By Austin Edens, CJF
Shoeing with frog support has gained traction in the past few years with its primary benefit for caudal support of the hoof capsule. We have many tools at our disposal to combat caudal failure in the hoof capsule, such as heart bars, frog-support pads, DIM, pour-ins, etc. Anecdotally, I often observe an extra amount of hoof growth after applying these measures. This accelerated growth can be explained by the additional frog support increasing engagement of the venous plexus in the caudal region of the hoof.
Horses evolved with the frog as a weight-bearing structure. On a barefoot hoof, the frog synchronously engages the ground with the heels during the loading phase of the stride. One negative effect of shoeing horses with a regular shoe is that the frog of a shod hoof bears less weight and has less ground contact than its barefoot counterpart. For the vast majority of horses, this slight decrease in frog function has a negligible effect on the health of the foot. However, there is a substantial portion of the sport horse population that experience caudal collapse of the structures that are vital for nurturing blood flow in the venous plexus. These compromised feet can benefit from the additional frog and caudal support by increasing blood flow via the venous plexus and its supporting structures of the hoof capsule.
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PHOTO 1 – UNSHOD HOOF: The load of the bony column (red arrows) colliding with the ground reaction forces (green arrows), and creating outward pressure on the heels (yellow arrows) due to the increased hydraulic pressure of the caudal region. On a barefoot hoof, compression of the frog and digital cushion initiate simultaneously with the heels when contacting the ground, thus maximizing the hemodynamic function of the venous plexus.
PHOTO 2 – SHOD HOOF WITH A REGULAR SHOE: The load of the bony column (red arrows) shearing against the ground reaction forces (green arrows), and creating inward and forward pressure on the heels (yellow arrows) due to the higher GRF on the heels. There is a delayed and reduced GRF on the frog and digital cushion.
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PHOTO 3 – SHOD HOOF WITH A WELD-IN FROG PLATE: A weld-in frog plate on a Kerckhaert DF with FootPro™ DIM 20 is one of my go-tos for increasing caudal support and optimizing venous plexus function.
PHOTO 4 – SHOD HOOF WITH FROG SUPPORT (HEART BAR): This is the best of both worlds. The foot has the protection and support of a shod foot and the hemodynamic function of the venous plexus of a barefoot hoof.
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PHOTO 5 – CAUDAL CROSS-SECTION: Caudal cross-section view with digital cushion and collateral cartilages.
PHOTO 6 – LOADING FORCES ON AN UNSHOD FOOT: Caudal cross-section view of loading forces on an unshod foot. Compression of the frog and digital cushion push against the collateral cartilages to pump blood up through the venous plexus.
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PHOTO 7 – LOADING FORCES ON FOOT WITH A REGULAR SHOE: Caudal cross-section view of loading forces of a foot with a regular shoe. Some frog and digital cushion compression is lost due to less GRF on its palmar structures.
PHOTO 8 – LOADING FORCES ON A FOOT WITH A HEART BAR SHOE: Caudal cross-section view of loading forces of a foot with a heart bar shoe. Frog and digital cushion compression is restored on a shod foot with the addition of frog support (heart bar).
This article is from The Natural Angle Volume 19, Issue 2. For more Natural Angle articles and tips, click here.
