Correlation between electromyography findings and plasticity grading score after long-term phrenic nerve to musculocutaneous nerve transfer in brachial plexus injuries.
Simon Miedema, Francisco Vargas, Eugenia Conti, Martin Bourguet, Martijn Malessy, Mariano Socolovsky
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引用次数: 0
Abstract
Objective: Patients with complete traumatic brachial plexus injuries often require nerve transfers to restore lost function. Phrenic nerve (PN)-musculocutaneous nerve (MCN) transfer can be used to restore elbow flexion. The degree to which reinnervated muscles achieve independent control requires central plastic changes. The central program of the PN donor nerve needs to disconnect and establish connections with that of the recipient MCN. This study aimed to improve understanding of the brain's changes after PN-MCN transfer by correlating electromyography (EMG) findings with clinical plasticity grading scale (PGS) scores.
Methods: A prospective study was conducted on patients who underwent PN-MCN transfer after brachial plexus injury. EMG assessments were systematically performed under 3 distinct conditions: 1) normal respiration with the arm at rest, 2) deep respiration with the arm at rest, and 3) voluntary elbow flexion performed without inspiration. Motor unit potentials (MUPs) detected within a 150-msec interval were systematically categorized using a 5-point scale. Brain plasticity was clinically evaluated using the 4-point PGS.
Results: Twelve patients with a mean age of 21.8 years were included in the study. A significant negative correlation was found between EMG activity during deep breathing and PGS outcomes (correlation coefficient [CC] -0.623, p = 0.031). Likewise, EMG activity during deep breathing showed a negative correlation with EMG activity during voluntary elbow flexion (CC -0.811, p = 0.002). Only 1 patient (8%) demonstrated complete disconnection between the donor and recipient neural pathways.
Conclusions: The authors' findings indicate a significant correlation between clinical measures of brain plasticity and EMG outcomes. Additionally, complete cerebral disconnection was rarely attained, with most patients retaining residual influence from the original donor function.
目的:完全性外伤性臂丛神经损伤患者通常需要神经移植来恢复失去的功能。膈神经(PN)-肌皮神经(MCN)移植可用于肘关节屈曲恢复。再神经支配肌肉达到独立控制的程度需要中枢可塑性的改变。PN供体神经的中心程序需要断开并与受体MCN建立连接。本研究旨在通过将肌电图(EMG)结果与临床可塑性评分(PGS)评分相关联,提高对PN-MCN转移后大脑变化的认识。方法:对臂丛神经损伤后行PN-MCN转移的患者进行前瞻性研究。在3种不同的条件下系统地进行肌电图评估:1)手臂静止时的正常呼吸,2)手臂静止时的深度呼吸,以及3)在没有吸气的情况下进行肘部自主屈曲。在150毫秒间隔内检测到的运动单位电位(MUPs)采用5分制进行系统分类。临床应用4点PGS评价脑可塑性。结果:12例患者被纳入研究,平均年龄21.8岁。深呼吸时肌电活动与PGS结果呈显著负相关(相关系数[CC] -0.623, p = 0.031)。同样,深呼吸时的肌电图活动与随意屈肘时的肌电图活动呈负相关(CC -0.811, p = 0.002)。只有1例患者(8%)表现出供体和受体神经通路完全断开。结论:作者的研究结果表明,脑可塑性的临床测量与肌电图结果之间存在显著相关性。此外,完全的脑断连很少实现,大多数患者保留了原始供体功能的残余影响。