Syndactyly Type 3: Causes, Symptoms, and Treatment
Medically reviewed by Harsha Moole, MD, Internal Medicine. Last reviewed: October 2, 2026.
What kind of doctor treats Syndactyly Type 3?
A primary care doctor is usually the first to see the problem and will refer the patient to a hand surgeon or a plastic surgeon. A geneticist may also be involved when families want testing. A direct primary care or concierge doctor can be a first stop for an evaluation and can refer you to a specialist when needed.
What it is
Syndactyly type 3 is a rare condition where two fingers are joined together, usually the fourth and fifth fingers of both hands. The word syndactyly means fingers that did not fully separate before birth. The ring finger and the little finger share skin and sometimes bone.
Symptoms
The main sign is webbing between the ring finger and the little finger on both hands. The joined fingers may be shorter than usual, and the little finger can bend toward the other fingers. Most people have no other health problems.
Causes and who gets it
Syndactyly type 3 is caused by a change in a gene called GJA1. It is passed down in an autosomal dominant pattern, meaning a child needs only one copy of the changed gene, from one parent, to have the condition. It affects both boys and girls and has been reported in families around the world.
How doctors diagnose it
A doctor can often spot the condition by looking at the hands. An x-ray shows whether the joined fingers share bone or only skin. Genetic testing can confirm the diagnosis in some cases.
Treatment
Treatment is surgery to separate the joined fingers, usually done when the child is young so the fingers can grow and work separately. The surgeon cuts the web of skin and covers the raw edges, often with skin taken from another part of the body. Many people gain good use of the hand, but the outcome depends on how the fingers were joined.
When to see a doctor
Talk to a doctor soon after birth if a baby has joined fingers, or if you notice webbing between your own fingers. Early evaluation helps families plan for treatment. Other reasons include pain, a curving finger, or poor healing after surgery.
How a direct primary care or concierge doctor fits in
A direct primary care doctor charges a flat monthly fee instead of billing insurance and can evaluate joined fingers, order x-rays, and coordinate care. A concierge doctor works in a similar way but usually charges more and often works alongside insurance. The surgery itself is done by a specialist; after surgery, these doctors can handle follow-up visits and watch how the hand heals.
Common questions
Does syndactyly type 3 hurt?
No, the joined fingers themselves usually do not cause pain. Problems can come later if the fingers curve or if surgery has complications. Most people live with the condition comfortably if they choose not to have surgery.
Can it be fixed without surgery?
No, surgery is the only way to separate fingers that are joined. Stretching or splinting does not work for this condition. Some people with mild webbing choose not to have surgery at all.
Will my children have it too?
If a parent has the changed GJA1 gene, each child has a one in two chance of getting it. A genetic counselor can help families understand the chances. Not every child who inherits the gene will have joined fingers.
How soon is surgery done?
Surgeons often separate the fingers when a child is between one and two years old, but timing varies. The surgeon considers how the fingers are joined and how the hand is growing. Each case is planned individually.
Sources
Medical Disclaimer
This content is for general educational and informational purposes only and is not medical advice. It is not a substitute for professional medical advice, diagnosis, or treatment, and reading it does not create a doctor-patient relationship. Always seek the advice of your physician or another qualified health provider with any questions about a medical condition, and never disregard or delay seeking professional advice because of something you read here. If you think you may have a medical emergency, call 911 (or your local emergency number) immediately.
