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Related to risus sardonicus: tetanus
risus sardo´nicus a grinning expression produced by spasm of the facial muscles; seen in tetanus and certain types of poisoning.
ri·sus ca·ni·nus(rī'sŭs kā-nī'nŭs),
the semblance of a grin caused by facial spasm, seen especially in tetanus but also in some kinds of poisoning.
[L. risus, laugh + caninus, doglike]
Etymology: L, laughter; Gk, sardonius, mocking
a wry masklike grin caused by spasm of the facial muscles, as seen in tetanus.
Prognosis Up to 90% mortality in the unvaccinated and/or susceptible population—e.g., narcotic addicts
risus sardonicusA fixed 'sarcastic' grimace and anxious expression with drawing up of the eyebrows and corners of the mouth due to spasms of the masseter and other facial muscles, accompanied by rigidity of neck and trunk muscles and arching of back; the RS is seen in generalized tetanus, and caused by a neurotoxin produced by.Clostridium tetani, a soil contaminant with a 7-10 day incubation Prognosis Up to 90% mortality in the unvaccinated/susceptible–eg, narcotic addicts
risus sardonicusA characteristic facial expression, as of a sardonic grin, caused by spasm of the muscles of the forehead and the corners of the mouth in acute TETANUS.
a grinning expression produced by spasm of the facial muscles, typical of tetanus in humans. The term is also applied to dogs with tetanus in which the lips are drawn back by muscle spasms.