目的　研究前臂骨间背侧神经及其肌支的解剖学特征，为体表定位提供形态学基础。   方法　解剖 30具成人防腐尸体的60侧上肢骨间背侧神经及其肌支，观察骨间背侧神经的行程与神经分叉点，测量分叉点分别至肱骨外上髁（LHE）、桡骨Lister结节（LTR）、尺骨茎突（SPU）的距离等参数，通过三圆交汇法及神经分段法来确定神经的体表位置。  结果　骨间背侧神经在发出指伸肌支、小指伸肌支及尺侧腕伸肌支后，主干有4个主要分叉点（O、O1、 O2、 O3）；以分叉点分别至LHE 、LTR 、SPU 的平均距离为半径，LHE 、LTR 、SPU为圆心，绘制3个圆，三圆交汇的点或区域可作为神经的体表定位；4个分叉点又可将骨间背侧神经分为7段（O点上段、OO1段、O1点下段、OO2段、O2点下段、O2O3段、O3点下段）。   结论　骨间背侧神经分叉点结合三圆交汇定位及神经分段法，根据神经损伤的临床表现，可明确神经损伤的位置。

Objective　To study the anatomic features of dorsal interosseous nerve and its muscular branches and to provide morphological basis for positioning surface positioning.　Methods　60 dorsal interosseous nerves and its muscular branches from 30  embalmed arm specimens of adult cadavers were dissected. The courses and the bifurcation points of dorsal interosseous nerve were explored. The distances from each bifurcation point respectively to the latera humeral epicondyle(LHE), the Lister's tubercle of the radius (LTR) and the styloid process of ulna (SPU) were measured. The surface position of dorsal interosseous nerve was determined by the “three circle intersection localization method” and “nerve segmentation method”.   Results  There were 4 main bifurcation points of the nerve trunk after dorsal interosseous nerve sent out extensor digitorum branch, extensor digiti minimi branch， and extensor carpi ulnaris branch. The 4 bifurcation points were named O,O1,O2 and O3. Three points, i.e, LHE, LTR and SPT were taken as the center of a circle，and the distance from the bifurcation point to the three points as the radius to draw three circles. The intersection points or regions can be used as the surface location of the nerve. Dorsal interosseous nerve was divided into 7 segments, which were segment above O, segment between O and O1, segment below O1, segment between O and O2, segment below O2, segment between O2 and O3, and segment below O3.    Conclusion    According to the clinical manifestation of dorsal interosseous nerve injury and bifurcation point combined with “three circle intersection localization method” and “nerve segmentation method”, the location of nerve injury could be identified.