A child with knock knees has knees that curve inward. It's most noticeable when the child is standing — the knees touch and the ankles are apart. Knock knees usually go away on their own by the time a child is 8 years old. 

Here's how to care for your child.

• Your child can run, play, walk barefoot, do sports, and participate in all other regular activities unless your healthcare provider tells you otherwise.
• Be sure your child wears supportive shoes that fit well.
• If treatment is needed, follow your healthcare provider's instructions. They may recommend:
  • Going for physical therapy
  • Doing stretching and strengthening exercises
  • Seeing an orthopedic healthcare provider (a bones and joints specialist)

Your child has:

• Pain, weakness, limping, or trouble running
• Worsening of knock knees
• Knock knees that did not get better by the time the healthcare provider told you they would

What causes knock knees? The way a child's bones grow when they are about 2–4 years old can make the knees turn inward.

What happens if knock knees don't get better? Often, knock knees go away on their own. Usually, the legs start to straighten around age 4, and knock knees go away around the time a child is 7 or 8. Your healthcare provider may need to repeat previous exams to make sure your child's legs are getting better as they grow. Some kids need to see an orthopedic healthcare provider if the legs don't straighten on their own.

If knock knees are painful or don't improve by around age 10, healthcare providers might suggest doing surgery to straighten the legs.

Can knock knees be a sign of something more serious? Most of the time, knock knees are not a sign of a more serious condition. Rarely, if knock knees don't go away or if they start after age 4, it may be a sign of a health problem, such as a fracture that hasn't healed correctly or a problem with the way the bones are formed. Sometimes having extra weight can lead to knock knees.