Fig. 8. Tenotomy rail shoe glued onto a hoof boot. The wedge minimizes distal interphalangeal joint subluxation post tenot- omy. The heel extension prevents hyperextension of the distal interphalangeal joint post tenotomy.
Trimming remains the same regardless of the method you prefer. With radiographic guidance, the heels are trimmed aggressively without invad- ing the live sole. Most cases are rarely trimmed at all forward of the widest part of the foot. This ensures as much foot mass as possible remains be- neath the tip of P3. Some horses may require ad- ditional toe elevation to achieve a 0° solar margin angle relative to the boot bottom. Cutting a wedge pad to match the interior of the boot and placing the thick portion at the toe accomplishes this well. The support option of choice can then be placed on top of the wedge pad. Radiographs should be taken to ensure that the desired phalangeal align- ment has been achieved. An extremely well-fit boot is required for this technique. Without a snug fit, the toe can flip up within the boot resulting in seri- ous heel bulb rubs or sores. In addition, the heel extension provides leverage that can predispose the boots to twisting on the foot. The author prefers to use glue-on shoes following a tenotomy because they require less maintenance and he is comfortable with glue-on techniques. Boots with heel extensions are used by the author most commonly to give horses a break from shoes. This is done for a variety of rea- sons including soreness, hoof wall deterioration un- der glue, etc. (Figs. 9A and B). Modified hoof boots may provide practitioners an alternative method of derotation shoeing. This could be especially bene- ficial in situations where the farrier and/or practi- tioner are not comfortable with the traditional glue-on derotation technique.
Using Hoof Boots to Treat Distal and Mediolateral Displacement (Sinkers)
Distal and mediolateral displacement is the most challenging manifestation of chronic laminitis to
Fig. 9. A, Radiograph of a hoof 6 days post tenotomy of the DDFT. Laminitis was supporting limb laminitis due to a severe injury to the contralateral limb. Shoe was removed due to unrelenting foot pain across the entire sole. B, Same foot in panel A is shown following shoe removal and placement in a modified hoof boot. A hoof boot with a tenotomy rail shoe glued to the bottom was applied. A double layer of felt padding was used for support. The mare was more comfortable but not to a humane level. Boot was used for a couple of days at which time a transfixation pin cast was applied. To date, 4 months later, she is expected to have a good quality of life and be able to perform her duties as a broodmare.
