Bowlegs and knock-knees

Disclaimer: This fact sheet is for education purposes only. Please consult with your doctor or other health professional to make sure this information is right for your child.

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What are bowlegs and what is the cause?

Bowing of the legs (called genu varum) is when the legs curve out like a bow. When the feet are together, there is a gap between the knees.

Bowing is an expected growth pattern in the legs of babies and toddlers. The bowing is caused by the position of the baby’s legs in the womb. The bowing may also give your child a pigeon-toed appearance. Pigeon-toe is when the toes point in towards each other).

Is any treatment needed?

Children’s legs naturally lose their bowed shape at around 3 years of age.

If you are worried about your child’s legs, you can take photographs of them every six months to record the changes. Your child should see a doctor if:

  • The bowing is getting worse
  • One side is more bowed than the other

Braces or special shoes will not help straighten your child’s legs.

Sometimes bowing can be caused by illnesses that need to be treated. The doctor can find these by looking at your child. X-rays are not always needed.

What are knock-knees?

Knock-knees are the opposite of bowlegs. Knock-knees are when the legs curve in, so the knees are touching and the ankles are apart.

At 2-3 years of age your child may begin to become knock-kneed (called genu valgum). You may notice this more between 3-4 years of age.. It should not be painful.

Knock knees is an expected growth pattern in children. By 7-8 years of age the legs usually straighten. Some children remain knock kneed until they are teenagers. Many adults remain slightly knock kneed.

Is any treatment needed?

Treatment is rarely needed. The knock knees will straighten as your child grows. Splints are not recommended. In very rare cases, treatment may be needed for teenagers with continued, severe knock-knees.

If you are concerned about your child’s legs, you can take photographs every six months to record the changes. Your child should see a doctor if:

  • The knock-knees are getting worse
  • One leg is worse than the other
  • Your child has a limp or pain. 


  • Bowing is common in children under two.
  • Knock-knees are common in children aged three to four.
  • See your GP if your child develops a limp, pain, or one leg is worse or different to the other.
The Children's Hospital at Westmead
Sydney Children's Hospital, Randwick
Hunter New England Kids Health

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