to the distressed laminae.”
SPEEDHORSE, November 2017 55
EQUINE HEALTH