Q: My 12-year-old Quarter Horse has started limping on his right front when asked to trot under saddle. He does this only occasionally, not consistently, and he is sound when running with the other horses in pasture.
My veterinarian observed him and concurred that he appears to be uncomfortable only at the trot. After further evaluation with x-rays and a nerve block, my veterinarian identified the problem as navicular syndrome and suggested heart-bar shoes and pads. I consulted with a second veterinarian to confirm this diagnosis. He agreed with the first veterinarian’s findings; however, he recommended that I find a “natural trim” farrier and avoid the shoes and pads. I want to provide the best care for my horse. What is the general consensus on treating early-onset navicular? —Dottie Young; Chester, South Carolina
A: “general consensus” on treating navicular syndrome is elusive, if not impossible, to find. Your best bet is to gather as much information as you can and make an informed decision based on your particular situation and level of trust in the veterinarian and farrier who will be helping your horse. To get you started, I can share my own thoughts.
Evidence suggests that, during the early stages of navicular syndrome, inflammation and pathological changes may occur in several areas of the foot, including various ligaments, tendons and even the coffin bone, in addition to the navicular bone. These tissues require considerable time to heal. I feel that the goal for trimming and managing a navicular horse is to
enable healing to progress within the affected tissues and the entire foot, as well as the whole body of the horse. Toward this end, I make two basic recommendations:
First, trim the hooves with the goal of gradually lowering the heels and actively engaging the frog with the ground surface. This process decreases the biomechanical stresses within the foot by increasing the surface area of loading—it’s analogous to changing from high heels into sneakers in people.
I prefer to “engage the frog with the ground” gradually over one to three trimmings because once the shoes are removed the horse may feel a change in sensation that is often perceived as discomfort. This effect generally lasts only a few days, but it is used to justify the traditional thinking about the need for shoeing. Instead, you can try hoof boots with pads or pasturing the horse on a very conformable surface, such as pea rock, during this period.
The foot is best trimmed every four to five weeks by a farrier who understands and embraces these goals. Trimming at such frequent intervals results in a more consistent interaction of the foot with the ground surface. (Longer intervals may allow the hoof wall to grow until it extends beyond the sole, which can alter the loading pattern on the foot and adversely affect other structures within it.) Once it’s on the ground, the frog should not be trimmed or even “neatened” because this will change the sensory feedback perceived by the horse and potentially alter his movements.
Second, keep the horse moving. I believe horses with navicular should not be confined to stalls, even if they appear sore in the early stages of treatment. Movement increases circulation in the foot, and the loading of each step encourages the structures within the foot to heal in ways that are more conducive to activity.
In other words, the foot must be used as it heals if it is to heal in a functional manner. Padded boots, conformable surfaces, occasional medications and “common sense” will go a long way toward helping the horse stay comfortable during this process.
Recovery will often take many months, rather than the days or few weeks you may have been promised with other courses of treatment. But, in my experience with these techniques, navicular syndrome is not a death sentence to your horse.
Robert Bowker, VMD, PhD
Michigan State University
East Lansing, Michigan