Definition of Opisthotonos:

Opisthotonos is a condition in which the body is held in an abnormal posture. It usually involves rigidity and severe arching of the back, with the head thrown backward. If a person with opisthotonos lays on his or her back, only the back of the head and the heels would touch the supporting surface.

See: Abnormal posturing

Considerations:

Opisthotonos is much more common in infants and children than in adults. It is also more exaggerated in infants and children because of their less mature nervous systems.

Common Causes:

Opisthotonos may occur in infants with meningitis, where it is a sign of irritation of the membranes surrounding the brain and spinal cord (meninges).

It may also occur as a sign of depressed brain function or injury to the nervous system.

Other causes may include:

• Brain tumor
• Growth hormone deficiency (occasionally)
• Glutaric aciduria and organic acidemias (forms of chemical poisoning)
• Krabbe Disease (disorder of metabolism)
• Meningitis
• Seizures
• Severe head injury
• Stiff-person syndrome (a condition that involves worsening rigidity and spasms)
• Subarachnoid hemorrhage (bleeding in the brain)
• Tetanus
• Arnold-Chiari syndrome (a brain structure problem)
• Gaucher disease (disorder of metabolism)

Drugs, particularly phenothiazines and other antipsychotic medications, can cause a side effect known as acute dystonic reaction. Opisthotonos may be part of this reaction.

In rare cases, infants born to women who drink large amounts of alcohol during pregnancy may have opisthotonus due to alcohol withdrawal.