PDF(Pubmed)
Abstract：
The variety of sources of brachial plexus injuries (BPIs) and the severity and similarity of their clinical symptoms with those of other injuries make their differential diagnosis difficult. Enriching their diagnosis with objective high-sensitivity diagnostics such as clinical neurophysiology may lead to satisfactory treatment results, and magnetic stimulation (MEP) might be an advantageous addition to the diagnostic standard of electrical stimulation used in electroneurography (ENG). The asymptomatic side in BPI cases sometimes shows only subclinical neurological deficits; this study aimed to clarify the validity and utility of using MEP vs. ENG to detect neural conduction abnormalities. Twenty patients with a BPI and twenty healthy volunteers with matching demographic and anthropometric characteristics were stimulated at their Erb\'s point in order to record the potentials evoked using magnetic and electrical stimuli to evaluate their peripheral motor neural transmission in their axillar, musculocutaneous, radial, and ulnar nerves. MEP was also used to verify the neural transmission in participants\' cervical roots following transvertebral stimulations, checking the compatibility and repeatability of the evoked potential recordings. The clinical assessment resulted in an average muscle strength of 3-1 (with a mean of 2.2), analgesia that mainly manifested in the C5-C7 spinal dermatomes, and a pain evaluation of 6-4 (mean of 5.4) on the symptomatic side using the Visual Analog Scale, with no pathological symptoms on the contralateral side. A comparison of the recorded potentials evoked with magnetic versus electrical stimuli revealed that the MEP amplitudes were usually higher, at p = 0.04-0.03, in most of the healthy volunteers\' recorded muscles than in those of the group of BPI patients, whose recordings showed that their CMAP and MEP amplitude values were lower on their more symptomatic than asymptomatic sides, at p = 0.04-0.009. In recordings following musculocutaneous and radial nerve electrical stimulation and ulnar nerve magnetic stimulation at Erb\'s point, the values of the latencies were also longer on the patient\'s asymptomatic side compared to those in the control group. The above outcomes prove the mixed axonal and demyelination natures of brachial plexus injuries. They indicate that different types of traumatic BPIs also involve the clinically asymptomatic side. Cases with predominantly median nerve lesions were detected in sensory nerve conduction studies (SNCSs). In 16 patients, electromyography revealed neurogenic damage to the deltoid and biceps muscles, with an active denervation process at work. The predominance of C5 and C6 brachial plexus injuries in the cervical root and upper/middle trunk of patients with BPI has been confirmed. A probable explanation for the bilateral symptoms of dysfunction detected via clinical neurophysiology methods in the examined BPI patients, who showed primarily unilateral damage, maybe the reaction of their internal neural spinal center\'s organization. Even when subclinical, this may explain the poor BPI treatment outcomes that sometimes occur following long-term physical therapy or surgical treatment.
摘要：
臂丛神经损伤（BPIs）的来源多种多样，其临床症状与其他损伤的严重程度和相似性使其难以鉴别诊断。用临床神经生理学等客观的高灵敏度诊断来丰富他们的诊断可能会导致满意的治疗结果，和磁刺激（MEP）可能是对神经电图（ENG）中使用的电刺激的诊断标准的有利补充。BPI病例中的无症状侧有时仅显示亚临床神经功能缺损；这项研究旨在阐明使用MEP与使用MEP的有效性和实用性。ENG检测神经传导异常。20名具有BPI的患者和20名具有匹配的人口统计学和人体测量特征的健康志愿者在他们的Erb点进行刺激，以记录使用磁和电刺激引起的电位，以评估他们的腋窝中的周围运动神经传递。肌肉皮肤，径向,尺神经.MEP还用于验证参与者在经椎刺激后的颈根中的神经传递，检查诱发电位记录的兼容性和可重复性。临床评估得出的平均肌肉力量为3-1（平均值为2.2），主要表现在C5-C7脊髓皮组的镇痛，使用视觉模拟量表对症状侧的疼痛评估为6-4（平均5.4），对侧无病理症状。记录的磁和电刺激引起的电位的比较表明，MEP振幅通常较高，在p=0.04-0.03，大多数健康志愿者记录的肌肉比BPI患者组的肌肉，他们的记录显示，他们的CMAP和MEP振幅值比无症状侧更低，p=0.04-0.009。在Erb点的肌皮神经电刺激和尺神经磁刺激后的记录中，与对照组相比，患者无症状侧的潜伏期值也更长。以上结果证明了臂丛神经损伤的轴突和脱髓鞘的混合性。他们表明不同类型的创伤性BPI也涉及临床无症状侧。在感觉神经传导研究（SNCSs）中发现了主要为正中神经病变的病例。在16名患者中，肌电图显示三角肌和二头肌的神经源性损伤，在工作中积极的去神经过程。已证实BPI患者颈根部和上/中干中C5和C6臂丛神经损伤占优势。在接受检查的BPI患者中，通过临床神经生理学方法检测到的双侧功能障碍症状的可能解释，主要表现出单方面的损害，可能是他们内部神经脊髓中心组织的反应。即使在亚临床时，这可能解释了长期物理治疗或手术治疗后BPI治疗结局不佳的原因.
