Stringhalt is an involuntary upward flexion of the hock that occurs as the horse is walking. Usually this occurs every step of the walk and may also effect the trot intermittently but only rarely the canter. In some cases, particularly the toxic form, the condition often is bilateral and the front limbs may be effected. It happens as the horse is lifting the hind foot off the ground the leg motions continues in an end exaggerated upward motion, to the degree that the limb may slap the belly. Stringhalt must be differentiated from many diseases that cause abnormal upward flexion of the hindlimb. This article addresses the clinical signs, diagnosis and differential diagnosis, causes, treatment and prognosis of horses and equines with stringhalt and stringhalt like diseases.

Frequently, stringhalt has an acute onset with no previous history of problems. The disease is usually progressive. Stringhalt is a gait abnormality characterized by an involuntary hyperflexion, a sudden jerk upward, of the rear leg that occurs as the horse moves forward or backward. It looks like a rapid upward jerk of the leg as the leg is brought forward. On careful inspection often the affected leg is both brought up and in underneath the horse. It can range in severity as relatively mild, evidenced only as a slight "hitch" as the horse moves forward, or it can be severe: a radical "jerk" where the leg will strike the abdomen. Most horses will show signs at every step of the walk, others will "spasm" occasionally.

The stringhalt often lessens during the trot and usually disappears at the canter. The condition will almost always be more obvious when the horse is backing up or turning, and it will almost always be more exaggerated when the horse is first moved from a resting position.

Stringhalt can occur in as an epidemic in a herd of horses, believed to be due to consumption of a toxic plant resembling dandelion. This form usually effects both hind limbs and in some cases can effect the front limbs also. For more see Causes below.

Other diseases can cause Stringhalt and other abnormal hind limb gait abnormalities resemble Stringhalt so a careful full exam, survey of the forages and pasture and, in some cases, blood chemistries is important in the evaluation of Stringhalt.