Bowlegs and Knock-Knees

What are bowlegs and knock-knees?

Babies and young children often have knees and legs that look awkward. Two types of problems at this age are bowlegs and knock-knees. Both of these are fairly common in babies and young children.

If a child has bowlegs, the legs bow outwards when she or he stands. When your child stands with his or her feet together, the knees will be far apart. With knock-knees the lower legs angle out, so that the ankles are far apart when the knees touch. Bowlegs are very easy to see at 12 to 18 months when your child starts to stand and walk. Standing and walking helps the legs to straighten. Knock-knees usually are noticed later between the ages of 3 and 6.

What is the cause?

A baby's legs are folded up before they are born. This can cause them to be bowlegged at first. Severely bowed legs can be caused by rickets or Blount's disease. Both are rare conditions. Rickets is typically caused by not getting enough or being able to properly use vitamin D. Blount's disease is a growth disorder of the shinbone that causes changes in the lower legs.

The most common cause of knock knees is a result of overcorrection of bowlegs. This is common and normal between 3 and 5 years of age. There may be other problems that can cause bowlegs or knock-knees, including problems with the bones, kidneys, infections, and injuries.

Rarely are bowlegs or knock-knees the result of a disease.

How long does it last?

The bowlegs are usually gone by age 2. At this point most children start to have a slight knock-kneed look. It is a normal part of development. The legs start to straighten out at age 5 or 6 as your child grows. The legs will typically look normal by age 7 to 10. During the early teenage years, your child will usually be able to stand normally with the knees and ankles touching.

What is the treatment?

Most children will outgrow knock-knees and bowlegs without any special treatments. However, in severe cases, your provider may want your child to see a bone specialist called an orthopedist.

In rare cases surgery may be recommended, especially if the problem continues as your child grows older. Sometimes braces or special shoes to help straighten the legs may be used, although not all providers think this treatment is needed.

When should I call my child's healthcare provider?

Call your child's healthcare if you have questions or concerns about your child's legs.

Your child should see a healthcare provider if:

• the bowing is getting worse after 2 years of age
• one leg is bowed more than the other
• the knock-knees persist after 7 years of age
• your child is having increasing pain or problems because of the angle of the knees and legs
• your child has severe intoeing (toes pointing in when walking)
• your child is unusually short for his age or has problems standing up straight.