Knock knees, or genu valgum, is a condition where a person's knees touch while their ankles remain apart. This alignment can create an inward angle of the knees, which may be noticeable when standing or walking. It is common in children and often resolves naturally as they grow. In some cases, knock knees can persist into adulthood and may lead to discomfort or issues with walking. Factors contributing to this condition include genetics, obesity, and certain medical conditions. Treatment options vary and may include physical therapy, braces, or, in severe cases, surgery.