Today’s horses are much more prone to flat feet. Learn why, and what you can do about it.
When a foal is born, his coffin bone is high in the hoof capsule. The extensor process of the coffin bone is in line with, or slightly above, the coronet band. And the connection between the epidermal and dermal lamina is tightly connected.
Understanding Hoof Anatomy and Function
This natural secure attachment holds the internal structures of the hoof in place where they are meant to be – high up inside the hoof capsule, creating a bowl or concaved shape on the sole. This solar concavity occurs naturally in a healthy, well connected hoof and represents correct anatomy. The coffin bone is not flat, but instead has an arch to it. The external structure of the hoof mimics the internal structure. As the horse grows and develops, this tight connection remains strong and intact unless there a toxic insult to the horse’s system that results in laminitis.
When the hoof makes contact with the ground, it spreads and flexes, thereby absorbing the impact as the skeletal structure descends slightly within the hoof capsule under the horse’s weight. The sole flexes downward slightly until the bars and frog come into contact with the ground. The solar concavity allows the skeletal structure to move within the hoof capsule as the hoof expands and contracts during weight bearing and lift off phases. The concavity appears to create a suction cup that acts like a vacuum, helping to stabilize the horse in movement. I experienced this amazing hoof function when our barefoot racehorse got loose from the farm during an ice storm. She ran full speed up the road and turned 90º on sheer ice with no problem at all. She was in full control. Had she been wearing metal shoes, I doubt she would have been able to make the turn without falling.
Flat Feet and Today’s Horses
So why do we see so many flat-footed horses? Thanks to the research of Dr. Chris Pollitt and his team at Queensland University in Australia, we now understand the process that disconnects the internal dermal lamina (coffin bone) from the external epidermal lamina and hoof capsule. Every time a horse experiences a toxic insult to his system, the lamellar connection is compromised and weakened, causing the internal structure to sink. These repeated toxic hits may be in the form of an incorrect and unbalanced diet with too much sugar or fructans (grass and grain overload), mineral imbalances, inoculations, chemical wormers and stress/hormones.
Horses were never designed to digest large amounts of non-structural carbohydrates. Since they do not have enough amylase enzyme to digest large amounts of sugar, starch or fructans, these substances end up being dumped into the hind gut where they kill off the good bacteria, generating lactic acid which in turn causes lesions. The bad bacteria mass produce but die off quickly, resulting in endotoxins. Those toxins then go through the lesions into the bloodstream and directly to the lamina of the hoof, resulting in inflammation and separation.
A Compromised Support System
Further to this insult, we add peripheral loading. Horses were never meant to carry their weight entirely on the lamina. Metal shoes that do not support the frog and sole, or improper trimming, suspend the horse on the wall only, pulling the epidermal and dermal lamina away from each other and allowing the skeletal structure to migrate further down the hoof capsule, thereby flattening or pushing the sole out. The entire hoof, including the walls, bars, digital cushion, frog and sole, were all intended to work together and support the horse and internal structures.
If the horse has a weak caudal heel or a painful infection in the back of the hoof/frog, he will be forced to land on the toe first. This sets him up for all sorts of pathologies (i.e. navicular) and quickens the descent of the internal skeletal structure to the bottom of the hoof capsule.
Constant paring of the horse’s sole, toe callus and bars compromises the integrity of the entire hoof, again allowing for further descent of an already weak attachment to the internal structures. Decreased circulation caused by inflammation, reduced hoof function, improper hoof mechanism and overall inadequate movement, all cause weakening of the lamina. The end result – a flat-footed horse that will eventually become increasingly lame, with the possibility of irreversible damage to the internal foot as well as a crushed sole corium.
Reversing and Preventing Damage
So what can we do to prevent or reverse the distal descent of the hoof? Lots!
1. If you suspect your horse is compromised, ask your vet to take lateral x-rays of all four feet. It is important that the dorsal wall be marked with a metal stripe from the top of the hairline to the toe, in order to determine how far the internal structure has descended in the capsule. It also helps to place a marker at the apex of the frog to determine sole thickness.
2. Change his feed to the more natural native diet horses evolved on. They were never designed by nature to consume the large amounts of sugars and carbohydrates that modern domesticated horses consume. Have your hay analyzed for sugar and protein levels, micro and macro minerals. Then find or have a mineral supplement made that balances to your hay. More individuals and companies are sprouting up that understand the science behind this and who work with the NRC in balancing minerals to forage. High performance horses will require a more specialized and individualized diet, but they don’t necessarily require the added sugars and starch, so start by getting your hay/forage analyzed first.
3. Finally, get your horse out of the stall or small pen and get him moving. Movement is critical to the soundness of not only a barefoot performance horse, but all horses. Jamie Jackson’s Paddock Paradise concept, which simulates a more natural habitat, is easy to put into place and a sure way to get your horse moving. During his transition out of shoes, or to speed healing, it is important to use boots with pads to encourage sound and correct movement. It is also important to employ well-educated hoof care professionals to ensure correct trimming and rehabilitation methods.
References: Dr. Chris Pollitt, Dr. Robert Bowker, Dr. Eleanor Kellon, Jamie Jackson, Pete Ramey
Anne Riddell is an AHA Certified Natural Hoof Care Practitioner. BareFootHorseCanada.com