Since its inception in the 1930s, the inaugural patent in 1974, and the successful construction of the world’s first whole-body scanner by 1977, magnetic resonance imaging (MRI) has become an indomitable tool in both human and equine medicine. Today, equine practitioners use MRI extensively to help diagnose even the most subtle lameness causes.

“One region of the horse’s body that is a common site for injury is the lower (distal) aspect of the suspensory ligament near the fetlock joint,” explained Alexander Daniel, MRCVS, from Colorado State University’s Veterinary Teaching Hospital, during the 2012 American Association of Equine Practitioners’ (AAEP) convention, held Dec. 1-5 in Anaheim, Calif.

The suspensory ligament originates near the top of the cannon bone at the back of the carpus (knee) and hock, travels down the back of the leg, and splits into two branches—the medial and lateral branches—before each branch inserts onto a sesamoid bone.

“It is known that injury to the suspensory ligament near the fetlock can occur either in isolation or combination with injury to the one or both sesamoid bones,” Daniel said