Babinski Reflex (Babinski Response) (Babinski Sign)
The Babinski reflex (response or sign) is an important neurologic test based upon what the big toe does when the sole of the foot is stimulated. If the big toe goes up, that may mean full or partial loss of “upper motor neuron” oversight of the nervous system as occurs in various forms of brain injury or disease. The Babinski reflex is obtained by stimulating the lateral surface of the sole. The examiner begins the stimulation at the heel and goes forward to the base of the toes typically by dragging the end of a percussion hammer handle along the lateral part of the sole of the foot. There are diverse ways to elicit Babinski response. A useful way that requires no special equipment is with firm pressure from the examiner’s thumb. Just stroke the sole firmly with the thumb from back to front along the outside edge. Care must be taken not to overdo it. Too vigorous stimulation may cause withdrawal of the foot or toe, which can be mistaken as a Babinski response. The Babinski reflex is characterized by extension of the great toe and also by fanning of the other toes. Most newborn babies are not neurologically mature and therefore show a Babinski response.