Department of Hand Surgery, Huashan Hospital, Fudan University, Shanghai, China.
Department of Hand and Upper Extremity Surgery, Jing'an District Central Hospital, Fudan University, Shanghai, China.
Brain Behav. 2021 Apr;11(4):e02064. doi: 10.1002/brb3.2064. Epub 2021 Feb 6.
Contralateral cervical seventh (C7) nerve transfer aids motor and sensory recovery in total brachial plexus avulsion injuries (TBPI), but synchronous sensation often persists postoperatively. The mechanism underlying synchronous sensory phenomena remain largely unknown.
To investigate the role of central plasticity in sensory recovery after contralateral C7 nerve transfer.
Sixteen right TBPI patients who received contralateral C7 nerve transfer for more than 2 years were included. Sensory evaluations included Semmes-Weinstein monofilament assessment (SWM), synchronous sensation test, and sensory evoked action potential (SNAP) test. Smaller value in the SWM assessment and larger amplitude of SNAP indicates better tactile sensory. Functional magnetic resonance imaging was performed while stimulations delivered to each hand separately in block-design trials for central plasticity analysis.
The SWM value of the injured right hand was increased compared with the healthy left side (difference: 1.76, 95% confidence interval: 1.37-2.15, p < .001), and all 16 patients developed synchronous sensation. In functional magnetic resonance imaging analysis, sensory representative areas of the injured right hand were located in its ipsilateral S1, and 23.4% of this area overlapped with the representative area of the left hand. The ratio of overlap for each patient was significantly correlated with SWM value and SNAP amplitude of the right hand.
The tactile sensory functioning of the injured hand was dominated by its ipsilateral SI in long-term observation, and its representative area largely overlapped with the representative area of the intact hand, which possibly reflected a key mechanism of synchronous sensation in patients with TBPI after contralateral C7 transfer.
对全臂丛神经根性撕脱伤（TBPI）患者施行健侧 C7 神经移位术可辅助运动和感觉恢复，但术后常持续存在感觉同步现象。感觉同步现象的发生机制仍知之甚少。
探讨 C7 神经移位术后感觉恢复的中枢可塑性作用。
纳入 16 例接受健侧 C7 神经移位术且时间超过 2 年的右 TBPI 患者。感觉评估包括 Semmes-Weinstein 单丝评估（SWM）、感觉同步测试和感觉诱发电位（SNAP）测试。SWM 评估值越小，SNAP 振幅越大，提示触觉感觉越好。采用功能磁共振成像在块设计试验中分别刺激双手，进行中枢可塑性分析。
与健侧左手相比，患侧右手的 SWM 值增加（差值：1.76，95%置信区间：1.37-2.15，p<0.001），16 例患者均出现感觉同步。在功能磁共振成像分析中，患侧右手的感觉代表区位于同侧 S1，其中 23.4%的区域与左手的代表区重叠。每位患者的重叠比例与右手的 SWM 值和 SNAP 振幅呈显著相关。
长期观察发现，患手的触觉感觉功能由其同侧的 S1 主导，其代表区与健手的代表区大部分重叠，这可能反映了 TBPI 患者接受健侧 C7 神经移位术后感觉同步的关键机制。
