What's the noun for tetanically? Here's the word you're looking for.
tetanus
(pathology, countable) A serious and often fatal disease caused by the infection of an open wound with the anaerobicbacterium Clostridium tetani, found in soil and the intestines and faeces of animals.
(physiology) A state of muscle tension caused by sustained contraction arising from a rapid series of nerve impulses which do not allow the muscle to relax.