Definition
Abnormal posturing is different from what is commonly called "bad posture" or "slouching." Instead, it is a tendency to hold a particular body position, or to move one or more parts of the body in a particular way. This phenomenon is an important part of evaluating a person in a coma. Certain abnormal posturing behaviors may be a sign of specific injuries to the central nervous system.
Alternative names
Pathologic posturing; Evaluating a person in a coma
Causes
Cerebral edema Increased intracranial pressure due to any cause Reye syndrome Severe head injury Stroke Uncal herniation
Definition
Abnormal posturing is different from what is commonly called "bad posture" or "slouching." Instead, it is a tendency to hold a particular body position, or to move one or more parts of the body in a particular way.
This phenomenon is an important part of evaluating a person in a coma.
Certain abnormal posturing behaviors may be a sign of specific injuries to the central nervous system.
Alternative names
Pathologic posturing; Evaluating a person in a coma
Considerations
Abnormal posturing present with little or only mild stimulation is a sign of serious central nervous system damage. Subtle abnormalities or damage of the nervous system may be brought out as posturing when performing certain tasks, such as walking on the sides of the feet, on the toes, or heels.
Normally, when a muscle contracts, the muscles on the opposite side of the joint provide some resistance to contraction. Abnormal posturing occurs when damage to the central nervous system (brain or spinal cord) results in complete or partial lack of opposition to muscle contraction in various muscle groups.
See the following types of abnormal postures:
- Decerebrate posture -- rigid extension of the arms and legs, downward pointing of the toes, and backward arching of the head
- Decorticate posture -- rigidity, flexion of the arms, clenched fists, and extended legs
- Opisthotonos -- rigidity and severe arching of the back, with the head thrown backwards
An affected person may alternate between different postures as the condition fluctuates.
Injury or inflammation of a portion of the brain, spinal cord, or nervous system is the most common cause of abnormal posturing. The particular type of posturing can reflect the type and area of nervous system involvement.
When to contact a medical professional
Abnormal posturing often accompanies reduced consciousness. Anyone who shows such behaviors 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.
What to Expect at Your Office Visit
All conditions of spontaneously or easily triggered abnormal posturing require hospital treatment. This kind of movement is most normally seen in patients in coma. More subtle posturing that is triggered by a doctor at a medical visit may or may not be important.
At the hospital, emergency measures for abnormal posturing must be started immediately. This includes placement of an artificial airway (breathing tube) and assistance with breathing. The person will likely be hospitalized in intensive care.
The medical history will be obtained from family members and a physical examination will be performed.
Medical history questions documenting abnormal posturing in detail may include:
- When did this behavior start?
- Is there a pattern to the occurrences?
- Is it always the same type of posture?
- What other symptoms preceded or accompanied the abnormal posturing?
- Is there any significant medical history (such as a known head injury)?
The physical examination will include a complete neurological assessment.
Diagnostic testing may include:
References
Bleck T. Levels of consciousness and attention. In: Goetz, CG, ed. Textbook of Clinical Neurology. 3rd ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 1.
A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org). URAC's accreditation program is an independent audit to verify that A.D.A.M. follows rigorous standards of quality and accountability. A.D.A.M. is among the first to achieve this important distinction for online health information and services. Learn more about A.D.A.M.'s editorial policy, editorial process and privacy policy. A.D.A.M. is also a founding member of Hi-Ethics and subscribes to the principles of the Health on the Net Foundation (www.hon.ch). The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997- 2008 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.
Review Date: .3/26/2009
Reviewed By: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; and Daniel B. Hoch, PhD, MD, Assistant Professor of Neurology, Harvard Medical School, Department of Neurology, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.3/26/2009
