Q: Is it really navicular disease, or just tendonitis? Are they the same thing? If they are different, how can they be treated differently?

—Texas Farrier

A: The term “navicular disease” has lost a significant amount of credence over the past few years. The term “chronic heel pain” has come into vogue. This broader term for heel pain in the horse could include navicular bone inflammation, coffin joint arthritis, navicular bursitis, zero or negative palmar angle problems, deep flexor tendon and supporting ligament problems, etc.

The advent of magnetic resonance imaging (MRI) diagnostic use for the horse’s foot will open a new list of foot problems and require more and more data collection about how to treat these particular horses, both medically and mechanically.

Navicular disease implies some radiographic diagnosis along with the clinical findings. However, tendonitis would require some ultrasound or MRI findings along with the clinical findings. Thus tendonitis is now extremely difficult to diagnose on an everyday basis, and minimal studies have been done on tendon and ligament inflammation.

Currently, any chronic heal pain could be treated in a few different medical and mechanical ways, but the difference between bone joint inflammation and tendon ligament inflammation is that a monitored, potentially prolonged rest period would be necessary for tendon and ligament inflammation.

—Richard Mansmann, VMD, PhD Chapel Hill, N.C .

A: Navicular disease (ND), now more frequently referred to as navicular syndrome (NS), has several etiologies. Tendonitis of the deep digital flexor (DDF), a primary injury or…