Equine neurologic examination in practice

A thorough neurologic examination is required when a horse shows signs of neurological disease or when it has to be confirmed that the horse is neurologically normal. The main purpose of the examination is to investigate whether there are neurological deficits. In addition, the identification of the primary cause and localization of the lesion should be attempted. A standardized head-to-tail approach helps to avoid overlooking important lesions. Therefore, the examination always starts with a thorough patient history, observation of the horse with special attention to mental state, behavior, posture and stance, and a clinical examination. Subsequently, the cranial nerves are tested by investigating, amongst others, the menace, light and palpebral responses. The neck, trunk, limbs and tail are examined for asymmetry or hypo-or hypersensitivity. Afterwards, the movements of the horse are inspected. Incoordination of the horse is accentuated during transitions, small circles and zig zag lines. However, the difference with orthopedic problems is not always easy to make. Especially horses in lateral recumbency present an extra challenge as recumbency itself may cause a change in responses. Further examinations are often necessary to confirm neurologic disease or to visualize a lesion. Blood examination (general, serology, virus isolation), liver or muscle biopsies, examination of cerebrospinal fluid and radiographs are feasible to perform in practice. In specialized hospitals, electro-diagnostic tests and advanced medical imaging (CT, M RI, scintigraphy) are available. By combining these techniques with the clinical neurologic examination, a (differential) diagnosis can be made.