Clinical anatomy study of autonomic nerve with respective to the anterior approach lumbar surgery

Introduction  Male genital dysfunction was recognized as a complication following anterior approach lumbar surgery. Disruption of efferent sympathetic pathways such as the abdominal aortic plexus (AAP) and superior hypogastric plexus (SHP) which lied pre-abdominal aorta and iliac artery had been thought as the main reason. Though there were some clinical reports of retrograde ejaculation, the applied anatomic study of the autonomic nerve anterior to the lumbar was little. The purpose was to find out a lumbar surgery approach which was ejaculation preservation through the detailed study of the anatomy and histology observation of the autonomic nerve anterior to the lumbar vertebrae. Methods  The lumbar region of ten male cadavers was dissected and analyzed. We investigated the relationship between the peritoneum and abdominal aorta, iliac artery and sacral promontory fascia, as well as the trend and distribution of the autonomic nerve and SHP anterior to the L5-S1. We also observed the distribution of autonomic nerve at retroperitoneum through hematoxylin and eosin (HE)-stained tissues pre-aorta, para-aorta, and pre-vertebrae sacrales. Results  Superior hypogastric plexus, which deviated to left, located in a triangle formed by the common iliac arteries and its bilateral branches, its truck sited anterior to the lumbarsacral space in seven cases (70%), and anterior to sacrum in three cases (30%); at the aortic bifurcation, SHP strided over left iliac artery from left-hand side, then located in front of sacrum in four cases (40%), and sifted to the left at the lumbar sacral promontory in six cases (60%); from both anatomic and histological view, the autonomic nerve plexus lying in an fascia layer of retroperitoneum. Conclusion  At the anterior approach lumbar surgery of trans-peritoneum, we should choose the right-hand side incision; the SHP should be pushed aside carefully from right to left along intervertebral disc. The accurate surgical plane was at the deeper layer of autonomical nerve fascia; we also could lift the complete autonomical nerve layer which lies behind the aorta and lumbar sacral promontory, so that the autonomic nerve could be preserved.