腋入法超声引导联合外周神经刺激器定位臂丛神经的解剖及其临床意义

Anatomy of brachial plexus in axilla located by ultrasound-guidance combined peripheral nerve stimulator and its clinical significance

目的:以超声引导和神经刺激器定位技术观察记录腋入路臂丛神经阻滞时以腋动脉为中心4支主要神经的解剖位置及变异,为上肢局部麻醉提供解剖学基础。方法:选择北京积水潭医院手外科2007年12月—2009年3月行腋入路臂丛神经阻滞患者167例,将超声探头垂直于胸大肌和肱二头肌交界部位放置,采集横断面图像,明确各组织结构位置及形态;使用神经刺激器分别定位记录尺神经、桡神经、正中神经和肌皮神经在以腋动脉为中心划分的4个象限内的位置;记录腋动脉距皮深度及周围腋静脉数量。结果:正中神经、尺神经和桡神经均靠近腋动脉,在腋鞘内按顺时针方向分布在神经血管束中。正中神经(83.8%)主要分布在第Ⅳ象限(腋动脉的前外侧),尺神经(72.5%)主要分布在第Ⅰ象限(腋动脉的前内侧),桡神经(61.7%)主要分布在第Ⅱ象限(腋动脉的后内侧),且3支神经间相对位置固定。肌皮神经大部分分布在喙肱肌和肱二头肌之间(89.2%),有10例(6%)肌皮神经位于腋鞘内,在腋动脉的头侧。有8例患者在腋窝处未找到肌皮神经。4支神经距离皮肤表面的距离由深到浅依次为肌皮神经(1.58±0.59)cm、桡神经(1.33±0.69)cm、正中神经(0.62±0.13)和尺神经(0.59±0.22)cm,正中神经和尺神经间深度比较差异无统计学意义(P>0.05),其余任意2支神经深度比较差异均有统计学意义(P<0.05)。167例患者中,47.3%腋鞘内静脉为2条,平均为(2.4±0.8)条。结论:在腋窝顶点处,正中神经、尺神经和桡神经围绕腋动脉按顺时针排列分布,其相对于腋动脉位置存在高度解剖变异。肌皮神经在腋鞘内外均有分布,腋动脉周围有多条静脉伴行。

Objective To perform an anatomic examination to describe the locations and variations of 4main nerves around the axillary artery using ultrasound guidance and electrical stimulation,and to provide a basement for the upper limb nerve block.Methods 167 patients undergoing axillary brachial plexus block from December 2007 to March 2009 in Department of Hand Surgery of Beijing Jishuitan Hospital were selected.The probe was placed at the intersection between pectoralis major muscle and biceps muscle.The axillary artery,the ulnar,radial,median,and musculocutaneous nerves were identified.The location of each nerve in the neurovascular bundle was recorded by subdividing the bundle into four-chart sectors with the artery in the center.Results The median,ulnar,and radial nerves proceed clockwise around the axillary artery in the neurovascular bundle.At this level,the median nerve could be found most often（83.8%）in quadrantⅣ（both anterior and lateral to the axillary artery）.The most common position（72.5%）of the ulnar nerve was found in quadrantⅠ（anterior medial to the axillary artery）,the radial nerve could be found most often（61.7%）in quadrant Ⅱ（medial posterior to the axillary artery）.In most patients（89.2%）,the musculocutaneous nerve was lined in a fascial plane between the coracobrachialis muscle and the biceps muscle,but there were a few patients showed a musculocutaneous nerve variation which lied in the neurovascular bundle,lateral to the axillary artery.There were still 8cases which musculocutaneous nerves were not found in the axilla.The distances from skin surface to the center of musculocutaneous,radial,median and ulnar nerves were（1.58±0.59）cm,（1.33±0.69）cm,（0.62 ±0.13）cm and（0.59±0.22）cm,respectively;there was no difference in the depth between median and ulnar nerves（P〉0.05）,but there were significant differences in the depth between any other two nerves（P〈0.05）.There were two veins in axillary sheat in 47.3% persons of all 167 patients,the average was（2.4±0.8）.Conclusion The median,ulnar,and radial nerves proceed clockwise around the axillary artery in the neurovascular bundle with high variation,and the musculocutaneous nerve is blocked separately within the coracobrachialis muscle.There are many veins around the axillary artery.