May also be called: Knock-Knees Genu valgum (GEE-noo VAL-gum) is a condition in which the upper legs angle inward and the knees touch while the ankles are spread apart. More to Know Genu valgum is a common condition in children and is almost always a normal part of a child's development. Because of the way their bodies are positioned in the uterus, most babies are born bowlegged and stay that way until about age 2 or 3. After that, their legs turn inward and take on a knock-kneed appearance until they're about 7 or 8 years old. At that time, the legs generally assume their normal alignment. In rare cases, genu valgum that develops later (at around age 6) can be a sign of an underlying bone disease. Treatment for genu valgum is almost never required as the legs usually straighten out on their own. Severe knock-knees or knock-knees that are more pronounced on one side sometimes require treatment with braces that straighten the legs. Surgery to correct genu valgum is usually only done if the condition is severe and causes pain or difficulty walking. Keep in Mind In just about every case, genu valgum is a harmless condition that will eventually clear up on its own. When treatment is necessary, the results usually are very good and the condition is corrected with no long-term issues to worry about. All A to Z dictionary entries are regularly reviewed by KidsHealth medical experts. Back to Articles Related Articles Blount Disease Blount disease is a growth disorder that causes the bones of the lower leg to bow outward. This gets worse if it's not treated, so early diagnosis is very important. Read More Blount Disease Blount disease is a growth disorder that affects the bones of the lower leg. It causes bowing of the leg below the knee, which gets worse if it's not treated. Read More Common Childhood Orthopedic Conditions Flatfeet, toe walking, pigeon toes, bowlegs, and knock-knees. Lots of kids have these common orthopedic conditions, but are they medical problems that can and should be corrected? Read More Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor. © 1995-2021 KidsHealth®. All rights reserved. Images provided by The Nemours Foundation, iStock, Getty Images, Veer, Shutterstock, and Clipart.com.