锁骨钩钢板对肩关节三维瞬时运动影响的FSA分析
FSA analysis of the effects of clavicular hook plate on the three-dimensional instantaneous motion of shoulder joints

目的·探讨锁骨钩钢板对锁骨骨折术后肩关节三维瞬时运动的影响。方法·选取采用锁骨钩钢板固定术治疗的锁骨骨折患者。采用平板型荧光镜透视系统结合螺旋CT检查技术，通过薄层CT建立锁骨和钢板的三维重建模型，根据锁骨的解剖标记点建立局部坐标系，并与锁骨钩钢板一同匹配到荧光镜透视系统捕捉的不同体位的锁骨X线透视图像上，在计算机上模拟生理载荷下锁骨钩钢板和锁骨共同作用的三维运动状态。根据在锁骨和钢板上建立的三维坐标系，测量在不同体位变化时，锁骨和锁骨钩钢板在3个坐标轴方向的位移和旋转数值。分析在骨折愈合后，锁骨钩钢板对肩关节运动的影响。结果·锁骨钩钢板对患者的肩关节外展内收和内外旋活动均有影响。本研究中患者的锁骨和锁骨钩钢板在内外旋变化中同正常人的锁骨旋转角度（27°）几乎无差异，锁骨远端在向前的位移（均值6.8 mm）同正常人（5.1 mm）比较有增大趋势，并且患者平均外展角度只能达到84.79°。结论·带有锁骨钩钢板的患者，在骨折临床愈合后且未实行全肩关节活动前，即术后3～6个月，应及时取出内固定，防止形成肩峰撞击。
： Objective · To explore the effects of clavicular hook plate on the three-dimensional instantaneous motion of shoulder joints after clavicular fracture operation. Methods · Three patients with clavicle fracture who underwent clavicular hook plate fixation were enrolled. A flat type fluoroscopic imaging system and spiral CT were used and a 3D reconstruction model of the clavicle and hook plate was built via thin layer CT. The local coordinate system was established according to anatomical landmarks of the clavicle. The clavicular hook plate and the local coordinate system were matched on X ray images of the clavicle at different postures captured by the fluoroscopic imaging system. The 3D motion resulted from the interaction of the clavicular hook plate and the clavicle under physiological load was simulated by the computer. The displacement and rotation values of the clavicular hook plate and the clavicle at three axis directions were measured for different postures according to the 3D coordinate system established based on the plate and the clavicle. The effects of clavicular hook plate on the motion of shoulder joints after fracture healing were analyzed. Results · The clavicular hook plate affected both abduction, intorsion and extorsion of shoulder joints. In this study, the clavicular hook plate and the clavicle had a rotation angle similar to the rotation angle of the clavicle in normal people (27°) and a larger forward displacement (average 6.8 mm) of distal clavicle as compared with normal people (5.1 mm). The average abduction angle in patients was 84.79°. Conclusion · Patients with the clavicular hook plate should remove the internal fixation timely 3-6 months after surgery in order to avoid the subacromial impingement syndrome