Infantile type of Blount's disease: considerations concerning etiopathogenesis and treatment.

The proper treatment of the infantile type of Blount's disease is still a controversial issue. We postulate the hypothesis of the etiopathogenesis of the infantile type of Blount's disease as a disease related to a dysplastic linkage between epiphysis and metaphysis. Therefore, considering the radiographic observations of a 26-month-old girl admitted in our department in 1986 with the infantile type of Blount's disease (type II Langenskiold--tibial femoral angle 24 degrees), the consequential optimal management of this condition is the need to apply a treatment consisting of the epiphyseal distraction capable of interrupting this dysplastic linkage, avoiding recurrences and damage to the growth cartilage. This child was treated with early, slow, and monocompartmental distraction by Ilizarov apparatus for 11 weeks. When the Ilizarov apparatus was removed, full recovery was achieved, the leg was clinically straight, and the mechanical axis was restored. The long-term follow-up (7 years) confirms this operation as a definitive treatment. It was less traumatic for the child, without recurrences or disorders of growth cartilage, supporting the dysplastic origin of infantile type of Blount's disease and the efficacy of this type of treatment.