Hex-Based Correction of Complex Foot Deformity as a Result of Gustillo Iiib Fracture

In complex deformities of the mid- and hindfoot, there are limitations to acute correction due to soft tissue non-compliance, making acute lengthening of the foot impossible, and due to the risk of traction damage to tethered neurovascular structures. Gradual deformity correction using an external fixation device not only provides a safe passage for avoiding soft tissue complications and restoring the length of the foot but also makes the correction more accurate (Massobrio and Mora, Hexapod External Fixation Systems. Springer Nature, Switzerlend, 2021). The use of an orthopedic hexapod for the correction of complex deformities reduces the time of correction and increases the correction accuracy (Paley, Principles of Deformity Correction. Springer-Verlag, New York, 2005). The “multi-total residual” option of hexapod software (Myerson, Reconstructive Foot and Ankle Surgery: Management of Complications. M.S. Myerson. Elsevier, 2010) allows multiple fragments to move simultaneously. A clinical case of correction in a patient with complex post-traumatic mid- and hindfoot deformities, accompanied by chronic dislocations in the subtalar and Chopart joints, and bone defect is presented. At the first stage (36 days), using the Ortho-SUV Frame (OSF) orthopedic hexapod, the subtalar joint dislocation was eliminated. The pronounced (up to 60°) torsional component of hindfoot deformity could not be eliminated due to the impossibility of providing stability in the ankle and subtalar joints. Second stage (26 days) included hex-based elimination of the Chopart joint dislocation. Third stage was a triple joint fusion with 4.5 months of external fixation. Fourth stage included hindfoot osteotomy, residual deformity correction, and lengthening of calcaneus bone with the help of OSF. After 60 days, after the completion of the correction, the fifth stage was completed: transition to internal fixation. The weight-bearing ability was restored in 4 months. A good anatomical and functional result was obtained.