It might not look like much, but run under heels (underslung) place excessive strain on your horses muscular and skeletal structures. This is an all too common, and often unnoticed pathology that is the result of excessive growth, and/or unnatural or poor trimming practices.
How does this affect my horse?
Most horse owners don't appreciate the damage that run under heels have on both their horses hooves, and body.
There are two common causes for this pathology to develop. Neglect, and poor trimming. I should be clear that it is never the intention of either a trimmer or a farrier to create this condition. However, if certain areas of the hoof are neglected, or a trim performed incorrectly even the most well meaning hoofcare practitioner can inadvertently create this condition.
The run under heel pushes the entire hoof, muscular and skeletal structure out of alignment. Placing excessive strain on the connective tissues, veins and arteries. Which in turn creates a roll on affect of various health problems. The longer this condition remains, and the more pronounced it becomes, the deeper and more lasting the damage to the internal systems.
Run under heels are known to cause quarter and heel cracks, damage to the deep digital flexor tendon, pedal and navicular bone degeneration, arterial damage, coffin bone damage, bruised heels, and hoof contraction.
Run under heels are often accompanied by long toes, this results in the hoof being pulled away from the coffin bone, leading to a stretched white line and abscesses. As this happens, the coffin bone begins to rotate, further unbalancing the horse.
As this condition continues, the digital cushion and lateral cartilages at the back of the hoof become weak. Without this protection, concussive force increases with each footfall, damaging the skeletal structure of the horse. If the coffin bone begins to lower, the sole will become thin, and create bruising and pain.
Toe first landings are a classic symptom of run under heels, which leads to even further damage of the internal hoof and skeletal structures of your horse.
How can I recognize it?
Once you know how to recognize an underrun heel, its impossible to miss. Yet this condition is now so common among domestic horses its no longer seen as abnormal, or it is not seen as a condition to be concerned about.
Look at your horses hoof from the side, preferably close to ground level. Taking note of the toe length, where the heel touches the ground, and the angle of the heel. If the toe looks too long, the heel too steep or the weight bearing platform look too far forward, they probably are.
Another test can be to imagine a vertical line running from the point of ground contact and see if it would pass through the pasterns and knee. If not, chances are the hoof is out of alignment with the rest of the skeletal system and your horse has run under heels.
You may find this test helpful.
How can I help to see this healed?
Time, patience and proper hoofcare are the only way a horse suffering from run under heels will recover.
Depending on the severity of this pathology the time frame can range from a single trim, to a long road towards rehabiliation. The recovery time is also heavily dependant on whether there has been internal damage caused by this condition. Damaged arteries, bruised tissue, hoof contraction, they all take time to heal.
How can I make sure this doesn't happen again?
As a horse owner you need to understand recovery does not happen overnight, and in some cases rehabilitation can be a long journey. The best thing you can do to help your horse is commit to their recovery.
Find a reputable barefoot trimmer and stick to the trim schedule (3-5 weeks max), it is your commitment to the hoofcare program and the advice of your NHC professional that will determine how fast, and well hoof function is restored.