Biomechanical consequences of Zadek osteotomy in insertional achilles tendinopathy: A virtual surgical simulation study

Background: The Zadek osteotomy modified by Taylor (ZO) is a surgical technique used to treat insertional Achilles tendinopathy (IAT) by reducing the heel's prominence and elevating the Achilles tendon insertion. This study aims to analyze the biomechanical consequences of IAT after ZO using a virtual surgical simulation with a specific software. Methods: A retrospective analysis of 20 wtbearing computed tomography (WBCT) scans of IAT patients was conducted. Using Disior's BonelogicTM software, 3D models were created from WBCT images. Virtual ZO was performed on these models, and various biomechanical parameters were measured before and after the virtual osteotomy. Results: The virtual ZO showed significant statistical differences in the average of the calcaneal length (p < 0.001), Fowler Philips angle (p < 0.001), calcaneal pitch (p < 0.001), and the sagittal talocalcaneal angle (p < 0.001). Conclusions: The virtual ZO analysis suggests that this procedure can decrease the Fowler Philips angle, shorten the calcaneus, modifying specifically the sagittal alignment. Level of evidence: IV; case series. (c) 2024 European Foot and Ankle Society. Published by Elsevier Ltd. All rights are reserved, including those for text and data mining, AI training, and similar technologies.