Stringhalt is a gait abnormality characterized by exaggerated upward flexion of the hind-limb. It may occur one-sided or bilateral and all degrees of hyper-flexion can be seen. The exact cause is unknown, but degenerative lesions on long nerves of the hind limb have been identified in affected horses, resulting in the typical gait abnormality.
Australian Stringhalt is associated with the ingestion of flatweed and dandelion. Other environmental factors or the growth of fungus on these particular weeds are suspected to be involved to cause the condition. Stringhalt often affects multiple horses in one region and often affects both hind limbs. Commonly it occurs after a break in dry weather usually in late summer or autumn.
Horses with Stringhalt often recover spontaneously when taken away from the weeds. Unfortunately Stringhalt can be a progressive condition with the gait abnormality becoming so severe that euthanasia is warranted.
Mild Stringhalt may be intermittent, in some cases is seen only in the first few steps and often the signs are less intense or even absent during warmer weather. Further in mild cases the condition is regarded as unsoundness, but may not hinder the horse’s ability to work, it may be just unsuitable for some equestrian disciplines.
Stringhalt is diagnosed is based on clinical signs.
When stringhalt is suspected removal to another paddock may be all that is required.
Supplementation with thiamine (Vitamin B1), Vitamin E and magnesium is recommended. In chronic cases, tenectomy – cut tendon- surgery of a specific tendon has given some results, however improvement may not be evident until a few weeks after surgery and not all cases respond. Prevention is the best treatment. Check your paddock regularly for weeds.
If you suspect your horse being affected by stringhalt, please let us know and Canberra Equine Hospital is happy to help you and your horse.
References: Veterinary Merk Manual, Plants Poisonous to Horses – An Australian Field Guide, Australian stringhalt by Dr. John Kohnke; Photos: © 2008 Zoya Akulova, Slichter 2009, wickimedia.org, vetstream.com;