Stringhalt

Description

Stringhalt is a gait problem that may affect one or both hind legs. This rare form of lameness, which causes the horse to lift its hind legs higher and more rapidly than usual when it is moving, varies from a mild muscle spasm to movements so severe that the horse actually strikes the abdomen with the forward-moving fetlocks.

Sometimes, spastic movement is also seen in the front legs with toe scuffing and a stumbling movement. In severe cases, horses may not be able to stand. Ordinarily, the horse does not appear to be in pain, yet the lack of control of the hind legs makes riding difficult.

Symptoms

• Uneven gait, especially in hind limbs
• Upward jerk of hind leg combined with involuntary flexion of the hock as horse moves forward
• Toe scuffing and stumbling movement of front limbs
• Inability to stand

Causes

So far, no definite cause has been established. Some cases follow trauma to the tendon and most scientists believe possible causes of stringhalt include certain neuromuscular conditions, although no definite determination of specific relationships have been made. In horses with bilateral stringhalt, a central location of nerve damage, either in the spinal cord or brain, is suspected.

Certain pasture and climate conditions have been linked to outbreaks, but they are sporadic. Cold weather seems to increase symptoms and poor pastures that have weeds and are going through drought conditions may also play a role.

Prevention

Since no definite cause or causes have been established, ways of preventing stringhalt have not been realized. Good horse management with high quality feed and appropriate medical response when legs are affected by trauma may help prevent some cases of stringhalt.

Treatment

Treatment of stringhalt is usually surgical and involves removing a portion of the lateral digital extensor muscle and tendon to restore a more normal gait. If adhesions have developed at the site, they will need to be freed. Some horses with stringhalt recover spontaneously when removed from pasture.