Decerebrate posture is an abnormal body posture indicated by rigid extension of the arms and legs, downward pointing of the toes, and backward arching of the head. A severe injury to the brain at the level of the brainstem is the usual cause.

Opisthotonos (a severe muscle spasm of the neck and back) may accompany decerebrate posture in severe cases.

Usually, decerebrate posture indicates deterioration of the structures of the nervous system, particularly the upper brain stem.

Decerebrate posture occurs in many patterns. It can occur on one side, on both sides, or in just the arms. It may alternate with decorticate posture (abnormal posturing due to corticospinal tract injury), or a person can have decorticate posture on one side and decerebrate posture on the other.

• Cerebral infarction (stroke)
• Intracranial hemorrhage
• Primary brain tumor
• Secondary brain tumor
• Encephalopathy
• Head injury
• Increased intracranial pressure from any cause
• Brain stem tumor
• Hepatic encephalopathy

Conditions associated with decerebrate posture require immediate hospital treatment.

Abnormal posturing of any sort usually accompanies reduced consciousness. Anyone exhibiting an abnormal posture should be examined promptly by the health care provider.

In some conditions such as prolonged coma, these behaviors can persist for an extended period of time.

Emergency measures may begin immediately, including placement of an artificial airway (breathing tube) and assistance with breathing. You will likely be hospitalized in intensive care. Once you are stabilized, a medical history will be obtained from family members and a physical examination will be performed.

Medical history questions documenting decerebrate posture in detail may include:

• When did this behavior start?
• Is there a pattern to the occurrences?
• Is it always the same type of posture?
• Is there any significant medical history (such as a known head injury)?
• What other symptoms preceded or accompanied the abnormal posturing?

The physical examination will include a complete neurological assessment.

Diagnostic testing may include:

• Cerebral angiography
• CT or MRI of the head
• EEG
• ICP monitoring