Congenital Hand Deformities

What are Congenital Hand Deformities?

Congenital hand deformities, also known as congenital hand differences, are variations in the normal formation of a child’s hands that occur during fetal development. These conditions encompass a broad spectrum of abnormalities, ranging from minor differences such as uneven fingers to more severe cases like the absence of bones.

Hand deformities are often identifiable at birth and can influence the child’s ability to interact with their environment. The variability in the severity and type of deformities necessitates a range of treatments, aimed at improving functionality and quality of life for the affected children.

Types of ​​Congenital Hand Deformities

There are five main types of congenital hand deformities, each with unique characteristics.

• Syndactyly
  This is characterised by the fusion of two or more fingers. It ranges from simple skin webbing to complex cases involving bones, joints, and nerves. It can be unilateral (one hand) or bilateral (both hands). This condition arises when two or more fingers fail to separate correctly during the early stages of fetal hand development.
• Polydactyly
  This involves the presence of extra fingers, which can vary from small skin tags to fully formed digits. These additional fingers can appear on different parts of the hand, including the thumb side or the small finger side. The incidence of polydactyly is one in every 500 births.
• Symbrachydactyly
  This condition is marked by a range of abnormalities like shortened or underdeveloped fingers, or even complete absence of fingers, typically affecting only one hand. Its incidence is estimated to be one in every 32,000 births. The exact cause of this condition is not known.
• Cleft Hand
  A cleft hand presents with missing fingers or parts of fingers in the centre of the hand, forming a V-shaped cleft. It is typically seen as a gap in the palm, with an absence of the middle finger(s). It may involve one or both hands.

• Club Hand
  In club hand, the child’s forearm and hand are affected, resulting in an inward turning of the forearm. This condition may be linked to other abnormalities in the blood, heart, intestines or spine.There are two types of club hand. Radial club hand leads to thumb-side deformities, where a shortened or absent thumb makes the forearm curve like a J-shaped club. Ulnar club hand involves abnormalities on the pinky finger side, where a shortened or absent ulnar bone causes the wrist to bend.

Causes and Risk Factors

The development of congenital hand deformities is influenced by a combination of genetics, the use of harmful substances and certain medications.

• Genetics
  Genetic influences play a role in the formation of the hands and arms. Changes in genes, whether inherited or occurring spontaneously, can lead to various hand deformities. While some genetic factors are hereditary, others may occur without any known family history.
• Use of Harmful Substances
  The maternal use of substances such as tobacco, alcohol, and illicit drugs has been linked to an increased risk of hand deformities.
• Specific Medications
  Certain medications, including those used for chemotherapy or to treat nausea, as well as infections during pregnancy, may be associated with an increased risk.
• Other Risk Factors
  Although less common, some congenital hand deformities are associated with larger syndromes affecting multiple body parts. The specific cause of many hand deformities remains unknown.

Treatment Options

Treatment options for congenital hand deformities are varied and specific to the type of deformity.

Syndactyly Treatment Options

Surgical intervention is the primary treatment for syndactyly, especially when bone or nerve involvement is present. The procedure involves carefully separating the fused fingers and reconstructing the skin, which may require skin grafts from other body parts to minimise scarring. The surgery is ideally performed when the child is between one to two years old to ensure optimal hand development.

Complex cases may necessitate multiple staged surgeries over time to minimise the risk of complications and ensure the best functional outcome.

Polydactyly Treatment Options

Surgical removal of the extra digit is the standard treatment for polydactyly. The complexity of the surgery depends on the development of the extra finger. A small, poorly developed digit may be removed through a relatively simple procedure, sometimes even by clipping or tying off a narrow tissue stalk at birth, allowing it to fall off naturally.

More developed extra digits necessitate a detailed surgical approach, which includes not only the removal of the extra finger but also the reconstruction of the hand to ensure normal function and appearance.

Symbrachydactyly Treatment Options

In milder forms of symbrachydactyly, customised prosthetic devices can be used to compensate for the missing or underdeveloped parts of the hand, improving the ability to perform daily activities. Physical therapy can also help maximise the use of the existing fingers and enhance overall hand functionality.

For more pronounced cases of symbrachydactyly, surgical options might include reconstructive procedures to elongate the underdeveloped fingers or to create new finger-like structures using bones and tissues from other parts of the body. In some cases, especially when fingers are absent, a combination of surgical intervention and prosthetic use is considered to achieve the best functional outcome.

Club Hand Treatment Options

Initial treatment often involves splinting and casting to gently correct the alignment of the wrist and forearm. These methods are particularly effective in mild cases and are usually initiated soon after birth to take advantage of the flexibility of the baby’s bones and joints.

In more severe cases of club hand, surgery is required. Procedures may include bone lengthening, tendon transfers, and reconstructive surgeries to correct the forearm’s curvature and improve hand position.

Cleft Hand Treatment Options

Mild cases of cleft hands, especially those without functional impairment, may be managed with physical therapy to improve hand strength and dexterity. Splinting and casting can also be used to support proper hand alignment.

Surgery is also used, particularly in cases where the cleft affects hand function or appearance. Surgical procedures aim to close the cleft, realign the fingers, and, in some cases, reconstruct the missing parts of the hand using grafts from other areas of the body. The complexity of the surgery depends on the extent of the deformity, and multiple surgeries over time may be required.