Background Calcaneal osteotomy is used to correct hindfoot deformity. Pseudoaneurysms of the lateral plantar artery (LPA) have been reported following calcaneal osteotomy and are at risk of rupture. The vascular structures in close proximity to the calcaneal osteotomy have variable courses and branching patterns. However, there is little information on the “safe zone” during calcaneal osteotomy. This study aimed to identify the safe zone that avoids LPA injury during calcaneal osteotomy.Methods Enhanced computed tomography scans of 25 fresh cadaveric feet (13 male and 12 female specimens; mean age 79.0 years at time of death) were assessed. The specimens were injected with barium via the external iliac artery. A landmark line (line A) connecting the posterosuperior aspect of the calcaneal tuberosity and the origin of the plantar fascia was drawn and the shortest perpendicular distance between the LPA and line A was measured on sagittal images.Results The average perpendicular distance between the LPA and line A at its closest point was 15.2 ± 2.9 mm. In 2 feet (8.0%), the perpendicular distance between the LPA and line A at its closest point was very short (approximately 9 mm). In 18 of the 25 feet (72.0%), the point where the perpendicular distance from line A to the LPA was closest was the bifurcation of one of the medial calcaneal branches of the LPA, and in 7 feet (28.0%) the shortest perpendicular distance from line A to the LPA was the trifurcation of the LPA, medial plantar artery, and one of the medial calcaneal branches.Conclusion Calcaneal osteotomy performed more than 9 mm from line A could damage the LPA by overpenetration on the medial side. Calcaneal osteotomy on the medial side should be performed with caution to avoid iatrogenic injury to the LPA.Level of Evidence: IV, cadaveric study