What are the causes of bowleg and knock-knee?

Knock-knee can seen : In children from ages 2 to 5, and is often corrected naturally as children grow. However, the condition may continue or worsen with age, particularly when it is the result of a disease, such as rickets or obesity. Idiopathic is the term used to describe genu valgum that is congenital or has no known cause. Other systemic conditions may be associated, as schnyder central corneal dystrophy syndrom.