Definition of Opisthotonos:

Opisthotonos is a condition of abnormal posturing that involves rigidity and severe arching of the back, with the head thrown backward. If a person with opisthotonos were laid on his or her back, only the back of the head and the heels would touch the supporting surface.

Considerations:

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.

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:

• Growth hormone deficiency (occasionally)
• Arnold-Chiari syndrome
• Brain tumor
• Gaucher disease
• Glutaric aciduria and organic acidemias
• Krabbe Disease
• Meningitis
• Seizures
• Severe head injury
• Stiff-person syndrome
• Subarachnoid hemorrhage
• Tetanus

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