Your child has been diagnosed with thumb duplication (preaxial polydactyly) and recommended surgery. The information on this page describes the surgical options for removing an extra thumb, the risks of the procedure, and how to take care of your child at home after the surgery.
Treatment options
Surgery may be the recommended treatment for a duplicated thumb, depending on the structure and function of your child’s thumb. Families can choose not to have surgery to remove the extra thumb, if the extra thumb is not causing a problem with function.
Surgery may not be recommended if removing the extra thumb would be harmful to your child or worsen their hand function. However, it is rare that removal of an extra thumb causes functional problems.
Surgical removal in the plastic surgery clinic (rare)
Your child may undergo removal in the plastic surgery clinic if their extra thumb is connected by a loose skin stalk and they are either under three months or above 10 years of age. The procedure will be performed under local anesthetic in clinic, meaning your child will be awake for the procedure. Your child’s finger will be numb from the anesthetic. You will be with your child the entire time unless your preference is to be outside of the room.
If your child is under three months of age, bottle or breastfeeding during the procedure is encouraged to allow the optimal experience for your baby. You should time your baby’s feeds so that they are due to feed when the procedure starts.
The procedure will take approximately 30-45 minutes to remove one extra digit, and 60 minutes to remove two extra digits. Dissolving stitches will be used to close the skin and surgical glue will help to protect the incision as it is healing.
Note: If your child is between three months of age and 10 years of age, they must have their procedure done in the operating room (see information below).
Surgery in the operating room (most common)
If your child’s extra thumb is connected by a bony stalk, they will undergo removal in the operating room. Duplicated thumb surgery involves the surgeon making an incision around the extra thumb to remove it. The surgeon may also need to reconstruct the ligament in the thumb that is not removed, to allow it to be as strong as possible.
Surgery is completed using general anaesthesia; therefore, your child will be asleep. Localized freezing (local anaesthesia) will be given during the surgery, which will numb the thumb for a few hours. The total surgical time is approximately one to three hours, and your child may go home from the recovery room afterwards.
Surgery to remove the duplicated thumb will not make the remaining thumb on that hand normal; the remaining thumb will still be smaller in size, may remain underdeveloped and may function less well had there been a single thumb. This is a result of how the thumb originally developed before birth. However, the thumb will continue to grow as your child grows.
Timeframe for treatment
Children generally undergo duplicated thumb surgery in the operating room around one to two years of age. However, this surgery is elective, and there is no urgency to remove the extra thumb. Children with some types of duplicated thumbs may require secondary surgery to optimize function and appearance. If secondary surgery is recommended, this is usually done after five years of age.
After the procedure
If surgery is completed in the plastic surgery clinic, your child may go home after their procedure is completed.
If surgery is completed in the operating room, your child will go to the recovery room for about one to two hours. Once your child is eating and drinking well and their pain is under control, they may go home.
Risks and complications of surgery
- As with all surgeries, there is a risk of infection. This risk is low and would be treated with antibiotics.
- There is a small risk of nerve injury, which can cause numbness to the thumb. This usually resolves over time.
- Your child will have a scar down the side of the thumb and/or hand; however, the scar generally heals well.
- There is a risk that the thumb may not be completely straight. Additional surgeries may be recommended to correct a severely crooked thumb.
Caring for your child after the procedure
Skin care
For surgery on loose skin stalk connections, the thumb will be covered with surgical glue and may also have a bandage. Your child may resume regular bathing with soap and water after the procedure if they do not have a bandage. Please avoid applying lotion or cream to the site, as these can cause the surgical glue to break down. If your child has a bandage, it is important to keep the bandage clean and dry. To bathe your child, sponge baths work well.
The surgical glue will flake off gradually within the first one to two weeks after the procedure. Usually, the stitches will be fully dissolved, and the incision will be fully healed two to three weeks after the procedure.
Cast
For surgery on bony connections, your child’s hand and arm will be placed in a cast for approximately two to four weeks after surgery. Depending on your child’s age, the cast may also include the elbow and upper arm. It is important to keep the cast clean and dry. To bathe your child, sponge baths work well.
Swelling
To prevent swelling, elevate your child’s arm above the level of their head using an extra pillow to keep the hand propped up.
Pain
To control pain after surgery, you may give your child acetaminophen and ibuprofen as needed.
Activity
Restrict strenuous activity for the first few weeks after surgery.
Follow-up
After surgery done on a bony connection, your child will be seen in the plastic surgery clinic to remove their cast and evaluate their healing.
Children tend to do very well following surgery. They are typically back to using their hand fully by six weeks after the operation.
It is uncommon to require physiotherapy after this operation, but an occupational therapist may be involved in your child’s care to help with scar management. Scar massage is used to improve the appearance of surgical scars. See Scar massage for surgical scars for more information.
You child can expect to return to the plastic surgery clinic once every few years to check their thumb as they grow and to assess their hand function.