Dyck P J, Lambert E H, Wood M B, Linscheid R L
Peripheral Nerve Laboratory, Mayo Clinic, Rochester, MN 55905.
Neurology. 1988 Oct;38(10):1586-91. doi: 10.1212/wnl.38.10.1586.
Six patients with median nerve severance (five sutured) were studied after an interval of 1.8 to 35 years to assess residual neurologic deficit, misdirected axonal regrowth, and adaptation to faulty reinnervation. Mild motor impairment was confirmed by the smaller thenar muscle action potentials and isometric muscle twitches from supramaximal stimulation of the median nerve. Sensory impairment was supported by the increased thresholds of vibratory (p = 0.003) and touch-pressure (p = 0.004) detection thresholds of the pulp of index fingers and decreased amplitudes of sensory nerve action potentials. A tactile hemidigit localization test revealed that localization was not significantly different from that on the contralateral side but perceptual territory was increased. This increase is best explained by misdirected axon regrowth without CNS adaptation. Long-standing faculty tactile digit localization in neurovascular skin flaps from finger to thumb also was demonstrated--further evidence that CNS adaptation is imperfect when sensory nerves to digits are relocated.
对6例正中神经离断患者（5例已缝合）进行了研究，时间间隔为1.8至35年，以评估残留神经功能缺损、轴突再生错误以及对错误再支配的适应情况。通过较小的鱼际肌动作电位和正中神经超强刺激引起的等长肌肉抽搐证实了轻度运动障碍。食指指腹振动觉（p = 0.003）和轻触压觉（p = 0.004）检测阈值升高以及感觉神经动作电位幅度降低支持了感觉障碍。触觉半指定位测试显示，定位与对侧相比无显著差异，但感觉区域增加。这种增加最好用轴突再生错误且中枢神经系统未适应来解释。还证实了在从手指到拇指的神经血管皮瓣中长期存在的触觉手指定位功能障碍——这进一步证明，当手指的感觉神经重新定位时，中枢神经系统的适应并不完美。
