舟骨螺旋CT影像最长轴的确立与测量

Establishment and measurement of the scaphoid maximum length on spiral CT

目的探讨舟骨螺旋CT影像的最大长度、近端尺侧关节面与最长轴的夹角,以及二者的性别、侧别差异。方法收集30例60侧正常舟骨的螺旋CT数据,利用软件VxWork计算舟骨的最大长度、最长轴的端点位置、近端尺侧关节面与最长轴的夹角α,并检验上述数据有无性别、侧别及观察者内的差异。结果30例60侧舟骨的最大长度均值是(28.05±2.12)mm,男(29.31±1.55)mm,女(26.6±1.83)mm;男性长于女性,但侧别之间无统计学差异。∠α的均值是(23.81±2.45)°,男(23.25±2.40)°,女(24.86±2.50)°;性别、侧别之间均无统计学差异,也无显著的观察者内差异。舟骨最长轴的端点分别在舟骨远、近端的皮质上,位置较恒定;远端位于舟骨结节区的中央,近端在舟骨近端关节面背缘中1/3处;左右两侧对称。结论舟骨螺旋CT影像最大长度、近端尺侧关节面与最长轴的夹角较恒定,且无侧别差异;以健侧舟骨影像数据为依据,用以判断患侧舟骨形变是可行的。

Objective To measure the maximum length of scaphoid and the angle between the long axis and the proximal ulnar facet of scaphoid based on spiral CT scan, and also to investigate the difference of the angle and the length between the two sides as well as the two genders. Methods 30 cases of 3D CT reconstructions of bilateral normal scaphoids in a computerized operation planning and simulation system （Vxwork software） were obtained. The scaphoid maximum length, its proximal and distal points, and the angle （α） between the long axis and the proximal ulnar facet were obtained by software in this system. The differences of all the data obtained above between the two sides as well as the genders were evaluated. Results Average maximum length of 30 bilateral scaphoids generally was （28.05±2.12） mm. Scaphoid in male （29.31±1.55） mm was longer than it in female （26.6±1.83） mm , and there was no significant difference between the left and right scaphoids of the matched pairs. ∠α was （23.81±2.45）° in general, （23.25±2.40）° in male, （24.86±2.50）° in female. No difference was noted between the two sides and the genders. The position of the long axis was relatively stable, and the point on the distal pole was located in the central region of the tubercle and the point on the proximal pole was located in the middle 1/3 in the dorsal rim of the scaphoid proximal ulnar facet. The positions were symmetrical between the two sides. Conclusions The maximum length of scaphoid and the angle between the long axis and the proximal ulnar facet of scaphoid on spiral CT scan are relatively constant, and also there is no difference between the two sides, which showed normal contralateral scaphoid provided the best template for corrective surgery.