Syndactyly

Syndactyly is a congenital condition in which two digits are joined by soft tissue. The connection may involve only part of their length or extend to the fingertips or toes.

Yes. It can occur in the fingers or toes. Assessment and the need for treatment depend on the digits involved, the extent of the connection and its functional impact.

Yes. In some cases, only the skin and soft tissues are joined; in others, the connection may also include bone, cartilage or the nail.

The most common location is the third web space, between the middle and ring fingers.

In most cases it occurs in isolation. In some children, it may be part of a congenital syndrome or occur with other differences of the hand or foot.

Surgery releases the space between the joined digits and aims to create an appropriate web space so that the digits are separated.

After separation, there may not be enough skin to cover all surfaces of the digits. A skin graft may therefore be taken from the elbow, arm or groin.

Simple syndactyly involves skin and soft tissue, while complex syndactyly also includes a bony or cartilaginous connection. It is complete when the connection extends to the tips of the digits and incomplete when only part of their length is joined.

Assessment includes examining both hands, the upper limbs and, when appropriate, the feet and other associated features. X-rays may be requested to identify bony involvement or another skeletal difference.

Surgery is the only way to physically separate the digits, but mild, incomplete syndactyly without functional limitation does not always require an operation. Toe syndactyly, in particular, may not need surgery when it does not cause functional or footwear problems.

Many hand corrections are planned at around one year of age. The exact timing depends on the digits involved, complexity, growth and the risk of progressive deformity, and should be decided by the child’s surgeon.

Surgical correction of syndactyly in children is usually performed under general anaesthesia. The preoperative assessment confirms suitability and allows the anaesthetic plan to be explained to the family.

When three or more adjacent digits are joined, separating every web space during one operation may not be safe because the blood supply to each digit must be protected. Treatment may therefore be carried out in stages.

The hand or foot is protected with a bulky dressing, splint or cast for several weeks, depending on the technique and healing. Families should follow instructions on keeping the dressing protected, pain relief, elevation and follow-up appointments.

Risks include bleeding, infection, delayed healing, partial graft or flap loss, nerve or blood-vessel injury, nail changes, contracture and skin gradually moving into the new web space. Scars usually soften with time, but growth may make further correction necessary in some cases.