Review Question - QID 216479

In a 2½-year-old patient with Langenskiold type I Blount's Disease, initial treatment with a knee-ankle-foot orthosis (KAFO) would be appropriate.

Infantile Blount's disease is progressive, pathologic genu varum centered at the tibia in children 2 to 5 years of age. Clinically, patients present with a genu varum/flexion/internal rotation deformity. The diagnosis is confirmed radiographically with an increased metaphyseal-diaphyseal angle. Treatment ranges from bracing to surgery depending on patient age, severity of deformity, and presence of a physeal bar. Brace treatment with KAFO is indicated with stage I and II in children 2-3 years of age. Bracing should be continued for approximately 2 years for resolution of bony changes. Outcomes with KAFO are improved if the disease is unilateral while poorer results are associated with obesity and bilaterality.

Castañeda et al. retrospectively reviewed their experience with hemiepiphysiodesis and physeal stapling for the correction of angular deformity. They reported correction of the mechanical axis deformity from a mean of -19 degrees pre-operatively to a mean of -16 degrees. They concluded that hemiepiphysiodesis is effective in preventing the progression of deformity in patients with Blount disease.

Birch et al. reviewed progressive tibial varus deformity in otherwise healthy children and adolescents. They report that if the condition remains unresolved, it can lead to progressive varus deformity, with or without associated deformities of the distal femur and/or tibia, leg length inequality, and significant articular distortion, leading to premature osteoarthritis of the knee. They concluded that early stages of infantile Blount's disease may respond to nonsurgical treatment.

Illustration A depicts the Langenskiold classification of Blount's Disease

Incorrect Answers:
Answer 1: Patients 2-3 years of age with a Langenskiold type I-II deformity are candidates for bracing.
Answer 3: Proximal tibia/fibula valgus osteotomy is indicated in stage I and II in children >3 years, stage III, IV, V, VI, age ≥4 years (all stages), failure of brace treatment, progressive deformity, or metaphyseal-diaphyseal angles >20 degrees
Answer 4: Physeal bar resection is indicated in patients with at least 4 years of growth remaining and is often performed together with osteotomy
Answer 5: Gradual angular correction with osteotomy and distraction osteogenesis external fixation would not be indicated in a child <3 years of age with Langenskiold type I