Hoof growth is influenced by several factors. These include but are not limited to season, age, gender, breed, metabolic rate, trimming and shoeing, and nutrition. Average hoof growth for these reasons has a wide range but for a mature horse, this is around 5.7-8.4 mm (2 ¼ – 3 ⁵/₁₆ in)/month. Most research has focused on the effects of nutrition on hoof growth and quality, with adequate caloric intake and biotin supplementation being important factors for proper hoof growth.
 End of first shoeing cycle with Twin™ Shoes (1 x 4 weeks). Notice the more oval shaped hoof (length > width, often seen when shod with a traditional one-piece shoe) with a long toe and relative narrow heels! |
 Start of fourth shoeing cycle with Twin™ Shoes (3 x 4 weeks). Notice that the toe has become shorter, and the heels have become wider, creating a more rounded (normal) hoof. |
The exact mechanism(s) of hoof growth itself is still unknown, but it is fair to say that increased blood supply, metabolic rate (exercise), cellular proliferation and differentiation by mechanical stimulation are all potential mechanisms involved in hoof growth. Two of these factors (blood supply and mechanical stimulation) are positively affected by the Twin™ Shoe and the third one is function of movement. As such, the saying “movement is life” definitely applies the horse’s feet as well.
The mechanics of the circulation of blood through the horse feet are closely associated with the ability of the heels to expand and contract and the Twin™ Shoe is the only research proven shoe in todays market that allows this unrestricted heel movement.
The hoof quality and shape is preserved by the Twin™ Shoe due to the fact that the Twin™ Shoe moves with the hoof. As such there is no excessive wear of the heels in comparison with the rest of the hoof wall as there is minimal friction between the Twin™ Shoe and the hoof wall. As a result, the dorsal hoof angle and solar angle are maintained between shoeing cycles, allowing for consistent biomechanics and minimising stress on the structures in the back of the foot and distal limb. Moreover, as the Twin™ Shoe allows for mechanical stimulation through a normal functioning hoof mechanism we can make the hoof stronger through exercise. Just like a muscle, a hoof is capable to adapt to new stimulations and get stronger by continues exercise as long as hoof movement is not restricted.
 Limited or no Heel Wear withTwin™ Shoes |
 Significant Heel Wear with traditional shoes |
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| The picture above is from a hoof shod with a closed Twin™ shoe (comparable to a traditional shoe, i.e. not split at toe). When shod, the dorsal hoof wall angle (DHWA) was 52.15°. The picture below shows the same hoof at end of shoeing cycle (after 6 weeks), due to the wear at the heels, the DHWA was reduced to 50.14°. This is in line with the typical average decrease in DHWA of +/- 0.79° per 2 weeks seen in horses shod with traditional shoes. This affects the biomechanics of the distal limb and the stresses on the hoof capsule (and it’s associated internal structures) in a negative way. | The picture above is from the other hoof of the same horse shod with a Twin™ Shoe (shoe split at toe). When shod, the DHWA was 53.32°. The picture below shows the same hoof at end of shoeing cycle (after 6 weeks), as the Twin™ shoe (when split at the toe) moves with the hoof, there is less wear of the heels over the shoe and the DHWA (53.35°) stays more or less the same throughout the shoeing interval as intended by the farrier. |
As the Twin™ Shoe moves with the hoof, it does not confine the hoof. As such we see minimal focal stress and/or hoof capsule distortions, and there is more equal wear between heels and toe preserving the dorsal hoof and solar angle between shoeing cycles.
Because the Twin™ Shoe allows normal heel movement (does not restrict the hoof mechanism), blood circulation to and in the hoof is maintained similar to barefoot horses and improved compared to traditional horses. This, combined with proper cellular proliferation and differentiation from mechanical stimulation, allows for an increased hoof growth rate compared to a traditional shoe.