The suspensory ligament (SL) ties into the top of the cannon bone, just below and behind the carpus in the front limb and the hock in the hind limb. The structure runs down the back of the cannon bone, between the two splint bones. Two-thirds of the way down the cannon, it splits into inside and outside branches that attach to the sesamoid bones at the fetlock. Fibers pass on as the extensor branches to blend into the extensor tendons.

The SL is a critical structure for the sling function of the fetlock joint. Unfortunately it is a common site for the development of lameness conditions. "Body" injuries refer to injury to the midsection of the SL, called the body.

SL body injuries are more common in race horses and jumpers than horses engaged in other disciplines. That said, these injuries can happen to any horse. Typically, noticeable swelling in rear of the central cannon area is present and often there is pain to pressure over the swollen area. There is moderate to severe lameness.

Like other SL injuries, these take many months of exercise restriction to heal to a point that a horse can be returned to work. Depending upon the specifics of the injury, these injuries may recur.

Diagnosis of these injuries is made through clinical lameness exam and especially through ultrasound evaluation. In more subtle cases, nerve blocking is required to define the region. Ultrasound confirms and details the severity and characteristics of the injury.

There is a wide variety of treatment approaches available today, but the cornerstone remains rest, time and graded return to exercise.