Decerebrate posture is an abnormal posturing exemplified by rigid extension of the arms with internal rotation, extension of the legs with internal rotation and downward pointing of the toes, and retraction (backward arching) of the head due to a severe injury to the brain at the level of the brainstem or diffuse cortical dysfunction.
Opisthotonos may accompany decerebrate posture in severe cases.
Usually, decerebrate posture indicates deterioration of the structures of the nervous system, particularly deterioration of 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, or a person can have decorticate posture on one side and decerebrate posture on the other.
Cerebral infarction (stroke)
Primary brain tumor
Secondary brain tumor
Increased intracranial pressure from any cause
Brain stem tumor
Conditions associated with decerebrate posture require immediate hospital treatment.
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:
CT or MRI of the head