Thumb Polydactyly

What Is Thumb Polydactyly?

Thumb polydactyly is a condition in which more than one thumb is present on a hand. There are many appearances and varieties of thumb duplications, varying from a broad fingernail to a complete double thumb. Polydactyly can involve bone, joint, muscle, tendon, nerve, blood vessels and/or skin. Usually it occurs on one hand only, and neither thumb is completely formed.

What Causes Thumb Polydactyly?

Thumb polydactyly can occur in many forms, most commonly because the child's thumb formed into two parts during the second month of pregnancy.

How Is Thumb Polydactyly Treated?

Treatment options vary based on the anatomy of each thumb but generally involve reconstructive surgery of the bone, ligaments and tendons. Sometimes, parts of the two thumbs may be combined to build the best possible thumb for the child.

The best time for treatment is when the child is old enough to safely undergo an elective procedure and when the thumb is large enough for the doctor to perform a more technical procedure with precision. A protective cast will be worn after the surgery until the thumb is healed.