Delayed onset vagus nerve paralysis after occipital condyle fracture in a horse

Abstract

Occipital condylar fractures (OCFs) causing delayed onset lower cranial nerve paraly-sis (LCNPs) are rare. We present a 7-year-old Friesian horse with delayed onset dys-phagia caused by vagus nerve (CNX) paralysis and suspicion of glossopharyngealnerve (CNIX) paralysis developed several days after a minor head injury. Endoscopicexamination revealed right laryngeal hemiplegia and intermittent dorsal displacementof the soft palate. An area of submucosal hemorrhage and bulging was appreciatedover the dorsal aspect of the medial compartment of the right guttural pouch. Radio-logical examination of the proximal cervical region showed rotation of the atlas andthe presence of a large bone fragment dorsal to the guttural pouches. Occipital con-dyle fracture with delayed onset cranial nerve paralysis was diagnosed. Delayedonset cranial nerve paralysis causing dysphagia might be a distinguishable sign ofOCF in horses. Delayed onset dysphagia after head injury should prompt equine clini-cians to evaluate the condition of the atlanto-occipital articulation and skull base.