Suspensory Break Down!

The suspensory ligament has been significantly stretched and strained, resulting in the "dropped fetlock" conformation seen below. The suspensory ligament (blue structure in drawing below) originates just below the hock in the hind limbs and the carpus in the forelimbs. The ligament splits into a medial (inside) and lateral (outside) suspensory branch. The split occurs approximately half way down the metatarsus. Each suspensory branch inserts on a sesamoid bone at the level of the fetlock and play a role in "suspending" the fetlock. For the fetlock to drop, the suspensory branch and body have been strained and maybe even ruptured. For definitive diagnosis, an ultrasound exam is performed that will evaluate the entire suspensory ligament. If the process is slow (months to years), it may result in reduced performance and low grade lameness. However, if sudden, significant lameness is associated with the limb or limbs affected. Unfortunately, this is a progressive condition that will ultimately result in retirement of the horse and may be life-threatening. Management of this condition includes reduced exercise, daily ice therapy, corrective shoeing, and daily pain management. This condition carries a poor prognosis for return to work and a guarded prognosis for over-all soundness.

The blue structure depicts the suspensory ligament in the forelimb. Note the upper region is one structure (body) which then splits into two branches.

These are known as "fish tail" shoes and are quite effective in reducing the strain on the suspensory ligaments. For obvious reasons, this type of shoe, with significant heel extension, can only be used in the hind limbs.