Expert Exchange

Martha Olivo on the Bars and Navicular Syndrome

Q: What do the bars have to do with navicular syndrome?

A: Bars, when properly maintained, provide internal support to the hoof. Too much rigidity - excess bar or inflexible/ shod hooves - can interfere with the ability of the bars to do their job. Their function is to drop and enable the hoof to expand. As the hoof expands, the bars also provide traction. They are also the "snap back" mechanism of the hoof. High heels and high bars impair circulation by limiting the pumping action, thereby reducing the effective flow of blood. High bars also pinch and inhibit the blood supply to the bar corium above them, causing pain - navicular syndrome or caudal (heel) pain. Laid-over bars bruise the sole they cover, and also restrict blood flow into that part of the sole. This disallows healthy sole tissue to form (atrophy). They also compress the frog from side to side. High bars and high heels promote poor coffin bone development through lateral, or side-to-side, compression because as the heels grow longer and the bars become higher, the back of the hoof contracts, followed by the contraction of the whole hoof. The coffin bone itself becomes squeezed and deformed.

The navicular bone helps form the coffin bone/short pastern joint. It lies between the "wings" of the coffin bone. There is both a vein and an artery that run between the navicular bone and the coffin bone. The function of the navicular bone is to act as a valve for letting blood in and out. When the coffin bone becomes laterally compressed, the valve action of the navicular bone, which is naturally flexible in the (healthy) joint, is increasingly impaired and can be destroyed. Heel pain left untended or masked by shoes accelerates the deterioration, until the horse becomes too impaired to respond to conventional treatment. The only real relief is the restoration of the proper hoof form and causing the horse to become more active.

The bars are naturally worn down in the wild horse. In domesticity the wear is much less, and we need to keep the bars in check more. The compensation for domestication is proper trimming of the horses' hooves.

About the author:
Martha Olivo was a farrier for 25 years before hanging up her hammer and committing herself to the Whole Horse Trim™. The Whole Horse Trim™ is a physiologically correct hoof trim that duplicates the parameters found in feral equine hooves. As an accomplished hoof care clinician, Martha currently tours the US holding clinics that help horse owners, farriers and veterinarians understand the benefits of High Performance Barefootedness. Martha is a Strasser Certified Hoofcare Specialist and founder of United Horsemanship, a membership organization committed to the application of natural equine care.
United Horsemanship is a growing company dedicated to advocacy, natural horsemanship and “helping horsemen become better horsemen.” With her business partner, Tara Felder, Martha networks to support and educate people involved in the natural horse movement. Although United Horsemanship focuses on the care of horses’ feet, it isn’t just about trimming feet. It is a solidarity movement and a nationwide, for-profit membership organization that was born out of love and dedication to horses.
Committed to their company’s vision – “to form a commonwealth of support, education, advocacy and information among those individuals and organizations who regard natural horse care as a sensible, humane and preferable way to initiate and sustain optimal health and well being in horses,” Martha, Tara and a team of enthusiastic helpers work tirelessly to make United Horsemanship a self-supporting organization. For Martha’s clinic schedule, to schedule a clinic and to learn more about United Horsemanship, log on to their website at To schedule a clinic, call (360) 647-7503 or drop an email to

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