目的　为从腰神经根途径开展脊髓损伤后肢体运动功能重建的研究提供解剖依据。  方法　对10只SD大鼠灌注后进行显微解剖研究，并对30只SD大鼠进行手术中观察和测量，观察腰神经根的解剖特点。  结果　SD大鼠腰神经根共有6对，其中L2~4组成股神经支配股四头肌，L5~6组成坐骨神经支配股后肌群，腰髓约平对T12,13及L1、2水平。腰神经前根1束较细，后根2束较粗，腰神经前、后根出硬膜后，有各自独立的硬膜囊包绕后直至后根神经节处。  结论　SD大鼠腰神经根解剖特征与人类不同。

Objective　To provide anatomical basis for the functional reconstruction of the lumbar root after spinal cord injury.　Methods　Anatomical features of the lumbar roots were observed and summarized on 30 SD rats during the operation and on 10 SD rats microdissected after perfusion.　Results　There were six couples of the lumbar roots in SD rat. The L2-L4 roots mainly made up femoral nerve which dominating the quadriceps femoris. Sciatic nerve was composed of the L5-L6 roots which dominating the dorsal femoris muscle group. The lumbar medullary originated at the 12th thoracal vertebra and terminated at the 2th lumbar vertebra. The lumbar anterior root with one bunch was thin and its posterior root with two bunches was thick. Its anterior root and posterior root were wrapped together in one dura mater of spinal cord. The dura mater of spinal cord was thick and solid. The ventral and dorsal foots of spinal nerves were surrounded by meningeal tubes seperately till the point of dorsal root ganglion.　Conclusions　There are some difference in anatomical character of lumbar roots between SD rat and human.