微创腰椎前路腹膜外入路的解剖学研究与临床应用

Anatomy study and clinical application of minimally invasive anterior lumbar retroperitoneal approach

目的通过解剖学和临床研究,探讨微创腰椎前路腹膜外入路的理想显露方法。方法尸体解剖:成人防腐尸体标本21具,行左侧腹直肌旁纵切口掀开三层腹肌,观察腹膜外间隙和腹膜特点,经腹膜外入路显露L_(2)~S_(1)节段椎间盘,观察大血管与椎间盘的位置关系。影像学测量:收集100例成人腹部CT扫描,在L_(2)~S_(1)节段的腹前壁测量腹膜外脂肪与腹直肌外缘和腹壁中线的距离。收集150例成人腰椎MR检查,在L_(2)~S_(1)节段测量大血管与椎间盘前中线的距离。临床应用:采用微创前路腹膜外入路行腰椎融合术56例,男25例,女31例;年龄29~71岁,平均46.3岁。L_(2)~L_(4)采用左侧腹直肌旁斜切口,L_(4)~S_(1)行正中偏左横切口,长约8 cm,腹膜外入路充分显露椎间盘,切除椎间盘减压后行椎体间融合术,评估手术入路相关并发症。结果尸体解剖:L_(2)~L_(4)节段在弓状线近侧,腹直肌后鞘与腹膜粘连,分离时易破裂,自腹直肌鞘外缘向外腹膜逐渐变厚并出现腹膜外脂肪。L_(4)~S_(1)可经弓状线远侧显露,腹直肌后侧即为腹膜外脂肪,L_(4,5)需切开弓状线在外侧腹壁延展部,腰大肌内侧有多支髂腰静脉。L_(5)S_(1)在血管分叉远侧的右髂总动脉和左髂总静脉之间显露,骶正中血管细小或缺如,交感神经丛偏左侧。影像学测量:腹膜外脂肪在L_(2,3)、L_(3,4)、L_(4,5)节段分别距腹直肌外缘(36.2±9.9)mm、(35.2±11.6)mm、(27.6±11.2)mm,在L_(5)S_(1)节段覆盖腹直肌后侧达中线。腹主动脉左缘在L_(2,3)、L_(3,4)、L_(4,5)节段分别距中线(14.9±5.1)mm、(13.9±4.6)mm、(19.7±5.9)mm;下腔静脉在L_(2,3)、L_(3,4)节段位于中线右侧,在L_(4)~5节段跨过中线(4.6±8.7)mm;在L_(5)S_(1)节段右髂总动脉和左侧髂总静脉内缘分别距中线(14.6±6.8)mm、(17.6±5.3)mm。临床应用:56例均采用微创前路腹膜外入路顺利充分显露,手术时间70~120 min,平均90 min;术中出血15~70 ml,平均30 ml;1例L_(4,5)牵拉髂血管时髂腰静脉撕裂,双极电凝止血,均未发生神经或大血管损伤等严重并发症。结论微创腰椎前路腹膜外入路创伤小、显露充分,具有较好的可行性,L_(2~4)可采用仰卧位左侧腹直肌旁斜切口,L_(4)~S_(1)可采用法式体位正中偏左横切口。

Objective To explore the ideal method of minimally invasive anterior lumbar extraperitoneal approach.Methods Twenty-one adult embalmed cadavers underwent longitudinal incision near the left rectus abdominis,the extraperitoneal space and peritoneal characteristics were observed;the L_(2)-S_(1) disc was exposed through extraperitoneal approach,and the relationship between the anterior large vessels and the disc was observed.One hundred adult abdominal CT were collected to measure the distance between the extraperitoneal fat of anterior abdominal wall and the rectus abdominis and the anterior midline at L_(2)-S_(1) segment.One hundred and fifty adult lumbar MRI were collected to measure the distance between the anterior great vessels and the anterior midline of the intervertebral disc.Fifty-six cases of lumbar fusion were performed by minimally invasive anterior lumbar extraperitoneal approach,including 25 males and 31 females,aged 29-71 years.L_(2)-L_(4) in 8 cases was performed by left rectus abdominis oblique incision,and L_(4)-S_(1) in 48 cases was performed by median left transverse incision,with a length of about 8 cm,the complications related to the surgical approach were evaluated.Results L_(2)-L_(4) was proximal to the arcuate line,the posterior sheath of rectus abdominis adhered to the peritoneum,which was easy to rupture when separated;the peritoneum gradually thickened from the outer edge of the sheath of rectus abdominis and extraperitoneal fat appears.L_(4)-S_(1) could be exposed distal to the arcuate line,the posterior side of rectus abdominis was extraperitoneal fat,the extension of arcuate line to the lateral abdominal wall would be slightly separated proximally,and there were multiple iliopsoas veins in the medial side of psoas major muscle.L_(5)S_(1) was between the right common iliac artery and the left common iliac vein far,the median sacral vessel was small or absent,and the sympathetic nerve was to the left.Extraperitoneal fat appeared 36.2±9.9 mm,35.2±11.6 mm and 27.6±11.2 mm away from the outer edge of rectus abdominis at L_(2,3),L_(3,4) and L_(4,5) segments respectively,and covered the posterior side of rectus abdominis and reached the midline at L_(5)S_(1) segment.The left edge of abdominal aorta was 14.9±5.1 mm,13.9±4.6 mm and 19.7±5.9 mm away from the midline at L_(2,3),L_(3,4) and L_(4,5) level respectively;the inferior vena cava was located on the right side of the midline at L_(2,3) and L_(3,4) level,crossed the midline 4.6±8.7 mm at L_(4,5) level.At L_(5)S_(1) level,the left common iliac vein and the right common iliac artery were 14.6±6.8 mm and 17.6±5.3 mm away from the midline respectively.Seventy-six patients were successfully and fully exposed by small incision through extraperitoneal approach.1 case of L_(4,5) had iliac lumbar vein tear and hemostasis with bipolar electrocoagulation.The operation time was 70-120 min,with an average of 90 min;Intraoperative bleeding was 15-70 ml,with an average of 30 ml.No severe complication such as nerve and great vessel injury occurred.Conclusion Minimally invasive lumbar anterior retroperitoneal approach has small trauma and sufficient exposure with good feasibility.L_(2)-L_(4) can be exposed with supine position and oblique incision next to the left rectus abdominis muscle,and L_(4)~S_(1) with French position and median left transverse incision.