Babinski sign
Học thuậtThân thiện
Definition
Noun: - A specific neurological reflex: The Babinski sign is an abnormal plantar reflex characterized by the upward extension (dorsiflexion) of the big toe and often the fanning of the other toes. It is elicited by firmly stroking the outer sole of the foot from the heel to the ball of the foot.
Usage and Examples
- Clinical Diagnosis:
- The presence of a Babinski sign in the adult patient was a key finding that suggested possible damage to the corticospinal tract.
- A neurologist checks for the Babinski sign as part of a standard neurological examination.
- Developmental Context:
- In infants under two years old, the Babinski sign is a normal reflex due to the immaturity of the nervous system.
Advanced Usage and Notes
- Clinical Significance: In older children and adults, the Babinski sign is not a disease itself but a of an underlying neurological condition. Its presence typically indicates dysfunction of the upper motor neurons, often due to injury or disease affecting the brain or spinal cord (e.g., stroke, multiple sclerosis, spinal cord injury).
- Elicitation: The sign is formally elicited using a blunt instrument to stimulate the lateral plantar surface. The response is considered positive if the great toe extends upward.
Variants and Related Words
- Babinski reflex: A synonymous term for Babinski sign.
- Plantar reflex: The general category of reflex to which the Babinski belongs. A normal plantar reflex in an adult is the downward curling (flexion) of all toes.
- Extensor plantar response: A technical description of the Babinski sign, contrasting with the normal flexor plantar response.
Synonyms
- Babinski reflex
- Extensor plantar response
Antonyms
- Normal plantar reflex (the toes curl downward/flex)
- Flexor plantar response
Noun
- extension upward of the toes when the sole of the foot is stroked firmly on the outer side from the heel to the front; normal in infants under the age of two years but a sign of brain or spinal cord injury in older persons