LIGAMENTS NA.qxd:Jerkins feature.qxd
6/4/09
23:14
Page 2
LIGAMENT INJURIES
LIGAMENT INJURIES By James Tate BVMS MRCVS
Ligament injuries have led to the retirement of many of horseracing’s great heroes. The list of equine superstars who were forced into quitting the track include Champion two-year-old male of 2002, Vindication; the ever-popular grey Evening Attire; Champion older female of 2006 Fleet Indian; as well as Grade One winners Heatseeker, Zaftig (below) and Dance Smartly. Ligament injuries do not always lead to retirement but they are serious and must always be treated with extreme caution.
A
LIGAMENT is a tough band of fibrous tissue that connects bones or cartilages. There are approximately one hundred different types of ligament in the horse but a select few cause equine veterinarians problems time and time again. These ligaments are anatomically designed to be tough and relatively inelastic; however, the side-effect of this is that they do not heal well from injury and as a result have disappointing recovery rates. If the horse is fortunate, the injury may become apparent at a relatively early stage when it is no more than a simple inflammation or ‘desmitis.’ However, if the horse is not so fortunate, it may suffer from a ligament tear, which is a very serious injury. Given the large variety of ligaments in the horse it is difficult to group them together, but ligament injuries do tend to behave in similar ways. Diagnosis is usually straightforward, as an affected ligament is hot, swollen and painful and the difference in diagnosis only comes from the position of the ligament. For example, a suspensory ligament injury is usually obvious for all to see as its position makes it easy to feel and an ultrasound scan is only required to establish the severity of the injury and to monitor healing. However, diagnosis of a joint ligament injury is more challenging and relies either on an assumption or a good ultrasonographer to pinpoint the affected area. Suspensory Ligament Injuries The suspensory ligament is perhaps the best-known ligament of the horse. Strictly speaking, this ligament is the equivalent of an interosseus muscle found in other animals, however, in the horse it is composed of tough fibers and there is only a small amount of muscle tissue present. It originates from the back of the knee (or hock in the hind leg) and runs down the back of the cannon bone until splitting into two suspensory branches in the lower third of the cannon. Each branch then has a portion that attaches to a sesamoid bone
ISSUE 12 TRAINERMAGAZINE.com 33