基于CT三维视图的成人正常锁骨曲度及髓腔形态学参数的影像解剖学研究

目的 探讨成人正常锁骨的曲度和髓腔形态学CT影像解剖学参数,为临床手术方案的选择和锁骨固定装置的设计提供参考。方法 纳入2021年3月—8月河北医科大学第三医院影像科行胸部螺旋CT扫描的成年国人中锁骨形态正常且完整的92例CT影像学资料,其中男44例、女48例,年龄20~87（51±17）岁,按年龄分为<60岁组（61例）和≥60岁组（31例）。应用Calculate 3D工具重建出锁骨CT三维影像模型;应用“Inertial Axes”功能建立锁骨的惯性轴及其两端坐标;应用“Reslice Objects”功能重新分割锁骨CT三维影像模型,生成调整后的锁骨三维视图,并基于此观察锁骨的一般形态。依据惯性轴长度将锁骨八等分后,可得到7个等距的矢状面髓腔截面,自锁骨远端向近端依次命名为S1~S7。使用“Measure”工具,在冠状位及水平位视图上分别测量和计算锁骨体积、表面积、长度、内外两侧曲率半径和深度、远近两端关节面宽度和高度;在矢状位视图上分别测量7个截面的皮质厚度、髓腔面积、最长径和最短径。采用独立样本t检验或方差分析对各指标测量结果进行不同性别、年龄和截面间的比较。结果 本组92例92侧正常成人锁骨CT测量结果显示,锁骨体积（29 518.4±7 049.2） mm³,表面积（8 271.8±1 291.2） mm²,长度（143.7±11.5）mm,内侧曲率半径为（128.3±28.0） mm、深度为（16.4±2.6） mm,外侧曲率半径为（56.7±19.4） mm、深度为（11.4±2.6）mm,近端关节面的宽度为（20.5±3.8）mm、高度为（21.8±3.4）mm,远端关节面的宽度为（15.4±3.5） mm、高度（12.8±2.3） mm。锁骨皮质厚度从S2向两端递减,其中S2皮质最厚（3.5±1.1） mm],S7皮质最薄（2.6±0.7） mm]。髓腔面积、最长径和最短径在S4处最小并向两侧扩大,其中S4髓腔面积为（24.7±11.0）mm²、最长径为（6.7±1.7） mm、最短径为（4.6±1.2） mm。7个截面间各指标差异均有统计学意义（P值均<0.05）。以上各指标中：近端关节面宽度和外侧曲率半径测量值不同性别间比较差异均无统计学意义（P值均>0.05）,其他指标测量值男性均大于女性,差异均有统计学意义（P值均<0.05）;与<60岁组相比,≥60岁组锁骨远端关节面的宽度和高度,以及各截面的髓腔面积、最长径和最短径较大,而皮质较薄,差异均具有统计学意义（P值均<0.05）。结论 在不同截面处,锁骨的皮质厚度及髓腔面积、最长径和最短径等指标存在较大差异;在选择手术方式时,术者需要考虑性别差异、年龄差异,以及骨折部位和类型的影响。

Imaging anatomic study of tortuosity and morphological parameters of medullary cavity of adult normal clavicle based on CT three-dimensional view

Objective This study aims to observe and measure clavicle anatomical parameters related to the general morphology, tortuosity, cortical thickness, and medullary cavity morphology, explore the general pattern of morphological changes in the Chinese clavicle, and provide reference for the selection of the optimal surgical treatment options and the design of clavicle fixation devices. Methods The imaging data of normal and intact clavicles of adult patients aged 20-87 (51±17) years who underwent chest CT scans at the Imaging Department of the 3rd Hospital of Hebei Medical University from March to August 2021 were analyzed. The samples were divided into groups of male (n=44) and female (n=48) or groups of aged <60 years (n=61) and aged ≥60 years (n=31). The "Reslice Objects" function of Mimics software was used to re-segment the clavicle model according to the inertia axis to obtain the adjusted three-dimensional view and measured the following clavicle indicators: volume, surface area, length, curvature radius, and depth of the both sides; width and height of the articular surfaces at both ends; and average cortical thickness, area, longest diameter, and shortest diameter of medullary cavity of seven isometric sagittal sections (named S1 -S7 from the distal end to the proximal end of clavicle after dividing the clavicle equally according to the length of the inertia axis. Results were compared among the groups of gender, age, and across-sections by Student's t-test or analysis of variance. Results The following data were obtained: volume (29 518.4±7 049.2) mm³, surface area (8 271.8±1 291.2) mm², length (143.7±11.5) mm, medial radius of curvature (128.3±28.0) mm and depth (16.4±2.6) mm, lateral radius of curvature (56.7±19.4) mm and depth (11.4±2.6) mm, width of proximal articular surface (20.5±3.8) mm and height (21.8±3.4) mm, and width of distal articular surface (15.4±3.5) mm and height (12.8±2.3) mm. The thickness of the clavicular cortex decreased from S2 to both ends. The thickest (3.5±1.1) mm cortex was found in S2, and the thinnest (2.6±0.7) mm in S7. The area and the longest and shortest diameter of the medullary cavity were smallest at S4 and enlarged bilaterally, where the medullary cavity at S4 had an area of (24.7±11.0) mm², with the longest diameter of (6.7±1.7) mm and the shortest diameter of (4.6±1.2) mm. Significant differences were found in all indices among the seven sections (all P values <0.001). Significant differences were also detected in all indicators except for the width of the proximal articular surface and the radius of lateral curvature between male and female groups (all P values <0.05). In individuals aged ≥60 years, the width and height of the distal articular surface as well as the area and the longest and shortest diameter of medullary canal at different cross-sections were larger, and the cortex was thinner. Conclusion The cortical thickness, medullary cavity area, and longest and shortest diameter of clavicle were significantly different among different sections. When choosing the operation method, the operator needs to consider the influence of differences in gender, age, and fracture location and type.