Babinski sign plantar reflex

Babinski Sign (Plantar Reflex) — also called the Extensor Plantar Response — is an important neurological sign used to assess the integrity of the corticospinal (pyramidal) tract.

🔹 Normal (Negative Babinski) Response

Stimulation: Stroking the lateral aspect of the sole of the foot from the heel to the ball, curving medially across the ball.

Response: Plantar flexion (downward movement) of all toes.

Indicates: Normal corticospinal tract function.

🔹 Abnormal (Positive Babinski Sign)

Response: Dorsiflexion (extension) of the big toe and fanning of the other toes.

Indicates: Upper Motor Neuron (UMN) lesion involving the corticospinal tract.

🔹 Physiological in Infants

Normally present up to 12–18 months of age, due to incomplete myelination of corticospinal pathways.

🔹 Causes of Positive Babinski Sign

Seen in Upper Motor Neuron lesions, such as:

Stroke

Multiple sclerosis

Spinal cord injury

Brain tumor

Amyotrophic lateral sclerosis (ALS)

Meningitis or encephalitis (in some cases)

🔹 Mnemonic for Positive Babinski

👉 “Babies Babinski” — babies normally show it, adults shouldn’t.
If present in adults → Bad sign (indicates UMN lesion).

🔹 Other Related Reflexes

Sometimes called pathological reflexes, also indicating pyramidal tract involvement:

Oppenheim’s sign: Stroking down the shin → extension of great toe.

Chaddock’s sign: Stroking around the lateral malleolus → extension of great toe.

Gordon’s sign: Squeezing calf muscles → extension of great toe.

Schaefer’s sign: Squeezing Achilles tendon → extension of great toe.

🔹 Summary Table
Feature Normal (Negative Babinski) Abnormal (Positive Babinski)
Great toe movement Downward (plantar flexion) Upward (dorsiflexion)
Other toes No movement / flexion Fanning out
Indicates Normal corticospinal tract UMN lesion
Normal in infants? No Yes (till ~18 months)