An epileptic spasm is a specific type of seizure seen in an epilepsy syndrome of infancy and childhood often called West Syndrome. These are more commonly called infantile spasms (IS) since they are seen most often in the first year of life. West Syndrome/IS is characterized by epileptic spasms, developmental problems, and a specific brain wave pattern on electroencephalography (EEG) testing called hypsarrhythmia. The onset is usually in the first year of life, typically between 4-8 months. The seizures often look like a sudden bending forward of the body with stiffening of the arms and legs lasting for 1-2 seconds; some children arch their backs as they extend their arms and legs. Spasms tend to occur upon awakening and often occur in multiple clusters and hundreds of seizures per day.

http://www.semanticweb.org/danielhier/ontologies/2019/3/untitled-ontology-57#infantile_spasms

http://www.semanticweb.org/danielhier/ontologies/2019/3/untitled-ontology-57/seizure