Don’t panic if you have polydactyly or syndactyly. Find out first and then seek medical attention immediately.

When the baby is born, parents find that the baby has an extra finger or some fingers are fused together and cannot be separated. Seeing this situation, they are very panicked and don’t know what to do? The whole family is in an unhappy atmosphere, which brings a lot of trouble to the parents. In fact, polydactyly and syndactyly are common congenital malformations in children. There is no need to panic. You should seek help from a specialist as soon as possible and learn about the relevant knowledge of this disease.

PART 1: What is polydactyly and syndactyly?

Polydactyly, also known as duplicated fingers, refers to the growth of fingers other than normal fingers, phalanges, simple soft tissue components or metacarpal bones. It is the most common congenital malformation of the hand clinically. It occurs more frequently in males than in females and more frequently in the right hand than in the left hand.

The appearance and structure of polydactyly vary. Some are more fully developed, resembling normal fingers, with bones and joints, tendons, nerves, blood vessels and nails, and their movements are often similar to those of the main fingers. Some are just a small piece of flesh connected to the finger by a pedicle. Polydactyly is a common deformity, often coexisting with deformities such as brachydactyly and syndactyly, and is more common in the thumb and little finger.

What is syndactyly?

Syndactyly refers to the joining together and growth of two adjacent fingers. It is the second most common congenital malformation of the hand after polydactyly.

How to prevent polydactyly and syndactyly?

Strengthen pregnancy care and nutrition, avoid respiratory tract infections, gastrointestinal infections, viral infections such as rubella, measles, chickenpox, mumps, etc., and avoid exposure to radiation, drugs and other possible embryo teratogenic factors.

If you find your child has polydactyly or syndactyly, don't panic. You can go to a specialist hospital to seek help from a doctor. Make a clear diagnosis early, follow the advice of the specialist, choose the right time for surgery, and make good preparations before surgery. Have regular follow-up after surgery and strengthen finger function exercises.

PART 2: Causes and types of polydactyly and syndactyly

What causes polydactyly?

The cause is unknown, but some cases are genetic and can be inherited from one generation to the next. Environmental factors can affect embryonic development, such as certain drugs, viral infections, trauma, stimulation from radioactive substances, and especially modern industrial pollution, which can all become teratogenic factors. Damage to the early differentiation of the limb bud blastema is an important cause of polydactyly.

Polydactyly of the thumb is caused by abnormal development of the ectodermal apical ridge, proximal extension of the apex of the thumb side and slow retraction.

What are the types of polydactyly and syndactyly?

Clinically, neoplasia can be divided into three categories according to the different tissue components it contains:

① Soft tissue polydactyly: Polydactyly only has soft tissue growths, without bones, tendons and other tissues;

② Simple polydactyly: Polydactyly contains phalanges, tendons and vascular nerve bundles connected to normal fingers, which is a functional defective finger;

③ Compound polydactyly: Polydactyly is a true duplication that not only contains phalangeal tendons, etc., but also includes metacarpal twins.

Syndactyly can be of several different types:

If two fingers are completely joined together, it is called complete syndactyly.

If two fingers are partially joined together, it is called partial syndactyly.

If the syndactyly consists only of soft tissues such as skin, it is called simple syndactyly.

If part or all of the phalanges of two fingers are fused together, it is called compound syndactyly.

How do syndactyly come about?

During the development of the hand, the fingers begin to be together, and then gradually separate to form a thumb and four fingers. If an abnormality occurs during this process, resulting in incomplete or no separation of the fingers, partial or complete syndactyly will occur. The exact cause of syndactyly is still unclear, a few are hereditary, and most are caused by unknown reasons.