Knock knees are condition in which the knees touch, but the ankles do not touch. The legs turn inward.
Infants start out with bowlegs because of their folded position while in their mother's womb. The legs begin to straighten once the child starts to walk (at about 12 to 18 months). By age 3, the child becomes knock-kneed. When the child stands, the knees touch but the ankles are apart.
By puberty, the legs straighten out and most children can stand with the knees and ankles touching (without forcing the position).
Knock knees can also develop as a result of a medical problem or disease, such as:
Knock knees are not treated in most cases.
If the problem continues after age 7, the child may use a night brace. This brace is attached to a shoe.
Surgery may be considered for knock knees that are severe and continue beyond late childhood.
Children normally outgrow knock knees without treatment, unless it is caused by a disease.
If surgery is needed, the results are most often good.
Complications may include:
Call your provider if you think your child has knock knees.
There is no known prevention for normal knock knees.
Published Date: October 02, 2020
Published By: Neil K. Kaneshiro, MD, MHA, Clinical Professor of Pediatrics, University of Washington School of Medicine, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
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