后路骶骨次全切除的相关应用解剖

目的 测量骶骨标本及解剖骶后区，了解骶骨次全切除术相关的解剖学参数，以指导临床应用。方法 观测50个干燥的成人骶骨标本，采用求积仪计算经S1、S2骶后孔上、下缘所切除的骶髂关节面积的百分率；解剖19具防腐保存的正常成人骨盆标本，从骶后入路观察骶髂关节与各骶后孔、骶神经的毗邻关系；以髂后上棘至同侧的骶角连线（PS线）为基线，测量各神经出梨状肌上、下缘处至PS线的垂直距离。对结果进行统计分析。结果 经S1骶后孔上缘所切除的骶髂关节面均超过50％，经S1骶后孔下缘所切除的骶髂关节面大部分超过50％。而经S2骶后孔上缘所切除骶髂关节面在50％以下者，男性为32．14％，女性为22．73％；72．0％的骶髂关节下缘位于第2、3骶后孔之间，90％S2神经根从其前方经过；阴部神经主要由S3神经前支组成；阴部神经距骶骨最近。结论 经S2骶后孔上缘水平切除骶骨对骶髂关节的稳定性无明显影响；骶髂关节下缘可作为术中确定S2神经位置的骨性标志。

Applied anatomy related to partial sacrectomy through posterior approach

Objective To explore the anatomical parameters related to partial sacrectomy by sacral specimen measurement and dissection of the posterior region of sacrum, so as to provide guidance for clinical practice. Methods Fifty dry sacrum specimens were prepared for measuring proportions of sacroiliac joint surface remained after partial sacrectomy via the upper and lower edges of the first and second posterior sacral foramens. Nineteen preserved pelvic specimens of adult cadavers were dissected through the posterior approach to observe the relationship between the sacroiliac joint and the posterior sacral foramen and sacral nerves. The vertical distance from the sacral nerve emerged above and below the piriformis muscle to the PS line connecting the posterior superior iliac spine and the sacral horn line was measured. The data were statistically analyzed. Results More than half of the sacroiliac joint surface were removed in all or in majority of cases when the resection was carried out through either the upper or lower edge of first posterior sacral foramen, while less than 50 %, a mean of 32.14% in male and 22.73% in female, were removed when the resection was through the upper edge of the second posterior sacral foramen. The inferior border of the sacroiliac joint was located at the level between the second and third posterior sacral foramen in 72.0% of the specimens, and the second sacral nerve root passed in front of it in 90% specimens. The pudendal nerve consisted mainly of the third sacral nerve closeset to the sacrum. Conclusions A partial sacrectomy via the upper edge of the second posterior sacral foramen will not affect the stability of the sacroiliac joint, the inferior border of this joint can be used as an important bone marker of the second sacral nerve during the operation.