男性尿道膜部括约肌支配神经的应用解剖

Applied anatomy of nerves innervating male urethra membrane sphincter

目的:为根治性膀胱前列腺切除手术中保护尿道控尿神经提供解剖学依据。方法:对15例成年男性尸体盆腔标本进行解剖,观察支配尿道膜部括约肌神经的组成、形态及毗邻关系。结果:尿道膜部括约肌接受下腹下丛和阴部神经盆内盆外分支支配,其中盆神经起源于下腹下丛远端盆内脏神经分支,沿肛提肌表面到达尿道膜部5点和7点位;40%的标本中阴部神经存在盆内分支,此分支自阴部管内的阴部神经主干穿肛提肌进入盆内,与盆神经一起支配尿道膜部括约肌,其进入尿道膜部的位置距离前列腺尖部(5.3±1.8)mm。在53.3%的标本中阴茎背神经发出分支到达尿道膜部,此分支进入尿道膜部的位置距离前列腺尖部(4.2±1.1)mm。结论:根治性膀胱前列腺切除术中对控尿神经的保护是多方面的,术中对精囊和前列腺尖部的操作最易损伤控尿神经。

Objective： To provide anatomical evidences for preserving continence nerves in radical cystectomy and prostatectomy. Methods： Cadaveric dissections of 15 male specimens were undertaken to investigate nerves innervating urethra membrane sphincter, Results： Membrane sphincters were innervated by branches of inferior hypogastric plexus,intrapelvic and extrapelvic branches of pudendal nerve.The pelvic nerve from inferior hypogastric plexus originated from the caudalmost root of the pelvic splanchnic nerve,running along the surface of the levator ani to enter the urethra membrane at the 5 and 7 o＇clock positions.In 40% of specimens we found out intrapelvic branches which were given by pudendal nerve.Before leaving the Pudendal canal,pudendal nerve gave an intmpelvic branch that traversed the levator ani to course with the pelvic nerve to innervate the membrane sphincter,the distance between these intrapelvic branches and prostatic apex was （5.3 ± 1.8）mm.The branches originating from the dorsal nerve of penis innervated urethra membrane in 53.3% of specimens, and these nerve branches were located （4.2 ±1.1 ）ram from the prostatic apex. Concluaions： Preservation of continence nerves during radical cystectomy and prostectomy are all around and dissections of seminal vesicle and the prostatic apex are most likely to injure the continence nerves.