Foot and ankle: Metatarsus adductus

What is metatarsus adductus?

Metatarsus adductus is a common foot condition in babies and young children. Normally, the foot has a straight outside border. In metatarsus adductus, the outside border of the foot curves inwards, resulting in a bean-shaped appearance.

Metatarsus adductus is thought to be related to the position of the fetus during pregnancy and can affect one or both feet. A baby born with metatarsus adductus should have a careful hip examination since the development of the hip joint can also be affected by the position of the fetus before birth.

In most babies, affected feet stay flexible (can be stretched straight), and the condition resolves over the first three to five years without treatment. Metatarsus adductus is a common problem with more than 95% resolving on their own. Mild residual metatarsus adductus may be present until five years of age.

Treatment of metatarsus adductus

Some babies and young children with metatarsus adductus need assessment and monitoring by the child’s health-care provider or physiotherapist. Gentle stretches and exercises may help to straighten the foot. These exercises should be performed regularly. Exercises are most effective when the baby or child is relaxed and should never be painful for them. In rare cases treatment may be needed. This may consist of a series of casts, special braces, straight last shoes (shoes made without a curve in the bottom of the shoe) or shoe inserts.

If you are concerned that your child's foot remains stiff or is not improving, talk to their health-care provider or physiotherapist. Serial long-leg casting for rigid deformity may be needed (where the front part of the foot cannot be easily moved outwards to create a straight outside border).

Stretches and exercises

• Midfoot stretch

  

  Gently move the side of your baby’s foot outwards so it is straight. This may be held for 20 to 30 seconds, or longer if your baby is comfortable.

• Muscle stimulation exercise

  

  Gently stroke the outside and front of your baby’s foot and lower leg to encourage the foot into a normal position.

Reference

Mosca, V.S. (2014). Principles and Management of Pediatric Foot and Ankle Deformities and Malformations. Wolters Kluwer Health. p. 95.