Risus sardonicus

The Risus sardonicus (Latin for sardonic laughter, often inaccurately called " devil grin " translated) is a symptom of infection with Clostridium tetani.

These bacteria cause tetanus, the tetanus. Due to the muscle tension to pull together the facial muscles and cause a sardonic grin expression, the Risus sardonicus. That grin can not solve the patient.

Risus sardonicus also occurs at a poisoning with strychnine.