Assessment of bilateral infra-orbital nerve blockade and bilateral infra-orbital neurectomy in the investigation and treatment of idiopathic headshaking.

This research article discusses how the implementation of bilateral infra-orbital nerve blocking and bilaterial infra-orbital neurectomy can potentially aid in the treatment and ongoing investigation of idiopathic headshaking in horses. The article investigates this condition, its causes, the treatment options available, and their effectiveness in treating it.

Idiopathic Headshaking in Horses

• Idiopathic headshaking is a condition in horses where the horse shakes its head excessively and frequently, without any apparent reasons or stimuli. This behavior presents particular challenges for horse riders as it makes the horse difficult or even dangerous to ride.
• Despite being a recognized issue, it is still poorly understood and often remains undiagnosed after comprehensive investigations. In a review of 100 cases, only 10 were found to have potential causes for this condition.
• Potential causes for this behavior in horses range from ear mites, infections, injuries, allergies, stereotypic behavior, partial asphyxia, to various types of neuropathy.

Possible Treatments

• Treatment for headshaking where no precise cause has been found or suspected is generally unfruitful. Temporary solutions, such as covering the muzzle, have shown to reduce the severity in some cases, but the effect is only temporary and partially successful.
• Medication to modulate allergic rhinitis, a potential cause of headshaking, has proven ineffective. However, inhaled corticosteroids have been found to be partially effective in some cases.
• Common treatments, such as infra-orbital neurectomy, have been performed for many years, but there have been few reports of its effectiveness.

Importance of Infra-orbital Nerve

• The infra-orbital nerve, part of the maxillary branch of the trigeminal nerve, supplies sensory innervation to the upper lip, cheek, nostril, and gums. Understanding its behavior can provide insights into headshaking.
• Earlier studies have shown that neurectomy provided sustained relief from headshaking in a few horses, but further surgical procedures were required in some.
• Blocking the infra-orbital nerve, or neurectomy, aids in diagnosing irritations in areas supplied by this nerve. This diagnostic tool can be used to evaluate the effectiveness of infra-orbital neurectomy in treating headshaking.

Objective of the Study

• The focus of this research is to review the outcomes of using bilateral infra-orbital nerve blocks and neurectomies in horses affected by idiopathic headshaker syndrome. It also aims to study the correlation between the results of these nerve blocks and neurectomies.