What indicates a positive Babinski response?

A positive Babinski response is characterized by dorsiflexion of the big toe accompanied by fanning of the other toes, typically indicating the presence of an upper motor neuron lesion in the central nervous system. A normal response in adults involves the plantar flexion of the toes when the sole of the foot is stroked, whereas a positive Babinski indicates a pathological reflex that suggests disruption in the corticospinal tract.

In adults, the appearance of dorsiflexion of the big toe is abnormal and signifies that there may be an underlying neurological issue, often related to conditions affecting the central nervous system such as stroke, multiple sclerosis, or other types of brain or spinal cord injuries. This is why the presence of a positive Babinski reflex is considered a valuable clinical sign in neurological examinations, as it can guide healthcare professionals in diagnosing neurological disorders.

The other options do not reflect the typical characteristics associated with a positive Babinski response nor do they indicate any significant pathology. The fanning of the other toes without CNS involvement does not align with the classic presentation of the Babinski sign, which always includes the big toe's movement. Flexion of the knee when the leg is straightened or extension of the big toe with no significance also do not correlate correctly with