The Effect of Static Wrist Position on Median Nerve over Six Hours

固定手腕姿勢六小時對正中神經之影響

10.6315/2014.42(1)06

徐菁寧(Ching-Ning Hsu)；楊育昇(Yu-Sheng Yang)；許瑞仁(Jui-Jen Hsu)；蔡伊純(Yi-Chun Tsai)；林沛華(Pei-Hua Lin)；李佳玲(Chia-Ling Lee)

腕隧道症候群 ； 副木 ； 超音波 ； 神經傳導研究 ； 手腕姿勢 ； carpal tunnel syndrome ； splint ； ultrasonography ； nerve conduction study ； wrist posture

台灣復健醫學雜誌

42卷1期（2014 / 03 / 01）

51 - 61

英文

腕隧道症候群是最常見圈閉神經病變，成因於正中神經於手腕附近的腕隧道受到壓迫。本研究的目的則在探討六小時的擺位，不同手腕伸直姿勢對正中神經影像上及神經傳導上的影響。我們針對40個健康者的手腕及32個腕隧道症候群患者的手腕進行調查。在兩組內，個案隨機戴上不同角度的副木，以固定於0、15、30及45度的腕部伸展。戴上副木前先進行一次超音波檢查，並分別於穿戴後隨即再進行施測，之後個案仍持續戴著副木，並分別在穿戴後兩小時、四小時、以及六小時後，重覆施測一次。在超音波檢查中，正中神經的扁平率及橫切面面積被檢驗；在神經傳導檢查中，我們在穿戴副木前先進行施測，並分別在穿戴後兩小時、四小時、以及六小時後，重覆施測一次，正中神經運動及感覺傳導的部份亦被檢視。結果顯示當手腕擺位在中立的位置上，隨著時間增加正中神經會受到最小的壓力。反之，當手腕擺位在伸直位置上，在腕隧道近端的正中神經會有形態上扁平的顯著改變。然而在神經傳導檢查上卻無顯著的變化。正確的手腕姿勢是防止正中神經受壓一個非常重要的因素，而超音波檢查發現對於早期檢測正中神經受壓現象具有較高的敏感度。

Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy, caused by the compression of the median nerve in the carpal tunnel over the wrist. The purpose of this study is to demonstrate how different wrist positions change median nerve image and their corresponding results of nerve conduction study (NCS). In this study, we investigated 40 normal wrists and 32 wrists with CTS. In both groups, subjects were randomly assigned to wear a splint, and the wrist was placed at 0, 15, 30 and 45 degrees of extension. Ultrasonography was performed before splinting, immediately after splinting and repeated again 2, 4 and 6 hours later. Ultrasonographic examination evaluated the flattening ratio and cross-sectional area of the median nerve at carpal tunnel. NCS was performed before splinting and repeated again 2, 4 and 6 hours later. The motor and sensory components of nerve conduction over median nerve were tested. The results showed that the neutral position was associated with the lowest median nerve compression over time. All the extended wrist positions were associated with significant median nerve flattening at the proximal carpal tunnel level. But there were no significant electrophysiological differences between different wrist positions. The proper wrist position is a very important factor in preventing median nerve compression, and the ultrasonographic finding is more sensitive for earlier detection concerning median nerve compression.