肘关节体位对测量尺神经传导速度的影响

Effect of Elbow Position on Measurement of Ulnar Nerve Conduction Velocity

目的:为了解肘关节于体位改变时(完全伸展和屈曲)对尺神经在肘段和前臂段的传导率的影响。方法:对20例正常国人进行了测试。沿尺神经走行取三个刺激点:距小指外展肌记录电极8cm,尺神经沟远端和近端。结果:三个点刺激的诱发电位波幅和时限不因肘关节体位变化而受影响;但肘段的传导速度在伸肘位时明显减慢(50.62±12.20 m/s)。与前臂段(64.29±16.61 m/s)比较P<0.01,与屈肘位时(67.22±17.71 m/s)比较P<0.001。结论:在进行尺神经传导测定时应按国际标准方法取屈肘呈70度则能提高其准确性。

Objective: It is to evaluate influence of elbow position (full extention and flexion) on ulnar nerve conduction at across-elbow segment and forearm segment. Methods: Twenty normal Chinese were subjected to the survey. Three points, i.e. 8 cm proximal to the motor point of the abductor digiti quini, a point to distal to the ulnar groove and a point proximal to the ulnar groove, were stimulated. Results: The amplitude and duration of evoked potentials after stimulation at the three points were not influenced by different elbow positions, but the conduction velocity of across-elbow segment at full extension of elbow was much slower(50.62±12.20 m/s) than that of the forearm segment (64.09±16.61m/s, P<0.01) and that at 70° position of flexion (67.22±17.71, P<0.001). Conclusion: In measurement of ulnar nerve conduction velocity, more accuracy could be obtained at 70° flexion of elbow as required by international standard method.