Abstract
Jaw clonus, a fascinating, yet uncommon clinical sign, is suggestive of supranuclear lesions of the trigeminal nerve. It has previously been reported in association with amyotrophic lateral sclerosis. Hereby, we report an index case of jaw clonus in a patient of neuromyelitis optica spectrum disorder with subsequent osmotic demyelination syndrome with pseudobulbar palsy due to the involvement of pontine corticobulbar fibres.