桡骨髓腔的形态与蛇形髓内针设计关系

Relationship between the shape of radial medullary cavity and the design of snakelike intramedullary needle

目的:为设计桡骨髓腔内固定器材提供解剖学基础。方法:成人桡骨30例,按20等份横断,观察髓腔形态,测量前后径和横径。结果:总体形态,桡骨髓腔上端横截面呈圆形或矢状位椭圆形,上端最大处为3/20处,前后径平均9.1mm,横径8.5mm。骨干和下端呈前后扁平状,其横截面近似椭圆形,其最小处为桡骨中份,前后径平均4.4mm,横径5.9mm。最大处为下端17/20或18/20处,前后径平均8.0mm,横径13.3mm。结论:桡骨髓腔中间小,两端大;上端呈圆形或椭圆形,骨干和下端呈扁圆形。其形态特点适合用弹性蛇形髓内针固定器械。

Objective: To provide anatomic basis for the design of the internal fixation equipment in radial medullary cavity. Methods: Thirty adult radii were used in this research. Each of them was divided into 20 equal portions and transversally sawed into 20 cross sections. The shape, anteroposterior and transverse diameters of medullary cavity of each section were observed and measured. Results: The cross section of the medullary cavity of upper radius appeared round shape and at its sagittal position appeared oval shape. The largest area was located in 3/20 cross section and its anteroposterior and transverse diameters were 9.1 mm and 8.5 mm respectively. The anteroposterior shape of shaft and lower end of the radius was flat. The cross section of lower radial medullary cavity was oval and the smallest area of them located in the middle portion of the radius and its anteroposterior and transverse diameters were 4.4 mm and 5.9 mm respectively. The largest area in lower extremity of the radius located in the 17/20 or 18/20 cross section. Its anteroposterior and transverse diameters were 8.0 mm and 13.3 mm respectively.Conclusions: The medullary cavity of the radius is small in the middle portion and large in the upper and lower ends. The cross section in the upper end is round or oval, while that of shaft and lower end is flat. Therefore, the shape in medullary cavity of the radius is suitable for the application of the elastic snakelike intramedullary needle.