Virginia Therapeutic Farriery

The Practical Application of Bar Shoes

Reprinted with permission from Farrier Products Distribution
Original published in The Natural Angle, Volume 12: Issue 2.

Stephen E. O'Grady, DVM, MRCVS

Bar shoes could be considered thefoundation of therapeutic farriery. Abar shoe is one in which the heels arejoined to form a continuous unit ofsteel or aluminum. There are severalpatterns of complete bar shoescommonly used in therapeutic farrieryincluding the straight bar, the egg bar,the heart bar, the heart bar-egg bar (fullsupport shoe) and the "Z" bar shoe. Itis important to realize and understandthe multitude of benefits a bar shoecan provide such as increased stabilityof the hoof capsule, increased groundcontact surface, local protection andrecruitment of additional weightbearing areas of the foot. Furthermore,they decrease the independent verticalmovement of the heels and provide theability to unload or support a sectionof the foot. Placing a bar between theheels of a shoe adds several inches ofsurface area to the foot, therebyreducing movement and stabilizing thehoof capsule. The additional groundcontact surface also seems to preventthe palmar-plantar section of the hooffrom sinking into deformable surfacesproviding a "flotation" effect. Thiseffect appears to be helpful whentreating palmar foot pain as it seems tolimit the extension of the distalinterphalangeal joint during theimpact phase of the stride.

Figure 1. Kerckhaert straight bar shoe
Figure 2. Example of a trimmed foot showing guidelines. Black line equals widest part of the foot. Red line shows proportions of foot on either side of widest part of foot.
Figure 3a. Straight bar shoe fitted to the foot with shoe placed in middle of the foot (Black line)
Figure 3b. Shows the heel base of a fitted straight bar shoe. Note the sheared heel.
Figure 4. Welds smoothed with a grinder and the heel base is boxed.

I use a tremendous amount ofstraight bar shoes in mypractice. Historically, bar shoeshad to be forged from bar stockor a bar had to be weldedbetween the heels of the shoebut recently many types ofwell-designed bar shoes havebecome available commercially.I exclusively use the Kerckhaertstraight bar (Figure 1) formany reasons but especially forits ability to stabilize the hoofcapsule and with the straightbar shoe there is no excessleverage applied to the heelswhich is often the case whenegg bar shoes are applied.Some of the conditions I use astraight bar shoe for are palmarfoot pain, sheared heels,quarter cracks, white line disease,distal phalanx fractures along with acontinuous rim and any conditionwhere the stability of the hoof capsuleneeds to be enhanced. The straight barshoe is often combined with a leatherpad and impression material placed inthe palmar section of the foot to treatweak heels.

Before fitting and applying a bar shoe,it is necessary to briefly discuss thetrim. The trim forms the foundationfor either routine or therapeuticshoeing therefore if the trim is notappropriate, whatever shoe is used willbe less that optimally successful. Inshort, there are only three basicvariables that can be altered by thetrim, the depth of sole, angle of thedorsal wall, and mediolateralsymmetry. The length of the wall atthe toe is predicated on the depth ofthe sole; the wall is either level or slightly longer than the adjacent sole.The length of the heels is thenpredicated on the length of toe and theangle of the foot-pastern axis. Placedin practical terms, a line can be drawnacross the widest part of the foot, thetoe/quarters are reduced according tothe sole depth and the heels aretrimmed such that the heels of thehoof capsule and the frog are on thesame plane. The proportions oneither side of the line drawn across thefoot should approximate each other(Figure 2). It should be noted that ifthe frog protrudes below the hoof wallfollowing the trim, if possible, thehorse is placed on a hard firm surfacefor 24 hours without shoes. This will place the frog and the hoof wall at theheels on the same plane beforeapplying the straight bar shoe.

The Kerckhaert straight bar shoe has avery good shape and can generally befitted cold and finished with a grinder.This is certainly not to discourage theuse of a forge. If the foot is distortedor if the proportions of the shoe needto be altered for therapeutic reasons,then the use of a forge becomesnecessary. The shoe is fitted to thefoot such that the line drawn acrossthe widest part of the foot is located inthe middle of the shoe and the bar isallowed to extend up to a half inchbeyond the end of the heels of thehoof capsule (Figure 3A, 3B). Thisforms an excellent base under theheels. The shoe is back punched asnecessary and additional nail holes arepunched if needed. The shoe is nowfinished either by forging or using agrinder. The welds used to attach thebar on the foot surface of the shoe aresmoothed out so as to not interferewith the movement of the heels of thehoof capsule against the shoe and theouter perimeter of the foot surface ofthe shoe is boxed from one quarter tothe other quarter to prevent the horsefrom inadvertently stepping on theouter margin of the shoe (Figure 4). It must be remembered to remove theleading edge of the bar on theground surface of the foot to preventdrag during the landing stage of thestride (Figure 5). For enhancementof breakover, I use a grinder and startthe roll at the inner margin of groundsurface of the horseshoe at the toeand create a tapered roll from thispoint to the outer margin of thehorseshoe such that the result willdecrease the thickness of the outermargin of the shoe by half thethickness of the material (Figure 6).The shoe is attached to the foot usingfour nails of the smallest size possiblethat fit the holes punched in theshoe.

An example of using a straight barshoe would be for a foot with asheared heel and a quarter crack(Sheared heels will be discussed in afuture edition of The Natural Angle).The objective for this condition is tounload the sheared heel and allowthe heel to descend into a moreacceptable position. This can onlybe accomplished with a bar shoe.After the foot is trimmed asdescribed above, the foot is loweredfurther from the quarter to the heelon the affected side before the shoe isattached. A leather pad is usuallyused with the shoe and impressionmaterial is placed in the palmarsection of the foot except under theaffected quarter and heel to furthershift the load to the contralateral sideof the foot and encourage thesheared heel to drop (Figure 7).

Figure 5. Leading edge of the bar is beveled with a grinder to remove "drag" and allow the foot to slide on impact.
Figure 6. Breakover is created in the shoe with a grinder beginning at the inner margin of the shoe at the toe.
Figure 7. Example of a straight bar shoe with a leather pad and impression material being used to unload a sheared heel with a quarter crack.