Blount disease: an update.

Blount disease is a developmental disorder associated with childhood obesity. Based on whether the deformity is first noted before or after 4 years of age, early-onset and late-onset forms of Blount disease have been described. Besides physeal abnormalities of the proximal tibia, compensatory changes in the intra-articular morphology of the medial compartment of the affected knee are often noted on MRI scan. Both guided growth and acute and gradual correction via a proximal tibial osteotomy have roles in the surgical management of these patients. In order to optimize clinical outcome, frequent follow-up until skeletal maturity is recommended.