Controlled Double Gradual Opening Osteotomy for the Treatment of Severe Varus of the Knee-Blount's Disease.

Varus deformity of the knee can lead to early degeneration of the medial tibiofemoral joint. Pediatric patients can be pathologically affected with this deformity known as Blount disease. The cause of this pathology is still uncertain, but some risk factors are well established, such as obesity and family history. The diagnosis is made through clinical history, physical examination, and the radiographic analysis after the age of 2.5 years. The analysis of the metaphyseal-diaphyseal angle, described by Levine and Drennan, is also commonly used for prognosis. When this angle is greater than 16°, it is considered to be grossly abnormal. Possible options for correcting the generated angular deformity are epiphysiodesis, osteotomy (acute or gradual correction), and gradual correction by distraction of the physis. In this surgical technique, we performed a double tibial osteotomy with controlled gradual opening using monolateral external fixator (Orthofix, Verona, Italy). Our technique proved to be an effective way to correct the adolescent tibia vara and is practical and reproducible. Moreover, the use of gradual opening osteotomy allowed a more accurate outcome.