Opisthotonus

Opisthotonus is a severe, sustained muscle spasm in the neck, back, and limbs that causes the body to arch backwards. It usually develops suddenly and can last for several minutes. Symptoms may include rigid muscles, jerking or twitching movements, and difficulty breathing. It can be caused by a variety of medical conditions, including brain injury, stroke, and drug overdose. It can also be a sign of a serious medical emergency, such as meningitis or encephalitis.