Thumb duplication

Thumb duplication


What is thumb duplication?

Thumb duplication refers to a congenital condition in which your child has two thumbs on one hand. These thumbs tend to be smaller and relatively underdeveloped.

What causes thumb duplication?

No one knows the exact cause. Most cases occur by chance while a baby is developing in the womb. There’s no defined genetic link. In some instances, there may be some family connection, particularly if your child has a thumb with three bones instead of two.

How common is thumb duplication?

It’s estimated that it in 1 out of every 1,000 births, more commonly in boys than girls.

How is pre-axial polydactyly diagnosed?

Through a thorough medical history and careful physical examination. X-rays are used to confirm the diagnosis and to identify which bones are affected.

How is pre-axial polydactyly treated?

Your child will need surgery to create a single, functioning thumb. Typically, this surgery performed when your child is around 1 year old. As each thumb is relatively underdeveloped, surgery often involves sharing key elements from each to recreate one fully functional thumb.

What happens after surgery?

After surgery, your child’s hand is usually placed in a bulky padded bandage for two weeks to help immobilize and protect it. We will organize for your child to see a specialist physiotherapist to improve their thumb and hand. After treatment your child should have a fully functional thumb. It may be a bit smaller than the other thumb, but should have almost normal function. Long-term follow-up may be required to ensure good function as your child grows.