后路全脊椎整块切除术治疗下腰椎恶性肿瘤的应用解剖研究

Anatomy Study on Posterior Total En Bloc Spondylectomy in Lower Lumbar Malignant Tumors

目的：为一期后路全脊椎整块切除术治疗下腰椎恶性肿瘤提供解剖学基础。方法：在12具成人尸体标本上模拟经后路下腰椎全脊椎切除手术，观测两侧L2/3、L3/4腰神经前支汇合形成的区域面积、L2和L3神经根在弓根外缘向外侧牵拉距硬膜外缘的最大距离，L3、L4椎体侧方腰大肌自椎体外侧缘向外侧可拉开的最大宽度，椎体前方大血管向前方可推开的最大距离，L4椎体下缘与两侧髂嵴顶点连线上下的关系和b、L4椎体的中矢状径、中高及中横径及最大矢状径。结果：L2/3、L3/4。腰神经前支围成的区域面积分别为（352．52±55．66）mm2、（418．65±64．26）mm2；L3、L4神经根在弓根水平向外侧牵拉后距硬膜外缘的最大距离为（26．79±2．23）ram、（27．33±3．37）mm；L3、L4椎体侧方腰大肌自椎体外侧缘向侧方可拉开的最大宽度为（37．96±1．62）mm、（38．37±2．70）mm，L3、L4椎体的最大矢状径（30．32±2．44）mm、（31．15±2．38）mm；L3、L4椎体前大血管向前可推开最大距离分别为（19．07±1．51）mm、（17．66±2．87）mm2L4椎体下缘位于两侧髂嵴顶点连线以上的有8例（66．67％），位于连线下方的有4例（33．33％）。结论：（1）通过分离腰丛神经和牵开腰大肌可以在其间获得一个安全的路径旋出前方椎体，避免了从神经根之间旋出椎体而带来的神经损伤和硬膜撕裂的风险。（2）对于L1节段和部分k节段下缘较高的病例，实施单纯后路全脊椎切除术是完全可行的。

Objective：To study anatomical knowledge of posterior total en bloc spondylectomy for the lower lumbar malignant tumors. Methods：The posterior total en bloc spondylectomy surgery was simulated for lower lumbar in 12 cadavers to study the area enclosed by the spinal nerves at L3 and L4 segments ,the distance between the dural border and corresponding L2, L3 nerves roots when they were retracted extremely to the later- al, the distance of the psoas retracted laterally at level of L3 and L4, the distance of the aorta and inferior vena cava pushed forward at L3 and L4, and the vertical height between lower edge of L4 vertebra and level of iliac crest peak, the median sagittal diameter, median height and median coronal diameter of L3 and L4 vertebra. Re- suits ： The area enclosed by the spinal nerves was （352.52 ± 55.66） mm2 at L2/3, （418.65 ± 64.26 ）mm2 at L3/4, the respective distance between the L2, L3 nerves roots retracted extremely to the lateral and the corre- sponding dural border were （26.79 ±2.23） mm and （ 27.33 ：± 3.37） mm. The width of the psoas retracted laterally was （37.96 ± 1.62） mm at L3, （ 38.37 ± 2.70） mm at L4. The lengthest sagittal diameter was （ 30.32 ± 2.44）mm at L3, （31.52 ± 2.38）mm at L4, the distance of the aorta and inferior vena cava could push for- ward was（ 19.07 ± 1.51 ） mm at L3, （ 17.66 ± 2.87 ） mm at L4. The lower edge of L4 vertebra locates above the level of iliac crest peak were in 8 cases （66.67%） , 4 cases were below the level（33.33% ）. Conclusions： （ 1 ） The area enclosed by spinal nerves is not large enough to roll out the lower lumbar whole vertebral body, rough operation can cause nerve damage and dural tear, but after lumbar plexus dissection and psoas muscle re- tracted laterally, a safe space can be acquired. （2） The posterior - only total en bloc spondylectomy surgery is likely to suit for L3 or part of L4 malignant tumors in the circumstances of the lower edge locates above the level of iliac crest peak.