Treatment of Blount disease: a comparison between the multiaxial correction system and other external fixators.

BACKGROUND: Many surgical procedures have been proposed for treatment of Blount disease (tibia vara). Gradual correction of Blount disease has been described with both unilateral and circular external fixators. The purpose of this study was to compare the clinical and radiographic results of gradual correction for severe or recurrent Blount disease using the Biomet Multi-Axial Correction (MAC; Biomet Trauma, Parsippany, NJ) external fixator to our historical controls using other devices (such as the Ilizarov and Garche T-clamp).

METHODS: A total of 58 corrections were performed on the 54 limbs in 38 patients. Charts were analyzed to evaluate the presence of complications during the course of external fixator treatment. The tibiofemoral, anatomic medial proximal tibial, and proximal posterior tibial angles were measured on radiographs taken before application of the external fixator and after removal to compare the correction achieved by the MAC fixator and the other fixators.

RESULTS: The mean values for the tibiofemoral angle, anatomic medial proximal tibial angle, and proximal posterior tibial angle were similar between the 2 groups after treatment and at follow up. The rate of complications between the 2 groups was also not significantly different.

CONCLUSIONS: The MAC external fixator provides an acceptable alternative for gradual correction of Blount disease.

LEVEL OF EVIDENCE: Level III.