目的　探讨经下颈椎侧方臂丛后解剖间隙进行椎间孔镜手术的可行性。  方法　40侧成人尸体标本，沿胸锁乳突肌后缘对应C3~7椎体作纵切口，由浅入深经臂丛前、后方按临床手术显露椎间孔途径逐层解剖观测至椎体及附件结构，并模拟手术，牵拉相应组织，测量其牵拉角度、范围。  结果　①臂丛C5~8根长度、根角度及根间距测量结果表明臂丛前、后入路均可直视神经根对椎间孔周围病变进行操作；② C4~6横突与膈神经的距离测量结果表明与臂丛前入路相比，臂丛后入路不易伤及膈神经；③C3~7横突与颈交感干的距离测量结果表明与臂丛前入路相比，臂丛后入路不易伤及颈交感干；④胸导管70%在C7~T1水平汇入静脉角，C7水平臂丛前入路要注意保护胸导管，臂丛后入路不易损伤胸导管；⑤在C7横突水平处将椎动脉向外牵拉的距离为(2.5±0.4)cm，臂丛前、后入路均应注意保护椎动脉；⑥C7横突末端下方至胸膜顶的距离为(1.9±0.4)cm，C7水平臂丛前、后入路均可能伤及胸膜顶。  结论　下颈椎侧方臂丛后解剖间隙可为颈椎间孔镜手术提供安全的手术入路。

Objective　To evaluate the feasibility of lower cervical transforaminal endoscopic surgery by lateral approach.　Methods　Applied anatomy in 40 sides of 20 adult cadavers were performed. Vertical incision at C3~7 levels along posterior margin of stenomastoid was performed through anterior or posterior space of brachial plexus (ASBP or PSBP) for lateral approach to target vertebra. Subsequently, dissection and anatomic measurement of important structures were carried out in mimic surgery.　Results　 (1) According to the lengths, root angles and root intervals of C5 to C8 nerve roots, sufficient exposure of these nerve roots was proved in transforaminal endoscopic surgery via anterior or posterior space of brachial plexus. (2) According to the distances between phrenic nerve (PN) and anterior tubercles of transverse processes (ATTP) of C4 to C6 vertebrae, PN was invulnerable in surgery through PSBP. (3) According to the distances between cervical sympathetic trunk (ST) and ATTPs of C3 to C7 vertebrae, lower risk in cervical ST injury was revealed in surgery via PSBP than that via ASBP.  (4) Thoracic duct (TD) ran into venous angle between C7 and T1 vertebra levels in 70% cases, and lower risk in TD injury was revealed in surgery via PSBP than that via ASBP. (5) Vertebral artery (VA) was distracted laterally by (2.5±0.4)cm at C7 vertebral level in mimic surgeries. Thus VA protection should be concerned in surgery both via ASBP and PSBP. (6) The distance between cervical pleura and C7 vertebral transverse process tip was (1.9±0.4)cm. Cervical pleura injury was observed in surgery via ASBP or PSBP.　Conclusions　Safe lateral approach through PSBP is proved for lower cervical transforaminal endoscopic surgery.