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Posterior ankle disorders pose a diagnostic and therapeutic challenge to surgeons, owing to the deep location of the anatomical structures and lesions within and around the joint. Arthroscopy has therefore become a valuable tool for the diagnosis and treatment of posterior ankle disor-ders.2,5-7,9,11,13,17,20 Although the use of a 2-portal endoscopic approach to the posterior aspect of the ankle has been reported,17 the safety of posterior ankle arthroscopy remains controversial.1,3,6,9,14,19 Many studies discourage the use of posteromedial portals because of the increased risk of neuro-vascular injury.1,3,6,9,14,19 Clinical studies using posterior ankle arthroscopy have described the complication rate of injury to the sural nerve or tibial nerve rate in the range of 0 % to 8.3%.2,5,6,7,9-11,13 As such, surgeons are still searching for reproducibility in operative techniques in order to minimize the risk of iatrogenic injury during ankle arthroscopy. Various anatomical studies have assessed the safety, efficacy, and anatomical relationships associated with placement of the posterior portals, describing the distance between posterior portals, neurovascular structures, and the instruments required for surgery.4,8,12,15,16,18 However, during posterior ankle arthroscopy, it is difficult to confirm the distance between the instruments and the neurovascular structures, because it is necessary to first remove the fatty tissue and the joint capsule to reach the target. This is technically demanding, and until the posterior structures are properly identified, there is potential risk to the posterior neurovas-cular structures. The purpose of this study was to evaluate the anatomical relationship between the position of pre-sumed posterior portals and the underlying neurovascula