A quantitative three-dimensional analysis of posterior facet displacement in Sanders Type II and III intra-articular calcaneal fractures

作者：Xinzhe Ma, Shibo Zhai, S Zhang, Pengfei Shen, Luqin Di, W Chen, Zhiyong Hou, Lijie Ma · 发表于：Frontiers in Surgery · 年份：2026 · DOI：10.3389/fsurg.2026.1839210 · 研究领域：Foot and Ankle Surgery、Spinal Fractures and Fixation Techniques、Orthopedic Surgery and Rehabilitation

Objective: To quantify the three-dimensional (3D) displacement characteristics of the posterior facet fragment in Sanders type II and III intra-articular calcaneal fractures (IACFs) caused by falls from height, thereby providing a quantitative anatomical reference for reduction planning. Methods: We retrospectively analyzed CT data from 71 patients with closed Sanders type II/III IACFs. Mimics and 3-matic software were utilized for 3D reconstruction and simulated reduction. The translational and rotational changes of the fragment's geometric center were measured before and after reduction. Results: < 0.05). Predominant translations were lateral (4.55 ± 3.16 mm) and inferior (3.81 ± 3.13 mm), while posterior translation was minor. Primary rotational deformities included axial plane internal rotation (17.62 ± 14.57°) and sagittal plane anterior tilt (12.29 ± 13.42°). Coronal plane varus (4.61 ± 13.97°) was minimal but exhibited high variability, indicating significant instability. Conclusion: Posterior facet fragments primarily displace inferolaterally with significant internal rotation (∼17.62°) and anterior tilt. These findings suggest that rotational malalignment, particularly axial-plane internal rotation and sagittal-plane anterior tilt, may be an important but easily overlooked component of posterior facet displacement. The results may provide a quantitative anatomical reference for preoperative planning and intraoperative assessment of reduction, although further biomech...