METHODS: We retrospectively collected the calcaneus computed tomography (CT) scans of 180 adults, DICOM-formatted CT-scan images of each patient were imported into Mimics software to establish calcaneus model. Virtual screws were placed on the lateral of the posterior talar articular surface (PTAS), the lateral edge of the anterior process of calcaneus (APC), and the calcaneal tuberosity, respectively, the trajectory and size of the screws were calculated.
RESULTS: The mean maximum diameter of the PTAS screw was 42.20 ± 3.71 mm. The vertical distance between the midpoint of the APC optimal screw trajectory and the lowest point of the tarsal sinus was 10.67 ± 1.84 mm, and the distance between the midpoint of the APC optimal screw trajectory and the calcaneocuboid joint was 5 mm ~ 19.81 ± 2.08 mm. The mean maximum lengths of APC screws was 44.69 ± 4.81 mm, and the Angle between the screw and the coronal plane of the calcaneus from proximal to distal was 4.72°±2.15° to 20.52°±3.77°. The optimal point of the maximum diameter of the calcaneal tuberosity screw was located at the lateral border of the achilles tendon endpoint. The mean maximum diameters of calcaneal tuberosity screws was 4.46 ± 0.85 mm, the mean maximum lengths of screws was 65.31 ± 4.76 mm. We found gender-dependent differences for the mean maximum diameter and the maximum length of the three screws.
CONCLUSIONS: The study provides effective positioning for percutaneous screw fixation of calcaneal fractures. For safer and more efficient screw placement, we suggest individualised preoperative 3D reconstruction simulations. Further biomechanical studies are needed to verify the function of the screw.
方法:我们回顾性收集了180名成人的跟骨计算机断层扫描(CT)扫描,将每个患者的DICOM格式的CT扫描图像导入Mimics软件以建立跟骨模型。虚拟螺钉放置在距骨后关节面(PTAS)的外侧,跟骨前突(APC)的外侧边缘,跟骨结节,分别,计算了螺钉的轨迹和尺寸。
结果:PTAS螺钉的平均最大直径为42.20±3.71mm。APC最佳螺钉运动轨迹的中点与骶骨窦最低点的垂直距离为10.67±1.84mm,APC最佳螺钉轨迹的中点与跟骨关节之间的距离为5mm〜19.81±2.08mm。APC螺钉的平均最大长度为44.69±4.81mm,螺钉与跟骨冠状面之间的夹角从近端到远端为4.72°±2.15°至20.52°±3.77°。跟骨结节螺钉最大直径的最佳点位于跟腱端点的外侧边界。跟骨结节螺钉的平均最大直径为4.46±0.85mm,螺钉的平均最大长度为65.31±4.76mm.我们发现三个螺钉的平均最大直径和最大长度存在性别差异。
结论:本研究为跟骨骨折经皮螺钉内固定提供了有效的定位。为了更安全、更高效地放置螺钉,我们建议个性化的术前三维重建模拟。需要进一步的生物力学研究来验证螺钉的功能。