Metatarsus adductus is thought to occur as a result of the infant's position inside the uterus. It can occur when the feet are bent inward, toward the midline, at the instep.

This is a relatively common disease affecting about one out of every 1,000 to 2,000 live births. Risk factors may include a condition called oligohydramnios where the mother does not produce enough amniotic fluid in the uterus.

• The front of the foot is bent inward (toward the midline) at the instep.
• The back of the foot and the ankles are normal. With a clubfoot, which is a different deformity, the foot will be pointed down and the ankle turned in as well.

Treatment depends on the severity of the deformity. Most children with metatarsus adductus can correct the deformity with normal use of their feet as they develop. These cases do not require any treatment.

For children who cannot do this, but who have an affected foot that can be easily manipulated to normal positioning, stretching exercises are all that is needed.

Rarely, this disease causes a rigid deformity that cannot be corrected with simple manipulation. In these cases, casting and even surgery may be required. Other diagnoses may need to be considered in these children. A pediatric orthopaedic surgeon should be involved in treating more severe deformities.