Background: The Hexagonal external fixator (Hexapods) is known to have the ability to correct complex multi-planar
deformities faster than the Ilizarov apparatus. However, the difficulty of achieving deformity correction by Hexapods seems to limit its popularity.
Objective: This study aims to compare the advantages and disadvantages of Hexapods and Ilizarov in the gradual correction of complex tibial deformities.
Material and Method: A retrospective review was performed in patients with complex tibial deformities treated with Hexapods or with Ilizarov apparatus from 2000 to 2014. Magnitude of deformity, length of time in Hexapods or Ilizarov apparatus, Lengthening Index, and complications were recorded. Statistical analysis was used to compare the two methods.
Results: Six patients were treated with Ilizarov apparatus and seven patients were treated with Hexapods. Patients in
Hexapods group had more coronal plane angulation before surgery than in the Ilizarov group with statistical significance (p = 0.02). The differences of the sagittal and the axial plane angulations were not statistically significant. The difference of leg length was also not statistically significant. After completion of treatment, no statistical significance of residual deformities was found between the two methods. Lengthening Index had trends toward significance in Hexapods group (p = 0.051).
Conclusion: Computer-assisted Hexapods may reduce the Lengthening Index compared to the conventional Ilizarov method. The hexapods device could be beneficial for faster correction of complex deformity if the patients or family members understand how to manipulate the apparatus.

Keywords: Ilizarov method, External fixator, Apparatus, Computer-assisted hexapods, Ortho-SUV, Lengthening index, Complex tibial deformity