Double-calcaneal osteotomy with a unilateral rail external fixator for correction of pes planus: a case report.

A combination of the medial displacement calcaneal osteotomy with the Evans lateral column-lengthening osteotomy has been suggested when hindfoot valgus, forefoot abduction, and midtarsal joint instability are significant. However, the deforming forces must be flexible. The goal of this procedure is to restore alignment, stabilize the foot, and improve overall function. This double-calcaneal osteotomy addresses all components of the pes planus deformity. This article reports the use of a unilateral external fixator to callus distract the Evans calcaneal osteotomy while compressing the posterior medial calcaneal displacement osteotomy, which to the authors' knowledge has not been performed or reported in the literature. At the final post-operative visit of this clinical patient, the foot was rectus, and X-rays demonstrated an increased calcaneal inclination angle from 10 degrees preoperatively to 15 degrees postoperatively, a decreased talar declination angle from 39 degrees preoperatively to 26 degrees postoperatively, and the cuboid abduction angle decreased from 32 degrees preoperatively to 9 degrees postoperatively. The patient was pain free and extremely satisfied with the surgery, especially with the use of the external fixator.