Chen Li, Chen Jie, Hu Bing, Jiang Li-Xin
Department of Ultrasound in Medicine, Shanghai Jiaotong University Affiliated Sixth People's Hospital, Shanghai Institute of Ultrasound in Medicine, Shanghai, China.
Clinics (Sao Paulo). 2017 Jun;72(6):358-362. doi: 10.6061/clinics/2017(06)05.
: The aim of this study was to investigate the prevalence of anatomic variations of the bifid median nerve, persistent median artery and persistent median vein in Chinese individuals and their relationship with carpal tunnel syndrome.
: One hundred and sixty median nerves were examined using ultrasonography and colour Doppler ultrasonography. The location, shape, and size of the bifid median nerve, persistent median artery and persistent median vein were recorded. The cross-sectional area of the bifid median nerve (two trunks) was measured at the level of the pisiform.
: Among the 160 wrists examined, a bifid median nerve was observed in 15 (9.4%) wrists, and a persistent median artery was observed in 12 (7.5%) wrists. These two variations either coexisted or were observed independently, and the probability of coexistence (6.3%) was higher than the probability of existing independently (bifid median nerve only 3.1%, persistent median artery only 1.3%). The cross-sectional area of the radial trunk was greater than (13 in 15, 86.7%) the cross-sectional area of the ulnaris trunk. Persistent median vein was observed in 9 wrists (5.6%).
: The persistent median artery and bifid median nerve tend to coexist, and the persistent median vein sometimes runs parallel to the persistent median artery. Their positional relationship in carpal tunnel is uncertain, and thus, preoperative ultrasound is necessary. These three variations do not present any additional risk for the development of carpal tunnel syndrome.
本研究旨在调查中国人群中正中神经分叉、正中动脉永存及正中静脉永存的解剖变异发生率及其与腕管综合征的关系。
采用超声及彩色多普勒超声检查160条正中神经。记录正中神经分叉、正中动脉永存及正中静脉永存的位置、形态和大小。在豌豆骨水平测量正中神经分叉（双干）的横截面积。
在160例受检腕关节中，15例（9.4%）发现正中神经分叉，12例（7.5%）发现正中动脉永存。这两种变异可同时存在或单独出现，且同时存在的概率（6.3%）高于单独出现的概率（仅正中神经分叉3.1%，仅正中动脉永存1.3%）。桡侧干的横截面积大于尺侧干（15例中有13例，86.7%）。9例腕关节（5.6%）发现正中静脉永存。
正中动脉永存与正中神经分叉倾向于同时存在，正中静脉永存有时与正中动脉永存并行。它们在腕管内的位置关系尚不确定，因此术前超声检查是必要的。这三种变异并未增加腕管综合征发生的额外风险。
