Birth defects

• Birth defects can cause disabilities and even death.
• Alcohol and drug use while pregnant can cause birth defects.
• Ask your provider what you can do to prevent birth defects.

Clubfoot is a word used to describe a foot defect present at birth. The defect can be mild or severe, and it can involve one foot or both. The medical term for clubfoot is talipes equinovarus. There also are other milder foot defects that are not as severe as clubfoot.

How common is clubfoot?
Clubfoot is one of the most common birth defects. More than 4,000 babies (about 1 in 1,000) are born with clubfoot in the United States each year (1, 2). Boys are affected twice as often as girls (1, 2). Mild foot defects are even more common than clubfoot.

How does clubfoot affect a child?
An affected foot points downward and twists inward. If both feet are “clubbed,” the soles of the feet may face each other. The foot bones, ankle joints, and muscles and ligaments of the foot may be abnormal.

Clubfoot is not painful, and it doesn’t bother the baby until he begins to stand and walk. Untreated, the ankle remains twisted, and the foot can’t move up and down as it normally would. If both feet are affected (which occurs in about 50 percent of cases) (1), the child walks on the sides or even on the top part of the feet instead of the soles. The part walked on may become infected and develop a large, hard callus. Painful arthritic changes also develop.

If only one foot is affected, that foot and calf are smaller than those on the other side.

What are some other common foot defects?
Calcaneovalgus and metatarsus adductus are common, mild foot defects.

• Calcaneovalgus: The baby’s foot bends sharply at the ankle so that the foot points upward and outward. In many cases, the top of the foot can touch the shinbone. Calcaneovalgus usually goes away without treatment in the first few months of life, and there are no lasting effects (3).
• Metatarsus adductus: The front part of the foot turns inward, causing the child to walk with his toes pointed in. Most affected children require no treatment, as the condition often resolves itself. However, severe cases are treated with special shoes or casts, usually between 6 and 9 months of age (4).

How are foot defects diagnosed?
Clubfoot and certain other foot defects generally can be recognized during the newborn examination. These defects usually can be diagnosed with a physical examination alone, though occasionally the provider may recommend additional tests, such as X-rays.

Clubfoot sometimes is diagnosed before birth, during an ultrasound. Though the disorder cannot be treated before birth, parents have a chance to locate an orthopedic surgeon and learn about treatment options.

How is clubfoot treated?
Babies are generally treated with non-surgical approaches. Most involve some form of manipulation, casts, taping and splinting. These approaches have greatly reduced the need for major surgical repairs, which were often associated with long-term complications, such as foot and ankle pain and stiffness (2). A baby with clubfoot should be treated by an orthopedic surgeon who is experienced in dealing with clubfoot and can discuss the various treatment options with parents.

The most common approach for treating clubfoot in the United States uses manipulation and casting, which usually corrects clubfoot in 2 to 3 months (1, 2). Ideally, treatment should begin in the first few weeks of life (2). At this age, the ligaments and tendons in the foot are very flexible and respond well to treatment. Studies suggest that this approach also can be successful in treating children older than 1 year with uncorrected clubfoot (2).

The doctor gently manipulates the baby’s foot and then puts it in a plaster cast to hold it in the corrected position. The cast extends from the upper thigh down to the toes. Every 5 to 7 days, the doctor takes off the cast, manipulates the foot and puts on a new cast. Each manipulation and casting brings the foot closer to normal. Several casts usually are needed to correct the clubfoot (5). Often children need to wear a brace for several months after treatment is completed to assure that the foot remains in good position.

Another treatment approach is to have a physical therapist and the family manipulate the baby’s foot daily for 2 months, then less frequently until 6 months of age (2). After each session, the baby’s foot is taped to hold the correction in place. When the physical therapy is completed, the baby wears splints at night until walking age. Some providers combine elements of both approaches.

With early expert treatment, most children with even severe clubfoot can grow up to wear regular shoes, take part in sports and lead full, active lives. However, the affected foot is generally 1 to 1½ shoe sizes smaller than the unaffected one, and the calf appears slightly thinner. The differences are minimal and have no impact on function.

What causes clubfoot and other foot defects?
The exact causes of clubfoot are not known. In the past, doctors thought that the baby’s feet were twisted or cramped because of the way the baby lay in its mother’s womb. This is true of some foot abnormalities that correct themselves after birth (including calcaneovalgus and mild metatarsus adductus).

Scientists now believe that both genetic and environmental factors contribute to clubfoot. Environmental factors may include infection, drug use and cigarette smoking. One study found that women with a family history of clubfoot who smoked cigarettes during pregnancy had a 20-fold increased risk of having an affected baby (6).

Most children with clubfoot have no other birth defects, though occasionally other defects do occur. In a few cases, clubfoot occurs as part of a syndrome that includes a number of birth defects. For example, children with spina bifida (open spine) sometimes have a form of clubfoot. This is caused by damaged spinal nerves that affect the legs. In other cases, feet that are normal at birth may become twisted as a result of muscle or nerve diseases.

Can clubfoot be prevented?
There is no way to prevent clubfoot at this time. However, pregnant women should not smoke, especially if they have a family history of clubfoot. (Smoking also increases the risk of having a low-birthweight or premature baby, as well as other pregnancy complications.)

Genetic counseling can help parents understand the odds of having a child with clubfoot. Generally, if a child has an isolated clubfoot (no other birth defects present), the recurrence risk in another pregnancy is low (about 5 percent), but substantially greater than the risk in the general population (1).

Does the March of Dimes support research on clubfoot?
Yes. In 2008, a March of Dimes grantee at Washington University School of Medicine in St. Louis was part of the team that identified the first gene linked with clubfoot in humans (7). The gene, PITX1, plays a critical role in early development of the legs. A better understanding of the genetic factors that contribute to clubfoot may eventually lead to new ways to prevent and treat the disorder. March of Dimes researchers also are studying how an unborn baby’s muscles, bones and nerves grow, and the genetic and environmental factors that influence them, for insight into the causes and prevention of clubfoot and other birth defects.

References

1. American Academy of Orthopaedic Surgeons. (2007). Children’s clubfoot: Treatment with casting or operation? Retrieved May 19, 2009 from: orthoinfo.aaos.org.
2. Dobbs, M.B., & Gurnett, C.A. (2009). Update on clubfoot: Etiology and treatment. Clinical Orthopaedics and Related Research, 467(5), 1146-1153.
3. Duke University Department of Orthopaedics. (2009). Calcaneovalgus foot. Retrieved May 19, 2009 from: wheelessonline.com/ortho/calcaneovalgus_foot.
4. American Academy of Orthopaedic Surgeons. (2009). Intoeing. Retrieved May 19, 2009 from: orthoinfo.aaos.org..
5. Richards, B.S., Faulks, S., Rathjen, K.E., Karol, L.A., Johnston, C.E., et al. (2008). A comparison of two nonoperative methods of idiopathic clubfoot correction: The Ponseti method and the French functional (physiotherapy) method. The Journal of Bone and Joint Surgery (11), 2313-2321.
6. Honein, M.A., Paulozzi, L.J. & Moore, C.A. (2000). Family history, maternal smoking and clubfoot: An indication of a gene-environment interaction. American Journal of Epidemiology, 152(7), 658-665.
7. Gurnett, C.A., Alaee, F., Kruse, L.M., Desruisseau, D.M., Hecht, J.T., et al. (2008). Asymmetric lower-limb malformations in individuals with homeobox PITX1 mutation. American Journal of Human Genetics, 83, 616-622.

January 2010