What Is Decorticate Posturing?
A physical reflex response to extensive brain damage
Medically reviewed by Nicholas R. Metrus, MD
Decorticate posturing is a physical position that occurs as a reflex in response to substantial brain damage. With decorticate posture, a person extends their legs, flexes their arms, clenches their fists, and has rigid muscles, without any interaction or responsiveness. This is an involuntary movement, which means that it is not on purpose.
Decorticate posturing indicates an injury to both sides of the brain, which could occur due to a stroke, traumatic brain injury, or any other cause of severe brain swelling. In some situations, another medical condition, such as seizure, could appear similar to decorticate posturing. An accurate diagnosis and prompt treatment are important.
This article describes decorticate posturing, its causes, treatments, and outcomes.
Illustration by Michela Buttignol for Verywell Health
Decorticate Posturing and the Brain
Decorticate posturing occurs due to a substantial disruption of brain function on both sides of the brain. Normally, the neurons (nerve cells) in the brain are stimulated in a systematized pathway, as some neurons activate your physical movements, while other neurons inhibit these movements—for an overall well-balanced result.
When neurons are damaged, reflexes may take over due to an imbalance of activation and inhibition. This is what is happening with decorticate posturing.
Causes of decorticate posturing include:
Brain tumor, causing swelling and pressure in the brain
Infection or inflammation of the brain tissue on both sides of the brain
Encephalopathy (damage to brain tissue), which can be caused by severe disease of the liver, kidneys, or systemic (whole-body) infection
Effects
The changes in the brain that lead to decorticate posturing cause physical effects on the body.
Decorticate posturing looks like:
Legs extended
Arms flexed at the elbow towards the body
Wrists flexed
Fists clenched
Shoulders pulled toward the body
This occurs in a very serious acute medical situation and the person would not be looking around, walking, talking, or reaching when the posturing occurs.
Is It Permanent?
When diagnosed, decorticate posturing can be a sign of permanent brain damage. However, some treatable situations can cause an appearance similar to decorticate posturing.
In rare instances, treatable medical conditions may cause decorticate posturing. In these situations, treatment of the underlying condition can prevent permanent brain damage.
Decorticate vs. Decerebrate Posture
Decorticate posture and decerebrate posture are both reflex physical positions that occur due to extensive brain damage on both sides of the brain. Both of these are signs of severe, life-threatening brain injuries with a very low chance of survival.
Decorticate posture involves extension of the legs and flexion of the arms, while decerebrate posture involves extension of the legs, arms, trunk, and neck.
Decorticate posture is generally associated with severe damage to both sides of the cerebral cortex. While decerebrate posture is similarly associated with damage to the cerebral cortex, it is also associated with damage to the midbrain portion of the brainstem.
Immediate and Life-Saving Treatment
Decorticate posturing is a sign of substantial brain damage. When there is a risk of this condition (such as when someone has had a major stroke), your healthcare providers will initiate therapy to try to prevent decorticate posturing from developing. In some cases, treatment of the underlying condition can be started even after decorticate posturing develops.
Treatment and Prevention
Preventative treatment includes medication to reduce swelling and excess fluid in the brain. These treatments include steroid medication or diuretics (water pills).
In some instances, such as when extensive swelling is anticipated, a shunt (tube) can be placed between the skull and the brain tissue to absorb excess fluid before pressure builds up in and around the brain.
Preventative approaches may involve brain surgery to remove excessive blood or removal of a brain tumor that could cause excessive pressure on the brain.
Treatment for decorticate posturing that has already developed is similar to preventative therapies. However, in many instances, decorticate posturing indicates a very low chance of survival. Such treatments might be harmful or would not be beneficial at a late stage after this posturing develops.
Limitations of Prevention and Treatment
Decorticate posturing is not always related to a treatable condition, and sometimes, it is not possible to prevent the condition. Additionally, sometimes decorticate posturing can develop suddenly without any opportunity to prevent it.
Decorticate Posturing Lesions on Scans
The diagnosis of decorticate posturing is based on observation of the physical movements, as well as consideration of the risk factors and medical history. Sometimes, diagnostic studies are done to help visualize and define the brain damage.
Brain imaging tests can identify changes in the brain that could cause decorticate posturing. A brain magnetic resonance imaging (MRI) test or brain computerized tomography (CT) can be used to visualize the type and extent of damage in the brain. In some cases, if the type of brain damage is treatable, therapy would be initiated with medication or surgery.
An electroencephalogram (EEG) is a brain wave test that may be used to assess brain activity. This test can often differentiate between severe brain damage and a seizure.
Risks and Complications
Decorticate posturing is not harmful, but it is a sign that someone has experienced severe harm to the brain. This brain damage, or its cause, could produce further damage to other organs in the body, such as the heart, lungs, liver, kidneys, and digestive system.
Prognosis With Decorticate Posturing
Decorticate posturing is associated with a very bad prognosis. The likelihood of survival is considered low when someone has developed decorticate posturing.
However, it’s important to rule out other possibilities, such as seizures, a psychiatric reaction, medication side effects, infection, or organ damage that could be reversible.
Support and Ongoing Care
Decorticate posturing is not usually reversible and is generally associated with a very low chance of survival. If you have a loved one with this physical sign, it’s crucial that you discuss your loved one's prognosis with their healthcare team. You might need to meet with a neurologist, palliative care specialist, or another specialized physician about end-of-life care plans.
In rare circumstances, certain treatable medical conditions can cause signs that appear similar to decorticate posture. The medical history, risk factors, and diagnostic testing can differentiate such conditions.
For example, seizures may cause extension and flexion of the extremities in a pattern that looks like decorticate posture. Seizures can be treated, and they are not usually life-threatening.
Related: End-of-Life-Care: What Loved Ones Should Know
Summary
Decorticate posture is a physical reflex that occurs in response to severe brain damage on both sides of the brain. This physical sign is associated with a very low chance of survival.
Other conditions may sometimes cause an appearance similar to decorticate posture—medications, seizures, and psychiatric reactions. In such situations, the medical history and diagnostic testing will differ significantly from that of decorticate posture, and treatment can be initiated.
When there is a high risk of decorticate posture, such as after head trauma, the medical team may use therapies to prevent this extensive brain damage from occurring. If you have a loved one who is displaying decorticate posture, you will need to discuss the prognosis with the medical team so that you can make decisions regarding life support.
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