Metatarsus adductus is a foot deformity. The bones in the front half of the foot bend or turn in toward the body.
Metatarsus varus; Forefoot varus
Causes, incidence, and risk factors
Metatarsus adductus is thought to be caused by the infant's position inside the womb. Risks may include:
The baby's bottom pointed down in the womb (breech position)
The mother had a condition called oligohydramnios, in which she did not produce enough amniotic fluid
There may also be a family history of the condition.
Metatarsus adductus is a fairly common problem. It is one of the reasons why people develop "in-toeing."
Newborns with metatarsus adductus may also have a problem called developmental dysplasia of the hip (DDH), in which the thigh bone slips out of the hip socket.
The front of the foot is bent or angled in toward the middle of the foot. The back of the foot and the ankles are normal. About half of children with metatarsus adductus have the problem in both feet.
(Club foot is a different deformity. The foot is pointed down and the ankle is turned in.)
Signs and tests
Physical examination is all that is needed to diagnose metatarsus adductus.
A careful exam of the hip should also be done to rule out other causes of metatarsal adductus.
Treatment depends on how rigid the foot is when the doctor tries to straighten it.
If the foot is very flexible and easy to straighten or move in the other direction, no treatment may be needed. You child will be followed closely for a period of time.
In most children, the problem corrects itself as they use their feet normally. They don't need any further treatment.
If the problem does not improve or your child's foot is not flexible enough, other treatments will be tried:
Stretching exercises may be needed. These are done if the foot can be easily moved into a normal position. The family will be taught how to do these exercises at home.
Your child may need to wear a splint or special shoes, called reverse-last shoes, for most of the day. These shoes hold the foot in the correct position.
Rarely, your child will need to have a cast on the foot and leg. Casts work best if they are put on before your child is 8 months old. The casts will probably be changed every 1 - 2 weeks.
Surgery may be needed, but this is rare. Most of the time, your doctor will delay surgery until your child is between 4 and 6 years old.
A pediatric orthopaedic surgeon should be involved in treating more severe deformities.
The outcome is almost always excellent. Nearly all patients eventually have a normal looking and working foot.
A small number of infants with metatarsus adductus may have developmental dislocation of the hip.
Calling your health care provider
Call your health care provider if you are concerned about the appearance or flexibility of your infant's feet.
Hosalkar HS, Spiegel DA, Davidson RS. The foot and toes. In: Kliegman RM, Behrman RE, Jenson HB, Stanton BF, eds. Nelson Textbook of Pediatrics. 19th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 666.