Babinski sign
Pronunciation: buh-BIN-skee
An abnormal plantar reflex indicating upper motor neuron dysfunction, characterized by upward movement of the great toe.
Full Definition
The Babinski sign is a pathological reflex elicited by firmly stroking the lateral border of the sole of the foot from heel to toe. In healthy adults, this stimulus normally produces downward flexion of the toes (negative Babinski). An abnormal or positive Babinski sign involves dorsiflexion of the great toe with fanning of the other toes, indicating damage to the corticospinal tract or upper motor neuron pathways. This finding is normal in infants under 2 years but pathological in older children and adults, suggesting conditions such as stroke, spinal cord injury, brain tumors, or other central nervous system lesions.
Usage
Usage note: Capitalize as proper noun; specify 'positive' or 'negative' rather than 'present' or 'absent' for clarity.
In Context
- "Neurological examination revealed a positive Babinski sign bilaterally, suggesting upper motor neuron involvement." — Clinical examination note
- "The absence of Babinski sign helped rule out significant corticospinal tract damage in this patient with peripheral neuropathy." — Neurological consultation