Polydactyly and polysyndactyly of the foot
Polydactyly of the foot is a congenital malformation in which there are one or more extra toes. When one of these toes is joined to another, it is called polysyndactyly. Treatment depends on the anatomy of the toes and how the bones and joints are arranged. When surgery is indicated, it is usually planned in early childhood, typically between one and two years of age.
- Typical age
- From birth
- Also known as
- Supernumerary toe · Extra toe · Preaxial polydactyly · Postaxial polydactyly · Polysyndactyly
What is it?
Polydactyly is a congenital anomaly in which a child is born with more than five toes on a foot. It is one of the most common congenital malformations of the toes and may occur on its own or with other anomalies. It may affect one or both feet and vary in complexity.
Depending on where the extra toe is, the following types are distinguished:
- Preaxial polydactyly: the extra toe is on the big-toe side.
- Postaxial polydactyly: the extra toe is on the little-toe side; this is the most common form in the foot.
- Central polydactyly: the extra toe is between the middle toes.
In some children the extra toe is well formed, with bones, joints, tendons and a nail. In others it is a smaller or partly developed structure. When two toes are joined, by skin or deeper structures, it is called polysyndactyly.
The cause may be genetic, and sometimes other family members have the same condition. It can also occur on its own, with no family history or other anomalies. Most isolated cases have a good outlook after appropriate treatment.
Signs parents may notice
The most common signs are:
- Six or more toes on one or both feet.
- An extra toe the same size as the others or smaller.
- Two toes partly or completely joined by skin.
- Duplicated nails, toes sharing tissue or abnormal spacing between toes.
- Difficulty finding comfortable shoes when the extra toes make the foot wider.
- Deviation of neighbouring toes or a change in the shape of the forefoot.
The outward appearance does not always reflect how complex the malformation is. Two toes that look separate may share bone or joint structures.
When to see a specialist
An assessment by a paediatric orthopaedic surgeon is recommended when an extra toe is noticed at birth, even if it causes no discomfort.
The assessment is particularly important when:
- The extra toe is large or joined to another toe.
- The big toe, little toe or the rest of the forefoot is deviated.
- The child has difficulty wearing shoes or walking.
- There is a family history of polydactyly or other congenital anomalies are noticed.
When is it urgent?
Isolated polydactyly is not usually an emergency. However, if the toe turns bluish or very pale, feels cold or becomes very painful, seek urgent medical attention to rule out a circulation problem.
How is it diagnosed?
The diagnosis is made by clinical examination of the foot. The specialist assesses the number and shape of the toes, forefoot alignment, movement, the skin and any connections between structures.
An X-ray is the main imaging test for planning treatment. It shows how many bones are present, how the extra toes articulate and whether they share structures with neighbouring toes.
In more complex malformations other imaging tests may be needed to understand the anatomy better. If polydactyly affects both feet, there is a relevant family history or other anomalies are present, a genetic assessment may be indicated.
Treatment
Treatment depends on the shape of the foot, the anatomy of the toes and how the bones and joints are arranged.
Conservative treatment
When the extra toe is small, does not affect foot alignment and causes no functional problems or difficulty with shoes, the specialist may recommend clinical monitoring.
Conservative treatment does not remove the extra toe. Its aim is to monitor growth and check that no deformities, discomfort or footwear problems develop.
Do not try to tie off, cut or remove the toe at home. Even toes that look small may have blood-vessel, nerve or tendon connections that need professional assessment.
Surgical treatment
Surgery is considered when the extra toe causes significant cosmetic concerns, makes wearing shoes difficult, affects foot alignment or could compromise future function. It may also be indicated in certain complex malformations, even if they cause no symptoms in the first months of life.
The operation is tailored to each child’s anatomy. It may involve removing the extra toe and reconstructing the soft tissues, or require additional procedures on the bones, joints, tendons and ligaments to achieve a balanced, functional foot.
In polysyndactyly, separating the toes may require more careful reconstruction of the skin and shared structures. The aim is not just to remove the extra toe, but to achieve good alignment, a well-shaped forefoot and a lasting functional result.
Surgery is usually performed under general anaesthesia. It may be done as a day case or require a short stay, depending on the complexity of the operation and the child.
The timing of surgery is individual, but in many cases it is planned in the second year of life, before growth and regular shoe-wearing make the deformity more obvious. There is no single age that suits every patient.
Outlook and recovery
The outlook is usually good, especially in isolated and less complex forms. Most children can walk normally and wear ordinary shoes after appropriate correction.
After surgery, a special dressing, splint or cast may be needed for several weeks, depending on the type of reconstruction. When weight-bearing and normal shoes can resume depends on the stability of the correction and on bone healing if bone procedures were performed.
As a general guide:
- First weeks: protecting the operated area, controlling swelling and wound care.
- Between 3 and 6 weeks: clinical and X-ray check-up when indicated, and gradual removal of immobilisation depending on progress.
- Return to school: usually within one or a few weeks, depending on pain, mobility and whether the foot needs to be kept raised or immobilised.
- Sport: resumed gradually once the wound has healed and the specialist confirms the foot is ready, often after several weeks and later after bone reconstruction.
Later check-ups monitor healing, toe alignment and foot growth. In some cases a difference in toe size, a visible scar or a residual deviation may remain, so follow-up during growth is important.
This page is for general information and does not replace an assessment by a specialist. If you are worried about your child's foot, talk to their paediatrician or book an appointment.