臂丛神经损伤后副神经的电生理改变及其对斜方肌功能的影响

背景副神经移位修复肩胛上神经,常用于重建臂丛损伤患者的肩外展功能.但是副神经移位后对斜方肌的功能影响及岗上、下肌新生电位出现时间尚不清楚.目的观察臂丛损伤患者在锁骨下水平切断副神经并移位到肩上神经后,其斜方肌不同部位的电生理改变.设计以诊断为依据的自身对照的回顾性研究.地点和对象实验地点为复旦大学华山医院手外科,实验对象1996-01/2000-02进行副神经移位修复肩胛上神经的臂丛神经损伤患者,资料完整的20例作为研究对象.其中男17例,女3例;年龄11～46岁,平均29岁.方法20例臂丛损伤患者伤后3～6个月,于锁骨下水平切断副神经移位到肩上神经.应用PHASIS电生理仪,在颈部胸锁乳突肌前放置刺激电极,在斜方肌上、中、下部及胸锁乳突肌进行记录,同时对术后岗上、下肌进行动态肌电检测及功能随访.主要观察指标斜方肌术前、术后肌力检查,上、中、下动作电位波幅值、患肢外展功能.结果在锁骨下水平切断副神经移位到肩上神经,对斜方肌下部功能影响明显,对中上部无明显影响.83.3%的患者术后5～9个月冈上肌可检测到神经再生电位,经术后2～3年随访此组患者均恢复了肩外展功能.结论在锁骨下水平切断副神经移位后,主要影响斜方肌下部功能,对上、中部无明显影响.斜方肌严重损伤的患者如果胸锁乳突肌功能良好,副神经仍可作为供区.

Electrophysiological change of accessory nerve after brachial plexus injury and its effects on the function of trapezius

BACKGROUND: Transferring accessory nerve to suprescapular nerve is regularly adopted to reconstruct shoulder abduction of the patients with brachial plexus lesion. But it is not clarified yet if the function of trapezius will be interfered with and when the newborn potentials of supraapinatus and infraapinatus appear after the transferring procedure.OBJECTIVE: To investigate the pre-end postoperative electrophysiological changes of the different sites of trapezius and its effect on the function of trapezius of the patients with brechial plexus injury whose accessory nerves were sectioned at the infraclavicular level and transferred to suprascapular nerves during operation.DESIGN: An auto-control retrospective study waa performed according to the diagnosis.SETTING and PARTICIPANTS: The experiment was carried out in the Department of Hand Surgery of Huashen Hospital, Ftidan University. During January, 1996 and February, 2000, the accessory nerves of patienta with brachial plexus injury were transferred to suprascapuler nerves, and 17 men end 3 women of these patients with full data, aged 11 to 46 years, with a mean age of 29 years old were selected aa the aubjects.METHODS: The accessory nerve of these 20 patients was sectioned at infraclavicular level and transferred to suprascapular nerve 3 to 6 months after injury. PHASIS was used for electrophysiological examination. The stimulating electrode was placed over the snrface of aternocleidomastoid muscle, and the record was made at the upper, middle end lower part of trapezius muscle and sternocleidomustoid muscle. The dynamic EMG end functional following-up were carried out at the supraspinatus and infraspinatus postoperatively.MAIN OUTCOME MEASUREMENTS: The testing of muscle strength before and after operation was performed, and the amplitude values of action potential of the upper, middle and lower part of trapezius muscle, and the abduction of affected extremity were measured.RESULTS: Sectioning and transferring of accessory nerve at infraclavicular level disturbed the function of the lower part of trapezius muscle obviously,while there was no significant effect on the upper and middle parts. The neural regeneration action potential of supraapinatus of 83.8% patients was detected 5-9 months after operation. All the patients in this group regained their function of shoulder abduction 2-3 years later.CONCLUSION: Sectioning accessory nerve at the infraclavicular level would interfere with the function of the lower part of trapezius muscle. If sternocleidomaatoid muscle possessea good function, the prorimal accessory nerve close to the branch innervating the sternocleidomastnid muscle can still be selected as a donor nerve in spite of the severe paralysis of trapezius muscle.