When a child is born without a thumb, the process of pollicization may allow surgeons to re-place the index finger so that the body can use that digit as a thumb. The procedure most often occurs when the child is between 1 and 2 years old, and naturally developing the ability to manipulate the hand.
The procedure requires the surgeon to shorten one of the bones that make up the index finger. This creates a digit that is similar in length to a natural thumb. The surgeon then shifts the index finger, without amputation, into position.
Most children are able to leave the hospital the day after surgery, though the repositioned thumb will not begin to function until the surgical site has begun to heal. This typically happens after approximately four weeks. Over the course of the next few months, an occupational therapist helps the child to use the thumb, which typically develops full range of motion by the 12th week after surgery.