Outcomes of the Extended Z-Cut Osteotomy for Correction of Adult Acquired Flatfoot Deformity.

Background: Medial displacement calcaneus tuberosity osteotomy and anterior process lengthening calcaneus osteotomy are traditional single-plane osteotomy techniques used in adult acquired flatfoot deformity reconstruction. More recently, 3-plane step-cut osteotomies were described for each of these and shown to offer improved rotational stability via the horizontal limb. However, a major technical challenge is achieving a sufficiently long horizontal limb to correct deformity through lengthening without losing bony apposition.