Tibia vara: osteochondrosis deformans tibiae. Blount's disease.

Tibia vara is a deformity of abrupt angulation into varus below the knee and inward rotation of the tibia. The condition appears as an infantile type manifesting itself at age one to three years, and as an adolescent type. Although the etiology of the infantile type is obscure, cartilage changes in the medial part of the growth plate and the epiphysis suggest that is belongs in the category of osteochondroses. The adolescent type, a separate entity secondary to infection or trauma, is not discussed here. Untreated infantile tibia vara will likely worsen and progress to severe bowleg. It is generally agreed that early osteotomy, adequately performed before the age of eight years, ordinarily results in a cure; however, when treatment is delayed to the age of nine or older, partial epiphyseal arrest often occurs. Simple osteotomy is then followed by recurrence, after which other operative measures are necessary.