平山病的临床神经电生理学特点

目的:探讨平山病的临床神经电生理学特点及其可能的发病机制。方法:对45例平山病患者进行神经传导速度、F波以及针极肌电图检测。结果:神经传导速度测定总异常率为24.4%(44/180),主要表现为运动神经DML延长以及CMAP波幅减低,感觉神经传导速度均正常。F波平均最小潜伏期为(26.64±3.10)ms,平均出现率为(58.77±35.53)%,总异常率为75.6%(34/45)。针极肌电图检测中57.7%表现为神经源性损害,主要异常为出现自发电位,MUPs时限延长、波幅增宽、多相波增多,募集相异常。前臂肌肉的异常率为患侧伸指总肌(100%)≥健侧伸指总肌(100%)>患侧拇短展肌(97.8%)>患侧小指展肌(97.7%)>健侧拇短展肌(82.6%)>患侧肱二头肌(75.0%)。双侧三角肌、健侧肱二头肌、下肢胫骨前肌、胸锁乳突肌肌电图正常。结论:根据平山病临床神经电生理学表现推测平山病可能为颈段脊髓病变。

Clinical Neuroelectrophysiological Characteristics of Hirayama Disease

ObjectIive:To study the clinical neuroelectrophysiological characteristic of Hirayama disease and its possible pathogenesis.Methods:Nerve conduction velocity(NCV),F-wave and needle-electromyography(EMG)were performed in all 45 patients who have been diagnosed to have Hirayama disease on the clinical ground.Results:The abnormality rate of the NCV in 180 examined nerves was 24.4%,predominantly in the motor nerves,characterized by the delay of distal motor latency(DML)and the diminution of the compound muscle action potential(CMAP).The sensory conduction velocity(SCV)study showed no abnormality.The mean minimal latency of F-wave in 45 median nerves was(26.64±3.10)ms with the mean persistence rate of 58.77%.The total abnormality of NCV was 75.6%(34/45).Out of the examined muscles,57.7% displayed neurogenic changes,including spontaneous potentials,motor unit potentials(MUPs)changes(the increase of latency,the augment of the amplitude,the increase of the polyphasic waves,and the pattern of the recruitment).The muscles in the forearm were affected as the following order:the affected extensor muscle of fingers(100%);the asymptomatic extensor muscle of fingers(100%);the affected short abductor muscle of thumb(97.8%);the affected abductor muscle of little finger(97.7%);the asymptomatic short abductor muscle of thumb(82.6%);and the affected biceps muscle of arm(75.0%).No abnormality was observed in the bilateral deltoid muscles,the biceps muscle on the un-affected side,anterior tibial muscles,and sternocleidomastoid muscles.Conclusion:Our data suggested that Hirayama disease may be a special type of cervical myelopathy.