Polydactyly
| Polydactyly | |
|---|---|
| Other names | Hyperdactyly; polydactylism; supernumerary digits |
| A left hand with postaxial extra finger | |
| Specialty | Medical genetics |
| Symptoms | Extra fingers or toes |
| Complications | Pain, low self-esteem, clumsiness |
| Usual onset | Early development |
| Types | Syndromic Non-syndromic: Pre-axial, axial or central, postaxial |
| Treatment | Surgery |
| Frequency | 4 to 12 per 10,000 |
Polydactyly is a birth defect that results in extra fingers or toes. The hands are more commonly involved than the feet. Extra fingers may be painful, affect self-esteem, or result in clumsiness.
It is associated with at least 39 genetic mutations. It may either present alone or with other defects. Cases may run in families. The underlying mechanism involves an error in limb bud formation during early development. Diagnosis may occur before birth via prenatal ultrasound as early as nine weeks. X-rays may be useful after a child is a year old. The opposite is oligodactyly (fewer fingers or toes).
Treatment varies from removal by cautery to more involved surgery. While putting a tight band around the base has been carried out, this is not typically recommended. If surgery is required, this is often done around two years of age. Occasionally multiple surgeries are required.
Polydactyly is present in about 4 to 12 per 10,000 newborns. It is the most common defect of the hands and feet. In the United States, Black people are more commonly affected than white people. The term is from Greek πολύς (polys) 'many' and δάκτυλος (daktylos) 'finger'.