目的　为新型肱骨内固定器的设计和应用提供解剖学依据。  方法　解剖20具40侧成人上肢标本，观察腋神经、桡神经的走形及测量与相关骨性标志的距离，同时选取成人干燥肱骨标本30根，测量肱骨上段相关直径及周长，计算相关的最佳弧度。  结果　肱骨最大长（30.21±0.22）cm；大结节至腋神经距离（5.48±0.09）cm；大结节至三角肌粗隆距离（12.80±0.13）cm； 肱骨最近端至肱骨肌管入口及出口分别为（16.10±0.27）cm、（21.04±0.26）cm；肱骨上段最佳弧度（3.90±0.03）rad。  结论　新型肱骨内固定物当其弧段部的弧度达到3.9rad时，能达到很好的服帖，且有效地避免桡神经损伤的发生率。

Objective　 To provide anatomical basis for the design of a new internal humerus fixator and its application.　Methods　40 sides of adult upper limb specimens with were dissected, the course of the axillary nerve, radial nerve was observed and the distance from them to the related osseous landmarks were measured. Meanwhile, 30 adult dry humerus specimens were selected, the related diameter and circumference of the upper humerus were measured and the optimal radian was calculated.　Results　The maximum length of the humerus was (30.21±0.22) cm; The greater tubercle to the axillary nerve length was (5.48±0.09) cm; The greater tubercle to deltoid tuberosity length was (12.80±0.13) cm; The nearest end of humerus to the entry and exit of humerus muscle tube were (16.10±0.27) cm and (21.04±0.26) cm, respectively; The best radian of upper humerus was (3.90±0.03) rad.　Conclusion　When the radian of arched segment reach 3.9 rad, the new humerus internal fixation can achieve very good adherence as well as reducing the incidence of the radial nerve injury effectively.