腰骶部选择性脊神经后根切断术术中脊神经后根节段定位的应用解剖

Applied anatomy of indentication of segments of dorsal roots in spinal posterior roots rhizotomy

目的为临床选择性脊神经后根切断术提供可靠的后根形态学鉴别依据。方法：在２０例成人防腐灌红色乳胶的腰骶部脊柱标本上，对Ｌ１～Ｓ２的后根进行巨－微解剖学观测。结果各节段后根在马尾近端呈冠状位的内外平排，从内向外依次为Ｓ２～Ｌ１的后根；马尾远端，低节段后根位于后内；高节段后根位于前外侧。Ｌ１～Ｓ１后根的直径逐渐增加，以Ｓ１后根最粗大。各节段后根进脊髓处，Ｌ５和Ｓ１后根之间有明显分界线，相邻节段后根之间，有恒定小静脉分隔。以终丝起点为定点，各节段后根与终丝的距离和成角从Ｓ２到Ｌ１逐渐增加。结论腰骶部选择性脊神经后根切断术术中后根节段的定位在多椎板切除暴露时，可根据椎间孔的节段序数定位后根的节段；在限制性椎板切除的选择性脊神经后根切断术术中，依靠后根出脊髓处，Ｌ５和Ｓ１之间有明显分界、相邻节段后根间有恒定小静脉来定性鉴别，也可根据终丝起点水平，各节段后根与终丝的距离和成角来鉴别后根节段。

Objective To provided morphologic bases for how to indentify the segment of dorsal roots during spinal posterior roots rhizotomy (SPR) Method The posterior construction of T 10 ～S 4 segments was removed in 20 antiseptic lumbosacral spines specimens perfused with red emulsion The posterior roots of L 1～S 2 segments was observed and measured after the conus medullaris and cauda equia were exposured Result All dorsal roots ranged from medial to lateral parallelly on the cornal section in the proximal cauda equia The S 3～5 segments dorsal roots formed a big bundle at each side of the filum terminale The S 2～L 1 segments dorsal roots ran from medial to lateral, and the high segments were located at posterior medial and the low segments were located anterior-lateral at the distal part of the cauda equia The diametre of dorsal root was increased gradually from L 1 to S 1, and the S 1 was the biggest one There was a bundary line between L 5 and S 1 dorsal roots and a permanent vein were found between two adjacent dorsal roots at the point of dorsal roots going into the spinal cord The distance and angle between the dorsal roots and filum terminale were gradually increased from S 2 to L 2 at the starting point The distance and angle between the dorsal roots and filum terminale were gradually increased from S 2 to L 1 at the starting point of filum terminale Conclusion The segment of the posterior roots could be identified in lumbosacral mulitiple laminectomy of SPR according to intervertebral foramen, in limited laminectomy of SPR, the segment of the posterior roots were indentified by the bundary line between L 5 and S 1 dorsal roots and a permanent vein between the two adjacent segments or the distance and angle between the dorsal roots and filum terminale at the starting point of filum terminale