Three-Dimensional (3D) Computed Tomographic (CT) Assessment of the Sustentaculum Tail to Find Distinctive Characteristics: Implications for Surgery

BACKGROUND: With the complexity of calcaneal fracture (CF) increasing, its treatment has changed to include inserting the screw used to secure the facies articular posterior into the sustentaculum tail (ST). Some research progress has been made in this area, but there has been little in-depth research on the anatomical morphology of the sustentaculum tail, which is necessary for clinical surgery, and more information about Chinese anatomic characteristics and improved surgical techniques for CF are needed. MATERIAL/METHODS: This anatomical study, based on a three-dimensional (3D) computed tomographic (CT) reconstruction technique, included 287 dry calcaneus, consisting of 144 left and 143 right calcaneus. The images were reconstructed in 3D after CT scanning. Seven subjects were enrolled (L and R): (1) The vertical distance from inside the sustentaculum tail (IST) to inside the facies articularis talaris posterior; (2) The vertical distance from IST to the outside facies articularis talaris posterior; (3) The thickness of sulcus calcaneal nadir; (4) The distance from IST to processus medislis tuberis calcaneus; (5) The distance from IST to calcaneal posterosuperior tuber; (6) The angle of the prolate axial intersection between ST and calcaneus on the normal superior as ∠α; and (7) The angle of the prolate axial intersection between ST and calcaneus on the normal posterior as ∠β. All measurement results were analyzed by SPSS 22.0. RESULTS: Based on morphological classification, the average length of AB, AC, AE, and AF on left ST were 16.956±1.391 mm, 37.803±2.525 mm, 43.244±3.617 mm, and 51.113±4.455 mm, respectively. Among the others, ∠β was 81.227±6.317 mm on the left and 74.581±9.008 mm on the right (P<0.05). CONCLUSIONS: These results suggest better ways to treat the special characteristics and to reduce the risk of CF surgery.