| Barefoot methodology and the correlation to hoof casts Stephen E. O’Grady, DVM and Derek Poupard, CJF
I have always been a proponent of maintaining a horse barefoot when possible. The equine foot with healthy structures is superior in its natural or barefoot state as opposed to the shod state with regards to accepting the weight of the horse, shock absorption and dissipating the energy of impact (Davies 2007). However, the domestic use of the horse invariably necessitates applying shoes for several reasons:
It must be stated from the onset that traditional farriery can be performed in a proper physiological manner with minimal damage to the horse's foot (O'Grady and Poupard 2003; O’Grady 2010; O'Grady 2019). However, there are many aspects of barefoot methodology that can be applied to or combined with traditional farriery and warrant consideration. The first author has been consistently successful in improving the structures of the hoof capsule, especially the palmar section of the foot, in a huge number of horses by leaving the horse barefoot for a given period of time. See here.
The effect of applying a horseshoe There is no doubt that applying a horseshoe to a horse's foot will change the density and the functionality of the hoof structures. The structures of the equine foot in the barefoot state have the unique ability to adapt, strengthen, change shape, and restore. When barefoot, the structures of the foot function as a group in a ‘load sharing’ arrangement. A brief look at the effects of applying a horseshoe to the horse’s foot may highlight the potential benefits of being left barefoot or left barefoot for a brief time. A horseshoe is continually referred to as an extension of the horse's foot although this statement may not be accurate. Placing a horseshoe with different properties than the hoof capsule between the hoof and the ground replaces a single interface with 2 interfaces which will invariably have consequences on foot function. This interface alters the concussion-dampening effect on the foot / lower limb, which results in an increase of impact intensity on the hoof. Applying a shoe elevates the hoof off the ground surface and loads the bearing border of the hoof wall; this elevation lifts the sole and soft tissue structures of the palmar foot above the ground surface which changes the interaction of these structures and the elevation, combined with attaching the shoe with nails, results in less heel expansion compared with the unshod foot. A huge component of shock absorption is the hemodynamic system of the foot which will invariably be compromised to some extent by this selective loading of the bearing border of the hoof wall. The process of hoof growth and wear when barefoot allows the horse to maintain the shape of the foot as friction and thus wear occurs between the ground and the entire solar surface of the foot. When a horse is shod, wear occurs between the expanding heel of the hoof capsule against the shoe which induces greater wear at the heel compared with wear at the toe which changes the conformation of the foot.
Hoof casts – the correlation Over the years, I have used casts in veterinary practice to treat foot problems where indicated but was never an advocate for using them in farriery. My main concern was the restrictive nature of the cast that impeded the physiologic function of the foot and the inconsistent methods of application. Recently, my old friend and excellent farrier, Derek Poupard, CJF, DipWCF has pioneered a consistent technique for cast application that provides protection and stability yet does not interfere with foot function. There is no reason why this application should not become a viable aspect of good basic farriery. The negative perception of shod vs. barefoot, whether transient or permanent, is the animal’s comfort and maintaining the integrity of the foot when removing the shoes. Scenarios where a cast is beneficial:
Application of the cast I will describe the salient points of the cast application which will be followed by a video of Derek showing the actual application. The foot to be casted is brushed briskly with a wire brush…no horn is removed from the solar surface of the foot. If possible, the heels of the hoof capsule are trimmed to the plane of the frog. If the frog descends below the ground surface of the foot; it will be repositioned by the weight of the horse shortly after the horse is barefoot. I then draw a line across the widest part of the foot and look at the proportions on either side of the line. If the dorsal proportion of the solar surface is excessive, the toe length is reduced from the perimeter of the foot. The outer surface of hoof wall at the heels is cleaned with a rasp and the remainder of the outer surface is sanded using a 3M® medium grit sanding block. A thick focal layer of an acrylic of your choice is applied to the heels as this will act as the anchor point to stabilize the cast. A thin layer of acrylic is randomly spread on the remainder if the outer hoof wall stopping below the coronet (Figure 1).
Starting at the heels, 2- or 3-inch casting tape is wrapped around the foot. The cast is applied without being immersed in water as this will improve the bond with the acrylic. The cast will extend to the coronet and a .5 inch below the hoof wall to create a fold onto the ground surface. The cast can be thickened at the heels and or quarters by creating some folds by layering the cast back and forth and then enveloping the folds as one continues to wrap (illustrated in the video). With the cast in place, a sponge is used to thoroughly wet the cast which causes it to cure. Finally, the cast is covered with plastic wrap and the foot is placed on the ground (Figure 2).
The unique part of this application…once the cast is dry, using the edge of the rasp, the cast is scored on either side from the frog sulci to the edge of the cast at the heel bulb. The score lines are now cut through using a thin hoof knife or some form of saw blade or gigli wire. The section of cast that covers the base of the frog is removed and the edge of the cast are smoothed with a rasp and blended with the heel bulb (Figure 3).
Finally, any cast material above or at the coronet is removed by light rasping as the acrylic does not extend to coronet, so cast is not adhered to this area (Figure 4).
It can readily be noted that the application of a hoof cast as described above affords protection and stability of the hoof capsule while allowing the full physiological function of the foot. This method of cast application has huge implications when considering any aspect of barefoot methodology. It must be remembered, when a horse goes from being shod to barefoot, the horse needs time to adapt and strengthen the structures of the foot. The reluctance of many veterinarians, farriers, and horse owners to use the barefoot modality is the initial discomfort the horse may experience and the damage to the hoof capsule without the protection of a shoe. Here is a hoof cast application that will bridge that gap while allowing the structures of the hoof to adapt, strengthen, change foot conformation, and restore.
Enjoy the video…
Be safe |
Addendum... hopefully, this hoof casting modality will be used by both the veterinary or farrier profession (or together) and knowing that veterinarians may not be as skillful as a farrier using a hoof knife; there is another method of removing the heel section of the cast. I use a hacksaw blade handle (available from Amazon ® ) which can be used with one hand and cuts easily through the cured cast. Make a score line from the frog sulci to the edge of the cast at the heel bulb on either side and then carefully cut through the cast.