What are congenital hand deformities?
Congenital differences in hands affect both the shape and function of the baby’s hand and arm. They occur in 20 out of 10,000 babies born and are more common in boys than girls. Congenital hand deformities can be prevented especially as the child learns to interact with the environment through the use of her hands. The degree of deformity ranges from a minor deformity, such as uneven or irregular fingers or toe deformity, to a severe deformity, such as complete lack of bone.
Early consultation with a hand surgeon is an important part of the treatment process for children born with congenital hand deformities. Although reconstructive surgery is not possible, a wide variety of prosthetic devices can be used to increase performance.
Congenital hand deformities are generally not detected before birth. Occasionally a prenatal ultrasound can see a difference such as extra fingers or missing bones, but this is very rare. Congenital hand deformities are often divided into two categories:
- Malformations: In which the hand or part of the arm does not develop normally while the baby is in the womb, and
- Deformations: In which the hand and arm usually begin to develop, but are somehow prevented from doing so.
Defects occur when the baby’s upper extremities first develop 4 to 8 weeks after conception. Disabilities occur after pregnancy.
Types of congenital hand deformities
Pediatric orthopaedic and plastic surgeons diagnose and treat children with all types of hand defects. There are many types. The following are the most common congenital hand deformities.
Extra digits (polydactyly)
Polydactyly is the most common congenital hand deformities. It affects boys and girls equally. A baby born polydactyly has more than five thousand on one side. The extra finger is usually a small piece of soft tissue that can be removed. Sometimes the extra toe contains the bones but not the joints. Very rarely, a series of extra fingers will do. A baby can be born with many extra fingers. There are several types of polydactyly:
- Preaxial polydactyly: Contains an extra finger. It is more common in Caucasians. The pediatric surgeon can repair tendons by removing excess bone and skin.
- Postaxial Polydactyly: Has extra fingers on the opposite side (“little finger” side). It is more common in African Americans. These can occur as complete and distinct fingers or small stumps. Stumps can be treated by a hand specialist in the office.
- Central polydactyly: Additional fingers are found between the fingers, but this is less common.
Fused fingers (Syndactyly)
Fused fingers (syndactyly) Example Syndactyly is one of the most common birth defects of the upper extremities, occurring in up to 1 in 2000 live births. This condition occurs when the baby is unable to separate two or more fingers during pregnancy, resulting in “webbed” fingers at birth. It usually consists of the middle and ring fingers.
Syndactyly affects boys twice as much as girls. Family history is frequent and, in these cases, it is usually fingers and toes. Children may need surgery before 18 months to separate the fingers or toes, and additional skin may need to be removed from a specific area of the body, depending on the degree to which the fingers have joined. Situation categories:
- Finish syntactically: Skin meets affected fingers or toes.
- Incomplete: Only the fingers or toes are on the way to the tips.
- Simple syndactyly: The fingers or toes are attached only through the skin and soft tissues.
- Complex syndactyly: The bones of the fingers intertwine with each other.
Undeveloped hand (Symbrachydactyly)
Babies born with symbrachydactyly have small or missing fingers. They may also have webbed fingers or a small hand or forearm.
- Mild symbrachydactyly: Mobile fingers slightly smaller than the hand, with small membranes. There are bones in the hand and some bones in the fingers and toes. Moderate symbrachydactyly: Most or all of the finger bones are absent and the baby has small projections of skin and soft tissue. The toe is normal, but it may be smaller.
- Symbrachydactyly acute: The baby does not have a toe or toes and partial fingers.
- Club hand: Example Babies with club hands lose part or all of the two long bones that make up the forearm: the radius or the ulna. As a result, the forearm may be lower than normal. The hand is turned inward, limiting the movement of the wrist. A child with this condition may have a hard time doing the things that her hands require. This condition is most often seen on one side of the hand or the other side: the radial side (toe) or the ulnar side (little finger).
- Radial club hand: Children with a club hand on the radial side (radial dysplasia) often have the forearm and wrist bent at the ball of the foot. After a child is 6 and 12 months old, surgery may be recommended to straighten the forearm and repair tendons. The condition may be related to other medical syndromes such as Fanconi anemia, Holt-Oram syndrome, and Water syndrome.
- Ulnar equinovarus arm: This condition is less common than the radial equinus varus arm and is not usually associated with other syndromes. It varies from mild to more severe cases with the baby’s wrist and is fixed and bent towards the side of the short finger of the hand. Deformity or absence of the toe.
Cleft arm (ectrodactyly)
Split hand: Sample hand (also known as ectrodactyly or split hand) when the central part of the sample develops abnormally. Children with this condition do not have one or more middle fingers on their hands.
There are generally two types:
- Typical cleft hand: V-shaped and the middle fingers are usually missing or partially missing. Usually, both arms are affected and sometimes the feet as well. The family history of this type of arm cleft is frequent.
- Divergent wedge arm: It is U-shaped and usually has only one arm. This type of cleft hand is often not inherited. A heterogeneous cleft arm can be a symptom of Poland syndrome.
Small thumbs (hypoplastic)
Little (Hypoplastic) Toe: Example Hypoplastic toe is not fully formed during pregnancy or is completely absent at birth. Treatment depends on how secure or stable the joint that connects the base of the toe to the wrist is. Children with stable joints use their thumbs in regular play. Children with unstable joints tend to ignore the big toe. For stable wrist and toe joints, reconstructive surgery is generally recommended to strengthen the toe and its tendons. For loose or floating unstable joints, the little finger is removed and the index finger is replaced with the big toe.
Stimulate the toe
Sometimes babies are born with an abnormality in the toe tendon, making it difficult to flex. This condition disappears on its own by one year of age. At other times, surgical correction may be recommended before age 3 to release the tendon and allow the toe to function properly.
What causes congenital hand deformities?
Between the fourth and sixth week of pregnancy, the fetus develops arms and hands. Any interruption of this process can cause congenital hand deformities. Many factors affect the development of the human hand. These factors are generally divided into genetic and environmental factors. Genetic factors include changes in the information of the genes that cause the formation of hands and arms. Genes are the basic biological unit of heredity and are passed on to children by their parents. They contain instructions for the growth and function of every cell in the body. In the case of differences in hands, genetic changes usually occur for no apparent reason (abrupt). The changes that occur in families are minimal.
Environmental factors include infections and thalidomide (a drug used to treat nausea) and some drugs used for chemotherapy. These factors cause the deterioration of healthy tissue, alter the development process and cause a difference in the structure of the hand. Some congenital hand deformities can be explained by these factors, while others have no unknown cause. In some cases, the difference of hands is an isolated event. In other cases, the difference is part of a syndrome that affects multiple parts of the body.
What are the benefits of treatment for congenital hand deformities?
Each child with a hand difference is unique and the approach to treatment depends on the individual needs of the child. The main goal and purpose of treatment are to improve the child’s ability to work differently. Another goal is to improve the shape of the hand and support the child’s self-esteem. Options for dealing with congenital hand deformities:
- Splinting or cast
- Physical therapy (to help increase strength and performance)
- Prosthesis (in case parts or bones are missing)
Specific treatment for congenital hand deformities is determined by your paediatrician based on:
- Your child’s age, general health, and medical history
- The extent of the situation
- The cause of the condition
Your child’s tolerance for specific medications, procedures, or treatments.
- Estimates of the course of the situation
- Your opinion or preference
- Treatment may include:
- Limb manipulation and stretching
- Rupture of affected organs
- Tendon transfers
- External tools (to help identify deformed fingers or hands)
- Physical therapy (to help increase arm strength and function)
- Correction of contracts
- Skin grafts: These include replacing or attaching the skin to a part of the hand that was missing or removed during a procedure.
- Prosthesis: These can be used when surgery is not an option or in conjunction with surgical correction.
Surgery for congenital hand deformities
The treatment perspective varies depending on the type and complexity of the difference. When congenital hand deformities is an isolated incident, the outlook is generally good. Most children can learn to adjust to their differences. If the difference is part of the syndrome, the outlook depends on the type and extent of the condition.
Note that treatment does not “cure” the congenital hand deformities, but it does help improve the function and appearance of the hand. Accepting a positive attitude and a difference, on the part of children and parents, is important for the success of treatment, as well as for the healthy development of a child.