Depression of the medial tibial plateau in early-onset Blount disease: myth or reality?

Abstract

Patients with severe early-onset Blount disease (Langenskiold III or greater) often have the radiographic appearance of depression of the medial tibial plateau and delayed ossification of the epiphysis, adjacent physis, and metaphysis. Schoenecker and other authors recommended elevation of the medial plateau of the tibia for correction of this deformity. The purpose of this study was to assess the nature of the medial proximal tibia in these severe cases. Eight girls and two boys (17 tibiae) with severe early-onset Blount disease had standing radiographs and magnetic resonance imaging (MRI) evaluation. Average patient age was 5.8 years (range, 3-8 years). Eleven knees in eight patients underwent arthrography at the time of surgical correction of deformity. No tibia had MRI or arthrographic evidence of medial tibial joint "depression." The "empty" radiographic space was occupied by cartilage-density material. A smooth dye contour without pooling parallel to the femoral condyles was noted arthrographically in all instances. These findings do not support the concept of routine joint elevation in the correction of severe deformity associated with early-onset Blount disease.