Akkaya Taylan, Ozturk Emine, Comert Ayhan, Ates Yesim, Gumus Haluk, Ozturk Halil, Tekdemir Ibrahim, Elhan Alaittin
Department of Anesthesia and Pain Unit, Ministry of Health Diskapi Yildirim Beyazit Research and Educational Hospital, Ankara, Turkey.
Anesth Analg. 2009 Mar;108(3):1037-41. doi: 10.1213/ane.0b013e3181966f03.
Obturator nerve block is one of the most technically challenging regional anesthesia techniques. Recently, the characteristics of the nerve have been described using ultrasound. However, clinical application of proximal ultrasound-guided obturator nerve block on patients has not been reported. In this study, we used ultrasound to describe the anatomical localization of the obturator nerve and its two branches in cadavers, volunteers, and also patients.
A hyperechoic triangular shape formed by the superior pubic ramus, posterior margin of the pectineus muscle and anterior aspect of the external obturator muscle containing the obturator vessels and nerve was defined by ultrasound imaging in cadavers. In eight volunteers, bilateral obturator nerve images were obtained and the distances to specific landmarks (femoral artery, femoral vein, and pubic tubercle) were recorded. Ultrasound-guided obturator nerve block was further performed in 15 patients by using the previously defined approach. The final distance of the needle tip to the femoral artery, distances between the needle insertion point to the pubic tubercle and the depth of needle insertion were recorded.
The rates of common obturator nerve, anterior and branching obturator nerve pattern visibility with ultrasound were determined in 12/16, 13/16, and 7/16 sites in volunteers, respectively. Mean (SD) values of critical landmarks obtained from volunteers were obturator nerve-femoral vein 12.9 +/- 2.9 mm and obturator nerve-pubic tubercle 19.9 +/- 2.6 mm. Mean measurements obtained from patients were: femoral artery- needle tip 18.5 +/- 2.4 mm, needle depth 48.3 +/- 10.4 mm, pubic tubercle- needle insertion point (horizontal) 18.8 +/- 2.0 mm, and pubic tubercle- needle insertion point (vertical) 21.1 +/- 2.9 mm. Visual analog scale scores obtained from patients at 1 and 24 h were lower compared to baseline values (P < 0.001). Ninety-three percent (14 of 15) of the patients reported satisfaction from the block.
Landmarks defined in this clinical trial can be used in patients for obturator nerve block with ultrasound guidance.
闭孔神经阻滞是技术要求最高的区域麻醉技术之一。最近，已利用超声描述了该神经的特征。然而，尚未有关于近端超声引导下闭孔神经阻滞在患者中的临床应用报道。在本研究中，我们利用超声描述了闭孔神经及其两个分支在尸体、志愿者以及患者中的解剖定位。
在尸体中通过超声成像确定由耻骨上支、耻骨肌后缘和包含闭孔血管及神经的闭孔外肌前缘形成的高回声三角形。在8名志愿者中获取双侧闭孔神经图像，并记录其与特定标志（股动脉、股静脉和耻骨结节）的距离。通过使用先前确定的方法，在15名患者中进一步实施超声引导下闭孔神经阻滞。记录针尖到股动脉的最终距离、进针点到耻骨结节的距离以及进针深度。
在志愿者中，超声显示闭孔神经主干、前支及分支型的比例分别为12/16、13/16和7/16。从志愿者获得的关键标志的平均（标准差）值为：闭孔神经-股静脉12.9±2.9毫米，闭孔神经-耻骨结节19.9±2.6毫米。从患者获得的平均测量值为：股动脉-针尖18.5±2.4毫米，进针深度48.3±10.4毫米，耻骨结节-进针点（水平）18.8±2.0毫米，耻骨结节-进针点（垂直）21.1±2.9毫米。患者在1小时和24小时时的视觉模拟评分低于基线值（P<0.001）。93%（15名中的14名）的患者对阻滞表示满意。
本临床试验中确定的标志可用于在超声引导下对患者实施闭孔神经阻滞。
