This invention relates to an attachment for an equine boot that allows the boot to rotate forward having a break-over point near the centerline, front to back, of the sole of the boot. Specifically, it relates to an attachment for the underside of an equine boot that allows the boot to rock thus allowing a horse to find a naturally comfortable position.
It has been reported that the estimated economic loss due to lameness in horses is between $678 million and $1 billion annually (USDA-APHIS, 2001). Although there are many reasons, sole bruising and disease such as laminitis are a common causes of lameness in horses. A thin sole provides insufficient protection to the foot and predisposes a horse to sole bruising (Stashak, 1987; Dabareiner et al., 2003). Lack of adequate sole thickness may be predisposed by genetics or caused by laminitis or injury. See Article Professional Animal Scientist, December 2006 by Haffner, J, Wooten, M, Dunson, D, Bowers, D, Hoffman, R.
As explained in the website www.therapeutichorseshoeing.com “Laminitis or “founder” is an equine hoof disease where the coffin bone (third phalanx, P3) begins to lose its attachment to the inner hoof wall and begins to rotate toward the front of the hoof or sink within the hoof capsule. Laminitis is generally thought to result from an imbalance in the horse's internal system. For example, an injury or upset to some part of the body is combated by the circulatory system as blood rushes to the injured area. The momentary reduction in blood flow deprives the capillaries which feed the lamina. The lamina is the “velcro” that attaches the bone to the hoof wall. In the brief time the lamina lacks sufficient blood flow, the capillaries begin to die and the “Velcro” attachment is weakened. The deep flexor tendon is attached to the bottom (palmar surface) of the coffin bone. This tendon is an extension of a muscle which reacts to the pain of the tearing lamina. As the muscle contracts, the tendon is in tension and pulls on the coffin bone. Once this pain cycle is established, it must be broken before healing can begin.” While lameness, especially that caused by laminitis is difficult to cure, it is possible to relieve some of the pressure and pain by use of proper trimming, shoes or boots that allow the horse to find a comfortable position and to relieve unnecessary pressure on a lame hoof. Such relief is often essential to an eventual cure.
One commercial shoe that has found acceptance is sometime called a “banana” or “rocker” shoe or clog. This is a shoe that is shaped to allow break-over adjustment by a “rocker” effect of the sole of the hoof so that the horse can more easily find a comfortable position by adjusting the palmar/planar angle to take pressure and stress off affected areas of the hoof. The “Clog” is a shoe developed by Dr. Micheal L. Steward, DVM of Oklahoma is one of the first to use the concept of a self adjusting in a wooden shoe that is screwed and/or glued directly to the hoof. Adaptations of the Stewart Clog have been made of other materials. These shoes, while somewhat effective are attached directly to the hoof and are not, therefore, easily changed without damage to the hoof. The present invention is a boot with an attachment that overcomes deficiencies of other shoes or boots.
This invention is an equine boot attachment that allows the boot, and therefore the equine hoof to roll forward, or to the side, without unnecessary bending, thus allowing the horse to find a comfortable natural position to relieve stress on a sore, injured or diseased hoof. The rocking action allows the equine to adjust its stance to find the most comfortable position, not unlike standing in a bed of sand. This ability to find a naturally comfortable standing position is especially important for equine with lameness such as laminitis.
In one aspect the invention is a “rocker” attachment for placement on the underside of an equine boot that allows the boot to rotate forward and back having a break-over point within about two inches of the centerline of the boot, measured front to back.
In another more detailed aspect the invention is an equine boot assembly having an equine boot comprising; an upper section made from flexible material shaped to fit around the hoof of a horse comprising a front, sides, and rear, a fastening means to fasten the front and rear together around the leg of a horse, a bottom section, a solid sole plate and optionally an elastomeric pad disposed inside the boot and: a “rocker” and optionally a spacer attachment for the underside of the bottom section that allows the boot to rotate forward having a break-over point within about two (2) inches of the sole centerline, front to back, of the bottom section of the boot. The rocker attachment may comprise two components, one harder component immediately beneath the sole of the boot (and preferably patterned to mate with the contours or pattern on the underside of the sole) to which a “rocker” attachment is secured. The rocker may be adapted to have its position adjusted on the spacer.
One benefit of the present invention is that it can replace expensive hoof treatment by a Ferrier and can easily be utilized directly by an equine owner.
It is also, in one embodiment, a kit for providing an attachment to the underside of an equine boot comprising an attachment, in one or two pieces, shaped to allow the boot to rotate forward and back having a break-over point within about two (2) inches of the centerline of the sole of the boot (front to back), specially adapted to fit the boot sole to which it is to be attached and a means of attaching the attachment to the boot sole.
The “rocker” attachment of the present invention comprises an attachment, or permanent projection, for the underside or sole of an equine boot, that allows the boot to rock forward—break-over when tilted, as by movement of the equine leg, thus allowing the equine to find a naturally comfortable position. Horses that are lame, by laminitis or otherwise, will naturally seek a comfortable standing position. When standing, walking or running the horse will greatly benefit from the ability of the boot, and thereby the hoof, to roll forward or backward without unnecessary bending that puts pressure on the toe of the hoof. The “rocker” attachment and boot of the present invention accomplices that. By moving the break-over (lever-arm of the hoof) back from the front of the hoof, pressure is unloaded from the hoof wall so that the hoof lamina does not have to do all the work of holding the bony column of the hoof and leg to the furthest point out toward the front of the hoof. Without a rocker shoe or boot the pressure in on the front hoof wall when the hoof is tilted forward. Break-over, as the term is used herein, is the last point of the hoof or shoe to come off the ground when the horse is moving. The further forward the break-over is, the more levering affect there is placed on the foot and potential strain on the entire back portion of the limbs
The sloped front of the boot sole described in U.S. Pat. No. 7,445,051, issued Nov. 4, 2008, D565256, issued Mar. 25, 2008 and U.S. patent application Ser. Nos. 11/652,187 filed Jan. 11, 2007 and 12/284,925 filed Sep. 24, 2008 provides a more gentle and beneficial break-over than conventional shoes or boots but often more assistance is needed. The present invention adds greatly to that benefit by moving the break-over point further towards the rear. It also allows ready customization and adjustment of the break-over point.
A significant advantage of the rocker attachment of the present invention is that it does not require special training or specialized farriers. Other currently available clog shoes and other metal rocker shoes have to be specially fitted and attached directly to the hoof if improperly fitted such attachment can cause more harm than good. Badly fitted shoes can permanently cripple a horse. The present invention is easily used by any horse owner and can be used even in remote areas that do not have the advantage of a local equine podiatrist available. The present invention thus provides a more economical and more readily available solutions to equine lameness.
Chronic laminitis most commonly involves the distal displacement (rearward movement/rotation and sometimes sinking) due primarily to trauma, insult or swelling of the lamina (attachment tissue) of the P3 (coffin bone or distal phalanx) to the hoof wall. The deep digital flexor tendon, (doing its job), continues to keep tension on the boney column and further pulls the P3 out of the ideal position within the hoof capsule, resulting in an alignment shift of the weight-bearing functionality of the P3 from its solar surface (bottom of bone should be parallel to the ground surface). This realignment, results in chronic pain and over time decreased sole growth (contracted heels etc.). Many realignment techniques of the P3 can not be achieved during the initial developmental stages of laminitis because the hoof capsule is unstable and continually changing. Many traditional mechanical realignment procedures like therapeutic trimming or special shoes have been very problematic, painful and traumatic to the horse; are expensive and do not achieve the successful outcomes the horse owners desire. The tension on the deep digital flexor tendon can be lessened as the horse feels is necessary yet the rocker capability of the attachment of this invention does not force the hoof into an uncomfortable, unnatural position continually. Constant severely elevated heels can have the effect overtime of continually shortening the tendon there by requiring additional procedure to comfort the animal.
The boot attachments of this invention provide an efficient, horse self-adjusting approach to sole supportive realignment of the P3 as the hoof grows out.
Referring to the Figures,
In the illustrative embodiment shown in the Figures, the length—front to back—of the attachment is about 5.5 inches, the width about 5.25 inches, the projection 16 is about 0.2 inches above the surface of the attachment 10, the point c is about 1.5 inches from the front of the attachment and the thickness of the attachment, at the center, is about 0.75 inches. These dimensions will vary to accommodate boots for the various sizes and shapes of equine hoofs.
The attachment has a sloping front, angle a, to allow it to tip forward from a point c. Point c is the break-over point of the boot/attachment assembly and desirably located below a point near the front of the distal P phalanx, P3 (coffin bone),In general, it is desirable that the break-over be within 1-2 inches, front to back, on the attachment from the front point of P3. The ideal point, in most cases will be at or within ½ inch of the front of the P3. A convenient way to locate the front of the coffin bone is draw a perpendicular line down from the hair line of the coronet band of the hoof; where this line intersects the rocker attachment will be the ideal break-over point. The angle a is generally from about 15 to 45° and preferably about 30°. In some embodiments shock absorbing pads disposed inside the boots described below will be tapered back to front. In one embodiment the taper is about 5°. When used with the rocker attachment described above this boot pad combination will allow the hoof a range of angles from about 5 to 30°. This has been found to be an especially beneficial range for a boot/attachment useful in treatment of laminitic horses. As described above the rear of the attachment 10 may also be sloped in the same manner as the front, angle a. In another embodiment there is provided slots in the “rocker” attachment—rather than holes—so that the attachment a can to be moved forward or back from the centerline of attachment means 14. The slots preferably extend about ⅜″ to ⅛″ towards the front and toward the rear of the attachment from the centerline of the screw attachment means. Preferably the slots will extend about ¼″ in each direction. This allows the attachment to easily be adjusted to move the break-over forward or rearward. This is often of significant benefit in making final adjustment to suit the particular conditions of the equine hoofs.
As shown in
The rocker attachment can be secured to the sole of the boot by any suitable means, by screws and barrel nuts as shown, 14, or by gluing or cementing or a combination of these. The screw/nut means shown is a stainless steel barrel nut (10-24, ½ inch length) and stainless steel machine screw (10-24, 1 inch length). Securing the rocker to the boot sole by removable means, as by screw/nut combination, has the advantage of allowing the rocker attachment to be easily removed or replaced and if the spacer and/or rocker is slotted, to facilitate adjustment of the break-over point. It is often desirable to use different rocker attachments during the course of a treatment—changing the position, shape and slope as desired or required to find the most efficacious boot assembly (boot/attachment combination). Alternatively, the rocker attachment may be permanently affixed to the sole of the boot, as by molding them together. Since the sole in most embodiments is molded elastomeric polymer, or rubber, it is possible to make the sole with a downward projection molded into a single piece. Such single molded sole plate will be more stable and rugged.
The rocker attachment shown in the Figures has a taper (slope) toward the front of the hoof and may also be tapered towards the rear and from side to side. While not shown in the Figures, the attachment, or projection, can slope from the centerline—side to side-side—to allow the hoof to rotate or tilt from side to side as well as forward. In general, the side to side taper will be, at the center of the sole plate, such that the outside will be from about 90% to 25% of the thickness of the attachment at the center. Tapering to the side can also be beneficial in relieving pressure when the hoof is turning since during turning there is generally the most pressure upon and therefore the most damage to the coffin bone and lamina.
The rocker attachment is intended to be designed and sized to provide the optimum break-over for most applications, however, when constructed of a molded elastomer may also be customized on-site to an individual horse or individual need with standard farrier tools such as a rasp and knives.
The attachment may suitable be made of molded elastomeric polymer. It needs to be relatively hard and rigid, but not completely so. Molded polyurethane is very suitable and convenient to work with. It is preferred that thermoplastic polyurethane of about 45 to 90 Shore A hardness be used, with Shore A hardness of 75 to 85 being especially suitable. In some applications softer materials—Shore A of about 50 to 60 are preferred to provide additional cushioning of the hoof. When the attachment is used with deep gel pads inside the boot (as described below) there may be sufficient cushioning for most situations. The spacer may also suitably be made of molded polyurethane, in which case a hardness of about 80 to 100 is preferred and Shore A of about 90 being especially suitable. The important aspect is that the hardness can easily be adapted to the individual need of the horse to which it is applied.
Polyurethanes are easily moldable in open molds or by injection molding. Other polymer materials with similar characteristics as polyurethane, such as polyvinyl chlorides, styrene butadiene styrene polymer, epoxies and the like, are also usable. Choice of these will be well within the ability of those skilled in the polymer art to select.
The rocker attachment of the present invention will work well with most available and proposed equine boots. The attachment will be adapted to fit the particular sole of the desired boot bottom, but most have elastomeric or rubber soles and adapting the attachment to fit is well within the skill of the art. It is preferred that the boots have a relatively rigid and substantial sole in order to be able to secure the attachment. Fabric or other excessively flexible boot bottoms will be unsuitable. It is also preferred that the sole plate have an upper-ward extending wall surrounding the circumference to provide sufficient rigidity and prevent distortion from the stress placed upon the rocker attachment.
In one or more embodiments the rocker attachment works very effectively with an equine boot and boot/pad assembly described in U.S. Pat. No. 7,178,321, issued Feb. 20, 2007, U.S. Pat. No. 7,445,051, issued Nov. 4, 2008, D565256, issued Mar. 25, 2008 and U.S. patent application Ser. Nos. 11/652,187 filed Jan. 11, 2007 and 12/284,925 filed Sep. 24, 2008, for which appropriate portions are incorporated herein by reference. Some features of the present invention and the boot pad assembly of U.S. Pat. No. 7,445,051 are described below.
In general, the boots described in the above patents and applications suitable for use with a rocker attachment comprise an upper portion made from flexible material shaped to fit the hoof of an animal and of a height to reach above the hoof of the animal for which it is designed. The boot has a front, sides, rear and bottom; the front slopes back and upward, the sides are lower than the front and rear so that when the front and rear are pulled together here is an opening in the sides. There is a fastening means at the top front and rear to fasten the front and rear together around the leg of a horse. The fabric bottom is attached to a more rigid sole plate comprising a molded elastomer base entirely circumscribed by a peripheral wall (or sides) defining a receiving area sized to fit over (or under) the bottom of the upper portion; said sole plate being securely attached to the lower circumference of the upper portion.
The sole plate is a preferably a separate molded piece and is attached to the bottom of the fabric upper. The sole plate helps to hold the boot in position on the hoof, and if walled around the entire circumference it prevents the hoof sliding forward or rearward while in use. Moreover, the sole plate is important in confining an elastomeric deep gel pad in place. If a relatively “soft” pad is used (as is often desirable) the weight of the horse will flatten the pad and, if there were an opening in the sole plate wall the pad would be extruded out the opening. In this case it is especially important that the bottom circumference of the boot be sufficiently strong to contain the soft pad when it is squeezed outwardly by the pressure of the horses' hoof. By having the sole plate wall entirely surrounding the circumstance the pad is held in place and will conform to the shape of the hoof and adapt to the shape of the hoof as the horse shifts position or moves.
This allows the horse to find the best natural balance position—similar to the effect of having the horse stand in loose sand. The ability to achieve natural balance is especially important for horses with injured or diseased hoofs.
The sole plate is attached to the bottom of the fabric boot. In a preferred embodiment the bottom of the sole plate is sloped upward in the front at an angle of about five (5) to thirty (30) degrees from the bottom plane. The slope begins at a point on the bottom of the soleplate twenty (20) to forty (40) percent of the length from front to rear of the sole plate. The point of beginning is preferably about ⅓ of the distance from the front of the length of the sole plate. This angled sole plate allows the horse hoof to rock forward and backward without undue pressure on the hoof. When the horse walks the boot will “break-over” in a natural way, preventing abnormal pressure on the hoof. This rocker effect is well recognized as beneficial and there are a number of commercial products, such as the “clog” and other devises designed to “rock” with the shift in body weight of the horse allowing it to achieve a “natural balance”. This semi rigid boot sole has an advantage over soft or slipper boots since it allows the horse the stability of a flat platform as well as moving the break-over point rearward at the most critical point in the arc of the swinging limb. The front tapered sole plate plus the rocker attachment provides a kind of double break-over point that provides the horse a “restful” stable platform while eliminating the high load point of its stride, especially important and more pronounced when the horse is moving forward and turning. The rotating torque during turning is when lameness shows up most and when the most damage to the lamina connective tissue occurs. The sole plate is preferably molded of polymeric elastomer material or hard rubber (having the consistency and hardness to approximate automobile tires). Thermoplastic polyurethanes (TPUs) are suitable materials for the base plate. It is preferred that thermoplastic polyurethanes of about 55 to 75 Shore A hardness be used, with Shore A hardness of 65 to 70 being especially suitable. Other polymer materials with similar characteristics as thermoplastic polyurethanes are also usable. Choice of these will be well within the ability of those skilled in the polymer art to select.
The base of the elastomeric deep gel pad (
In other embodiments, the pad will not have the triangular projection or the front projection. When used with a horse that has an abscessed or injured frog it may be desirable to use a pad without the frog support. Also the improved sole plate of the boot makes it is possible to eliminate the front projection for some applications. However, even without the frog support the front ridge projection (
It has also been found that the shape of the pad is important. Round pads have been found to not perform well in actual use as slightly elliptical pads; they tend to rotate in the boot. An elliptical shaped pad is desirable to maintain consistent fit and to prevent rotation in the pad in use. The pad is shaped to fit the configuration of the equine hoof; many horses have hoofs that, while elliptical are more nearly round. Arabian horses, as well as horses that have elongated “toes” due to injury, disease or otherwise, have narrower hoofs so the elliptical shape is more pronounced.
The base of the gel pad is made of any suitable elastomeric polymer material that provides flexibility, shock absorbency, some degree of elasticity, resilience and has dimensional stability. Polyvinyl chloride PVC, polysilicone and similar elastomers well known to those in the art are also suitable. In a preferred embodiment, the base is constructed of a cast polyurethane elastomer. For example polyurethane-casting elastomer having a Shore A hardness of from about 10 to about 70 is suitable. It is preferred that the base be of about 20 to 70 Shore A hardness and the support be of about 8 to 50 Shore A hardness. In one embodiment, very soft pads are desirable. These should be thicker than harder pads and will have a Shore 00 hardness of about 5 to 70.
In another important embodiment the base of the pad is made of components of different densities or hardness, herein referred to a duel density pad. This pad has a base, for example, comprising a front component of shock absorbing material of lower hardness than a rear component, the front component comprising the forward 20 to 40 percent of the length from front to rear of the pad and the rear component comprising 20 to 40 percent of the length of the base from front to rear, wherein the two components overlap in the center of the base that is not occupied solely by the front or rear component. A very useful pad is made with the front component comprising about ⅓ of the length, the rear component ⅓ of the rear and ⅓ overlap. It is also sometimes desirable to reverse the duel components with the harder portion in front and the softer in the rear.
A very suitable duel density pad will be made of a polyurethane elastomer; the front component having a Shore A hardness of less than twenty (20) and the rear component having a Shore A hardness of between 20 and 40. More desirability the front has a Shore A of 5 or less, and the rear component a Shore A of about 28-32. As with the single density pad, there is also a need for pads having softer front components—Shore 00 of 5 to about 70. Elastomers, such as polyurethane, can be formulated in wide range of rebound resiliencies. For the pads of this invention it is preferred that the pad material have low rebound resiliency, generally lower that twenty five (25) percent, and more desirably between two (2) and ten (10) percent.
The combination of the lesser “rocker” of the boot described, together with the “rocker” attachment of this invention and the softer deep gel pad gives the maximum flexibility for a horse to shift the weight and pressure points of its stance to find the most comfortable and least damaging position. This combination of a boot/pad/rocker attachment is an important embodiment of this invention.
In another aspect the invention is a kit for providing a rocker attachment to the underside of an equine boot comprising a one or two piece attachment (as described above) shaped to allow the boot to rotate forward or back having a break-over point within two (2) inches of the centerline, front to back, of the sole of the boot, specially adapted to fit the boot sole to which it is to be secured and a means of securing the attachment to the boot sole. The rocker will generally patterned to mate with the patterned on the boot sole on which it is to be used. If a spacer is provided, it, rather than the rocker, will be so patterned. The rocker and/or spacer may also be slotted as described above. The attachment means may be adhesive or mechanical such as the screw/nut combination (14) as illustrated in the Figures. The kit will contain the attachment and securing means packaged for convenience. The user will generally specify the boot by name or description and an attachment, optionally with instructions, to fit the boot can be supplied. Since there are thousands of boots by type, design and size, many of the attachments will be custom made to order.
In the foregoing specification, the invention has been described with reference to specific embodiments thereof. It will, however, be evident that various modifications and changes can be made thereto without departing from the broader spirit and scope of the invention as set forth in the appended claims. The specification and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive sense. Therefore, the scope of the invention should be limited only by the appended claims.
This application is a continuation application of application Ser. No. 12/882,352, filed Sep. 15, 2010 and claims benefit of Provisional Application Ser. No. 61/244,341 filed Sep. 21, 2010.
Number | Date | Country | |
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Parent | 12882352 | Sep 2010 | US |
Child | 14303246 | US |