Pollicization is a reconstructive surgery in which the index finger is migrated to the position of a thumb.

Primarily used for infants and other patients who were born without a thumb or have lost it in injury, Pollicization entails shifting the index finger and rotating it to the thumb’s usual orientation while leaving its arteries and veins attached, connecting it to the tendons that are left over from the previous thumb or substituting those of the index finger to restore the function of the thumb.