腕舟骨运动轨迹的数字化三维模拟分析

Three-dimensional digital analysis of the trajectory of scaphoid bone

背景:腕关节的舟骨骨折在腕部骨折中非常常见,但是由于腕舟骨骨折不愈合率极高,通过研究其在体运动轨迹为其固定提供最佳位置的固定方式是具有极其重要的意义。目的:探讨正常腕舟骨运动轨迹,为体内研究三维运动学分析提供一种方法。方法:纳入20名健康成人志愿者(男女各10名),均行右腕关节连续螺旋CT扫描,右手腕分别于中立位,掌屈、背伸各15°,30°,45°,60°位,桡偏10°,20°、尺偏15°,30°位进行扫描,将原始DICOM数据导入Materialise Mimics Innovation Suite 15.0软件,通过三维建模,重建桡骨远端及舟骨,并行骨块三维配准,分别测定各骨块质心,重建舟骨的运动轨迹,计算骨块间的距离。结果与结论:腕关节屈曲及背伸或尺偏及桡偏运动时,舟骨质心相对于桡骨远端质心之间的距离是不同的,腕关节背伸60°,尺偏30°位舟骨质心相对于桡骨距离最大;背伸30°,桡偏20°,则距离最小。各位置桡骨远端质心与舟骨质心间距离男女间比较有统计学差异。实验精确测定腕舟骨的质心,为重建舟骨的运动轨迹提供了新的科学方法。

BACKGROUND:Scaphoid fracture is commonly seen in wrist fracture,but its nonunion rate is high.Therefore,studying trajectory of normal scaphoid bone is of great significance for selecting optimal fixation way and position.OBJECTIVE:To study the trajectory of normal scaphoid bone,and to provide method for three-dimensional kinematics analysis.METHODS:Twenty normal adults(n=10 in either sexes)were enrolled,and the right wrist underwent spiral CT scan in neutral,palmar flexion,dorsiflexion at 15,30,45 and 60 degrees,radial deviation at 10 and 20 degrees and ulnar deviation at 15 and 30 degrees,respectively.The original DICOM data were imported into Materialise Mimics Innovation Suite 15.0 to reconstruct distal radius and scaphoideum,and three-dimensional registration.The centroid of each bone was measured,and trajectory of scaphoideum was reconstructed to calculate the displacement value.RESULTS AND CONCLUSION:In palmar flexion and dorsiflexion or radial/ulnar deviation,the distance between centroid of scaphoideum and distal radius was different.In the 60 degrees of dorsiflexion and 30 degrees of ulnar deviation,the displacement was largest.In the 30 degrees of dorsiflexion and 20 degrees of radial deviation,the displacement was smallest.The displacement value in different positions showed significant differences between sexes.In summary,the accurate determination of the centroid of scaphoid bone provides a new scientific method for the reconstruction of scaphoid movement.