Neuroscience Research Australia & Prince of Wales Clinical School, University of New South Wales, Barker Street, Randwick, New South Wales 2031, Australia.
Muscle Nerve. 2011 Sep;44(3):402-9. doi: 10.1002/mus.22078.
In this study we investigated the changes in axonal excitability and the generation of neurological symptoms in response to focal nerve compression (FNC) of the median nerve in carpal tunnel syndrome (CTS).
Sensory excitability recordings were undertaken in 11 CTS patients with FNC being applied at the wrist using a custom-designed electrode.
During FNC, refractoriness increased significantly (62.4 ± 3.4%; P < 0.001), associated with a rapid reduction in superexcitability (16.9 ± 2.8%; P < 0.001) and sensory nerve action potential amplitude (SNAP) (32.4 ± 3.9%; P < 0.001), consistent with axonal depolarization. Associated with these changes, paresthesiae steadily increased throughout FNC, as did numbness. Reductions in SNAP amplitude and superexcitability developed more rapidly for CTS patients during FNC compared with controls, and these changes were associated with more marked symptoms.
Axonal responses to compression are impaired in CTS. This may suggest a greater reliance on axonal membrane Na(+) /K(+) -ATPase function.
本研究通过对腕部正中神经压迫(FNC)的检测,探讨正中神经腕管综合征(CTS)中轴突兴奋性变化与神经症状的产生。
通过定制电极在 11 名 CTS 患者上进行感觉兴奋性记录,施加 FNC。
FNC 期间,不应期显著增加(62.4±3.4%;P<0.001),伴有超兴奋性迅速降低(16.9±2.8%;P<0.001)和感觉神经动作电位幅度(SNAP)降低(32.4±3.9%;P<0.001),与轴突去极化一致。与这些变化相关,在 FNC 过程中,感觉异常逐渐增加,麻木也逐渐增加。与对照组相比,CTS 患者在 FNC 期间 SNAP 幅度和超兴奋性的降低更快,这些变化与更明显的症状相关。
CTS 患者对压迫的轴突反应受损。这可能表明对轴突膜 Na(+) /K(+) -ATP 酶功能的依赖性更大。