The great thing about technological advances is that they provide new perpectives on old problems. Magnetic resonance imaging (MRI), for instance, has given equine veterinarians an improved vantage point for examining the underlying disease process in navicular syndrome cases. Historically, the term navicular syndrome referred to lameness resulting from pain in the podotrochlear apparatus in the back of the foot that includes the navicular bone, bursa (sac cushioning the navicular bone from the deep digital flexor tendon), supportive ligaments, and deep digital flexor tendon.

"Everybody used to think that navicular disease meant the problem related to degeneration in the bone and surrounding structures. That’s because on radiographs all we could see was the bone," explains Robert Schneider, DVM, Dipl. ACVS, professor and equine orthopedic surgeon at Washington State University’s College of Veterinary Medicine.

Veterinarians began recognizing, however, that this process involves more than just the navicular bone. The lameness that started out being called "navicular disease" was renamed "navicular syndrome" and later called "caudal heel syndrome."

"Even still, there were a variety of treatment failures and opinions about what and why things happen and how and why to treat this ‘syndrome,’ including various shoeing strategies," says Stuart Shoemaker, DVM, Dipl. ACVS, owner of Idaho Equine Hospital, in Nampa. "This indicated that there was little understanding about what was going on within the equine foot." The modality that revolutionized Shoemaker’s understanding of this foot lameness was MRI