Supplementary Fibular-guided Growth in Treatment of Late-onset Blount Disease

Abstract

Purpose: Blount disease is due to an idiopathic defect in the posteromedial proximal tibial physis resulting in increasing bowing of the leg in addition to lateral knee thrust with lateral collateral ligament laxity. Our rationale is that Blount disease has a bony and ligamentous laxity element of the lateral collateral ligament that can be corrected simultaneously through hemiepiphysiodesis of the tibia and epiphysiodesis of proximal fibula physis by cannulated screws. Patients and Methods: This is a retrospective study conducted on 23 limbs with tibia vara treated between 2010 and 2017 followed up for 2 to 6 years. Ages ranged from 9 to 13 years with a late-onset type of Blount disease. We used a percutaneous transphyseal fully threaded screws traversing the proximal tibial lateral hemiepiphysis, and another screw inserted traversing the proximal fibular epiphysis. Results: There was a statistically significant improvement of the radiographic parameters, especially in the form of joint line congruence angle in both supine and standing positions. All patients were clinically and radiographically completely corrected without complications, except 1 patient with a surgical site superficial infection, treated medically. Conclusion: Fibular-guided growth surgery with lateral proximal tibia epiphysiodesis is a minimally invasive technique that improves the corrective power of hemiepyphysiodesis of the posterolateral compartment of the knee. Level of Evidence: Level IV, retrospective case series.