This MedLibrary.org supplementary page on Babinski sign is provided directly from the open source Wikipedia as a service to our readers. Please see the note below on authorship of this content, as well as the Wikipedia usage guidelines. To search for other content from our encyclopedia supplement, please use the form below:
Related Sponsors
In medicine and neurology, the Babinski response to the plantar reflex is a reflex, named after Joseph Babinski12 (1857-1932) (a French neurologist of Polish descent), that can identify disease of the spinal cord and brain and also exists as a primitive reflex in infants. When non-pathological it is called the plantar reflex while the term Babinski's sign refers to its pathological form.
Contents |
Methods
The lateral side of the sole of the foot is rubbed with a blunt implement so as not to cause pain, discomfort or injury to the skin; the instrument is run from the heel along a curve to the toes3 (metatarsal pads). There are three responses possible:
- Flexor: the toes curve inward and the foot everts; this is the response seen in healthy adults.
- Indifferent: there is no response.
- Extensor: the hallux dorsiflexes, and the other toes fan out - the Babinski's sign indicating damage to the central nervous system.
As the lesion responsible for the sign expands so does the area from which the afferent Babinski response may be elicited. The Babinski response is also normal while asleep and after a long period of walking.
Interpretation
The Babinski’s sign can indicate upper motorneuron damage to the spinal cord in the thoracic or lumbar region, or brain disease constituting damage to the corticospinal tract. Occasionally, a pathological plantar reflex is the first (and only) indication of a serious disease process, and a clearly abnormal plantar reflex often prompts detailed neurological investigations, including CT scanning of the brain or MRI of the spine, as well as lumbar puncture for the study of cerebrospinal fluid.
In infants
Infants will also show an extensor response. A baby's smaller toes will fan out, and their big toe will dorsiflex slowly. This happens because the corticospinal pathways that run from the brain down the spinal cord are not fully myelinated at this age, so the reflex is not inhibited by the cerebral cortex. The extensor response disappears and gives way to the flexor response around 12-18 months of age.
Relationship to Hoffmann sign
The Hoffmann's sign is sometimes described as the upper limb equivalent of the Babinski's sign4 because both indicate upper motor neuron dysfunction. Mechanistically, they differ significantly; the finger flexor reflex is a simple monosynaptic spinal reflex involving the flexor digitorum profundus that is normally fully inhibited by upper motor neurons. The pathway producing the plantar response is more complicated, and is not monosynaptic. This difference has led somewho? neurologists to reject strongly any analogies between the finger flexor reflex and the plantar response.citation needed
References
- ^ synd/366 at Who Named It
- ^ Comptes rendus de la Société de Biologie, 1896, volume 48, page 207.
- ^ plantar reflex at Dorland's Medical Dictionary
- ^ Harrop JS, Hanna A, Silva MT, Sharan A (2007). "Neurological manifestations of cervical spondylosis: an overview of signs, symptoms, and pathophysiology". Neurosurgery 60 (1 Supp1 1): S14–20. doi:. PMID 17204875.
External links
|
|||||||||||||||||
|
|||||||||||||||||||||||
Wikipedia content modification information:
- This page was last modified on 23 October 2008, at 17:29.
Wikipedia Authorship and Review
Wikipedia content provided here is not reviewed directly by MedLibrary.org. Wikipedia content is authored by an open community of volunteers and is not produced by or in any way affiliated with MedLibrary.org.
Wikipedia Usage Guidelines
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article on "Babinski sign".
The URL for this specific entry is:
All Wikipedia text is available under the terms of the GNU Free Documentation License. (See Copyrights for details). Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc.