“Navicular disease is very difficult to study, because you can’t reproduce it in a normal horse,” said Earl Gaughan, DVM, of Kansas State University’s College of Veterinary Medicine. “You can’t then work backward from the disease to find a cure. The pathogenesis for navicular syndrome remains unproven, but there are some common trends.”

He discussed many considerations in diagnosing the cause of heel lameness at the 15th annual Bluegrass Laminitis Symposium January 21-23, 2002, focusing primarily on identifying navicular syndrome.

These include:

• Small hooves relative to body size;
  
• Work with a torsional component (twisting forces on limbs);
  
• Unbalanced hooves; and
  
• Irregularly scheduled farrier care.

“Navicular” horses tend to have several common threads in their histories, including an apparent acute onset of lameness (often following a period of indeterminate poor performance), which can mimic proximal (high in the limb) lameness when viewed from the saddle that worsens with stops and turns and seems to shift from the left to the right forelimb (and vice versa). They also have a characteristically choppy stride, which results from the horse trying to land toe-first or flat (instead of the normal heel-first sequence)