Hoof care
The issue of hoof care is a subject of great debate. Corrective shoeing can be beneficial to horses suffering from navicular disease, although sometimes the effects are only temporary. Others believe that removing the shoes altogether is the best way to manage this disease, as it allows increased circulation to the hoof. People on both sides agree that proper hoof shape and angle are an important long-term management plan for a horse with navicular disease. As with laminitis, different horses may respond in different ways to a given technique, so the farrier, owner, and veterinarian should work as a team to formulate a plan and to adapt if the initial plan is not effective. People who choose to treat navicular disease through shoeing may use a shoe designed to lift and support the heels. This can sometimes be accomplished with a flat shoe and trimming alone. Wedge pads or wedged shoes are often used, but can amplify heel-related problems if present. Another strategy is to use a bar type shoe. Often, an egg-bar shoe, or straight bar shoe. Some horses benefit from shoes that change the breakover of their foot (like a rolled toe). With or without shoes, the hoof must be trimmed in such a way as to restore the balance and angle that may have been lost. Horses with long toe-low heel conformation need careful trimming to counter this. Horses with upright feet may need their heels lowered and a shoe that will allow their heels to spread.
Inflammation from strain of the impar ligament can decrease blood flow to and from the navicular bone, as the major blood vessels supplying the bone run up and down this area. If the ligament continues to be strained, it can thicken and permanently reduce blood flow to the navicular bone. Because veins are more easily compressed than arteries, blood flow to the bone would be less obstructed than blood flow from the bone. This would cause a buildup of pressure within the navicular bone. The navicular bone, in response to both the increased pressure and overall decreased blood supply, would absorb mineral from its center. Excess tension can also cause exostoses where the ligaments attach to the navicular bone, giving the bone a "canoe" shape. If tension is extreme, the ligaments may actually tear. Recent research has found correlations between "toe-first landing" of the hooves and navicular problems, due to excessive strain put on the deep digital flexor tendon, as a consequence of misalignment of the lower joints. Toe-first landing, usually seen as a consequence of navicular disease, may actually be a cause or at least a contributing factor to the onset of tendon inflammation and bone modifications. Toe-first landing is often caused by frog and heel overtrimming, long toes, and/or poor shoeing. Contributing factors
Conformation
Certain conformational defects may contribute to navicular syndrome, especially defects that promote concussion. These include upright pasterns, small feet, narrow and upright feet, significant downhill build (commonly seen in American Quarter Horses), and long toes with low heels (commonly seen in Thoroughbreds).