Bow-legs and knock knees factsheet


Bowlegs and knock-knees are a normal part of leg development in babies and toddlers and should start to correct themselves as your child grows.

Bowlegs are when the legs curve outwards like a bow and arrow. 

They are caused by the position of your baby’s legs during pregnancy.

Knock-knees are when the knees turn inwards, sometimes touching. 

They are caused by normal bone development from about 2-4 years of age. They can also be caused by:

  • healing fractures in the bone
  • conditions like hip dysplasia
  • rickets – a bone growth condition caused by not having enough calcium or vitamin D.

Some children remain knock-kneed until they are teenagers. Many adults remain slightly knock-kneed.

Signs and symptoms

Bow-legs and knock-knees should not cause any pain.


Bowlegs cause children's legs to curve outward. Children with bowlegs stand with their feet apart, and their knees do not touch. They may also have pigeon toes, where their feet turn inward.


Knock-knees in children cause difficulty standing with feet together, as knees push inwards and touch. It usually appears between ages 2-3 and becomes more noticeable at ages 3-4.



Your doctor will diagnose bowlegs by physically examining your child’s legs. 

If your child is over two years old, the doctor will measure their legs and watch their walking pattern. 

X-rays and blood tests may also be ordered to see if there are any other conditions.


Your doctors can diagnose knock-knees by looking at the position of your child's legs, knees, and ankles. They may measure the distance between the ankles to see how severe the condition is. 

X-rays are only needed if your child is over seven years old or has uneven legs. 

If your child is under seven and has no trouble moving, an x-ray may not be necessary.


Braces, splints, or special shoes do not help straighten out bowlegs or knock-knees in children.

Bowlegs will start to straighten out around three years old. Knock-knees may take a little longer to correct themselves. 

In extremely rare cases, further treatment may be needed for children who have severe knock-knees into their teenage years. 

If you have concerns about your child's leg development, you can take a photo of their legs every six months to track any changes.

Check in again with your doctor if:

  • the bowlegs or knock-knees are getting worse
  • one leg is worse than the other
  • your child has a limp or pain. 
Last updated Tuesday 19th March 2024


This factsheet is provided for general information only. It does not constitute health advice and should not be used to diagnose or treat any health condition.

Please consult with your doctor or other health professional to make sure this information is right for you and/or your child.

The Sydney Children’s Hospitals Network does not accept responsibility for inaccuracies or omissions, the interpretation of the information, or for success or appropriateness of any treatment described in the factsheet.

© Sydney Children’s Hospitals Network 2024