Decerebrate posture is an abnormal body posture that involves the arms and legs being held straight out, the toes being pointed downward, and the head and neck being arched backward. The muscles are tightened and held rigidly. This type of posturing usually means there has been severe damage to the brain.
A severe injury to the brain is the usual cause of decerebrate posture.
Opisthotonos (a severe muscle spasm of the neck and back) may occur in severe cases of decerebrate posture.
Decerebrate posture can occur on 1 side, on both sides, or in just the arms. It may alternate with another type of abnormal posture called decorticate posture. A person can also have decorticate posture on 1 side of the body and decerebrate posture on the other side.
Causes of decerebrate posture include:
- Bleeding in the brain from any cause
- Brain stem tumor
- Brain problem due to drugs, poisoning, or infection
- Head injury
- Brain problem due to liver failure
- Increased pressure in the brain from any cause
- Primary brain tumor
- Secondary brain tumor
Conditions related to decerebrate posture need to be treated right away in a hospital.
When to Contact a Medical Professional
Abnormal posturing of any kind usually occurs with a reduced level of alertness. Anyone who has an abnormal posture should be examined right away by a health care provider.
What to Expect at Your Office Visit
The person will need emergency treatment right away. This includes breathing assistance and placement of a breathing tube. The person will likely be admitted to the hospital and placed in intensive care.
Once the person is stable, the provider will obtain a complete medical history from family members or friends and do a more complete physical examination. This will include a careful examination of the brain and nervous system.
Family members will be asked questions about the person's medical history, including:
- When did this behavior start?
- Is there a pattern to the episodes?
- Is it always the same type of posture?
- Is there any history of a head injury or other condition?
- What other symptoms came before or with the abnormal posturing?
Tests may include:
- Blood and urine tests to check blood counts, screen for drugs and toxic substances, and measure body chemicals and minerals
- Cerebral angiography (dye and x-ray study of blood vessels in the brain)
- CT or MRI of the head
- EEG (brain wave testing)
- Intracranial pressure (ICP) monitoring
The outlook depends on the cause. There may be brain and nervous system injury and permanent brain damage, which can lead to:
- Inability to communicate
Ball JW, Dains JE, Flynn JA, Solomon BS, Stewart RW. Neurologic system. In: Ball JW, Dains JE, Flynn JA, Doloman BS, Stewart RW, eds. Seidel's Guide to Physical Examination. 8th ed. St. Louis, MO: Elsevier Mosby; 2015:chap 22.
Crocco TJ, Goldstein JN. Stroke. In: Marx JA, Hockberger RS, Walls RM, et al, eds. Rosen's Emergency Medicine: Concepts and Clinical Practice. 8th ed. Philadelphia, PA: Elsevier Mosby; 2013:chap 101.
Heegaard WG, Biros MH. Head injury. In: Marx JA, Hockberger RS, Walls RM, et al, eds. Rosen's Emergency Medicine: Concepts and Clinical Practice. 8th ed. Philadelphia, PA: Elsevier Mosby; 2013:chap 41.
Kellerman RD. Physical and chemical injuries. In: Kellerman RD, ed. Conn's Current Therapy 2015. Philadelphia, PA: Elsevier Saunders; 2012:chap 21.
Mihailoff GA, Haines DE. Motor system I. In: Haines, DE, ed. Fundamental Neuroscience for Basic and Clinical Applications. Philadelphia, PA: Elsevier Saunders; 2013:chap 24.
Woischneck D, Skalej M, Firsching R, Kapapa T. Decerebrate posturing following traumatic brain injury: MRI findings and their diagnostic value. Clin Radiol. 2015;70(3):278-85.