Curvature of the legs is, in most cases, an expected stage of a child's development. In infancy there is a gap between the knees (bow legs); once the child starts walking and grows, this appearance turns into knock knees and straightens out towards school age.

What to expect at each age

Period Expected appearance
Infancy – first steps Mild bow legs
Early childhood Bowing decreases, shifts towards knock knees
Preschool – school age Knock-knee appearance decreases on its own

These transitions happen at a different pace in every child; two children of the same age are not expected to look alike.

Situations that call for assessment

  • Curvature that is one-sided
  • Increasing with age, or not straightening at all
  • Marked and progressively increasing asymmetry
  • Pain, limping, frequent falls
  • Short stature accompanying it
  • A similar, unresolved history in the family

What the doctor assesses

During the examination, leg alignment, the way the child walks and the growth curve are reviewed together. If considered necessary, an X-ray and tests related to vitamin D may be requested. The aim is to distinguish the expected developmental change from one that has an underlying cause.

Common misconceptions

Correcting the curvature with a baby walker, leg binding, tight swaddling or special shoes is not a demonstrated approach. Baby walkers are also not recommended because of the risk of accidents.