Headshaking syndrome is an intermittent, apparently involuntary, movement of the horse’s head. It may occur at rest or at exercise. The signs may be so severe as to prevent the horse being ridden.
It is not an uncommon problem, and proves very frustrating to treat. It is thought to be due to pain in the sensory nerves supplying the face (trigeminal nerve).
Although some progress has been made towards both diagnosing and treating the condition in horses, the pathology of the disease remains unknown and further research is needed.
Caudal compression of the infraorbital nerve currently offers the best prognosis for a successful outcome compared with other treatments.
The procedure was developed by Veronica Roberts and colleagues at the University of Liverpool's Veterinary School. Now Clinical Fellow in Equine Medicine in the University of Bristol’s School of Veterinary Sciences, Roberts has received a grant from the British Neuropathological Society to investigate possible focal demyelination of the nerve as a cause of headshaking in horses.
Demyelination is the most common cause of trigeminal neuralgia in people, so the research team will look to see if it is involved in the equine condition. They will collaborate with Seth Love, Professor of Neuropathology at the University of Bristol's School of Clinical Sciences, as he has carried out work in this area in people.
To find a more effective treatment and to understand the disease, Dr Roberts is requesting that anyone who is considering euthanizing a horse due to headshaking to contact her for possible inclusion in her study.