| 摘要: | 上肢疼痛麻木是門診病人常見之主訴，最常見的是腕隧道症候群 (carpal tunnel syndrome, CTS)。因正中神經在手腕隧道處長期受到壓迫所引起，嚴重時將造成大拇指肌肉的萎縮。臨床上也常發現CTS伴隨頸椎神經根病變(cervical radiculopathy, CR)，若單側神經軸有2處同時受壓迫，則稱為double crush syndrome, DCS。然而國內學者卻未有這相關方面的研究顯示DCS是否會更顯著影響神經傳導功能，我國雖有訂定診斷CTS的標準，但臨床專科或是非專科醫師判斷是否一致，選用診斷方法是否有良好之敏感性與特異性，與電生理檢查是否有良好之相關性均有待進一步之研究探討。研究目的 (1)探討CTS、CR及DCS之臨床症狀與電生理學檢查之關係，(2)評估CT理學檢查之敏感性與特異性，(3)推估國人高科技年輕電腦工作族群之CTS罹患率，並分析其風險因子。
首先本研究分析中部某醫學中心自民國90年1月至97年2月之病歷資料，共866人參與電生理檢查之個案，結果顯示罹患CTS和DCS者分別與R’t median motor distal latency (RMDL)及L’t median motor distal latency (LMDL)有中度正相關 (r =0.34～0.55)，而分別與R’t median nerve conduction velocity across mid palm (R’t mNCV)及L’t median nerve con-duction velocity across mid palm (L’t mNCV)為中度負相關 (r= -0.32～-0.40)，且均達統計上顯著性 (p<0.01)，而CR患者與任何電生理指標無顯著相關。對照組、CTS及DCS患者之運動神經RMDL與LMDL分別為4.55 vs. 4.75 vs. 4.91 ms與3.33 vs. 4.64 vs. 5.53 ms且均具顯著差異 (p=0.0001)，對照組、CTS及DCS患者之感覺神經傳導速度R’t mNCV與L’t mNCV分別為38.10 vs. 32.16 vs. 29.80 m/sec與41.54 vs. 33.44 vs. 30.42 m/sec且兩者均具顯著差異 (p<0.01)。說明同時壓迫2個地方時，會導致更嚴重之神經傳導阻礙。進一步以CTS電生理檢查為gold stan-dard，理學檢查Tinel’s sign之敏感性為90.2%，特異性為5.3%，Phalen’s test 敏感性為85.4%，特異性為5.9%，顯示Tinel’s sign與Phalen’s test敏感性佳，但低估其特異性，可能原因為問診判斷為健康者並未實施理學檢查，或實施理學檢查後發現為陰性結果，而未作紀錄。
另一方面本研究擬訂一般電腦工作族群之「疼痛感知及自覺症狀問卷」，於民國97年9月至98年4月調查中部地區特定工作族群共473位，結果顯示CTS盛行率為11.2%，個案組於每週工作使用鍵盤時數及滑鼠(44.3 vs. 44.6小時/週)均比對照組時間長 (39.5 vs. 39.6小時/週)，且皆達統計上顯著意義 (p<0.05)。進一步以logistic regression分析CTS風險因子，顯示工作年資 (月)OR為1.00倍 (95% CI=1.00-1.01)，而每週工作使用滑鼠OR為1.02倍 (95% CI=1.00-1.03)，表示工作年資越長，工作使用滑鼠時間越久，其罹患CTS風險越高，且達統計上顯著意義 (p<0.05)。
本研究受限於病歷就診個案之CTS (n=151)與DCS (n=198)人數較少，加上電生理檢測未標準化，遺漏檢測或未能詳盡登錄病歷，建議研擬CTS診斷標準表，以減少撰寫病歷資料的時間，減少診斷差異，提昇問診品質。
Upper limb pain and numbness are the frequent complaints of patients with carpal tunnel syndrome (CTS) which is the most common peripheral nerve compression syndrome. In this disease, the median nerve is compressed in carpal tunnel and cause symptoms of sensory abnormality, and even muscle hand muscle atrophy in the severe cases. If concomittent development of cervical radiculopathy (CR) and carpal tunnel syndrome occurred, double crush syndrome (DCS) resulted. In the past, the domestic scholar seldom investigated or discussed whether the DCS has remarkable influence on nerve conduction function. Although there are diagnostic criteria of CTS in our country, but the inconsistence of clinical diagnosis exist between different physicians. This discrepancy may be related to the variation of history taking, physical examination, the technique of electrophysiology study employed and electrodiagnostic criteria used. In view of the above findings, we carry on a serial of studies including: (1) investigation of the relationship between electrodiagonstic examination and the clinical charaterictis of CTS/CR/DCS, (2) evaluation of sensitivity and specificity of physiological diagnosis methods of CTS, (3) investigation of proportion of CTS in young computer vediodisplay terminal (VDT) user of the high technology industry group and the analysis of the risk factors among them.
We retrospectively reviewed the electrodiagnostic records and medical records of 886 patients from a medical center in the mid-Taiwan from the year 2001 to 2008. The results indicated that CTS and DCS were moderate positively correlated (r =0.34～0.55) with right median motor distal latency (RMDL) and left median motor distal latency (LMDL) (p<0.01) respectively ; moderate negatively correlated (r = -0.32～0.40 ) with right median sensory nerve conduction velocity across mid palm (R''t mNCV) and L''t median nerve conduction velocity across mid palm (L''t mNCV), (p<0.01) respectively. Hower, CR was not significantly correlated with any electrodiagnostical indicator. Significant delay of RMDL from control to CTS to DCS groups were found when comparison among the three groups were made ( 4.55 vs 4.75 vs 4.91 ms, p=0.0001), similarly significant delay of LMDL from control to CTS to DCS groups were also found when comparison among the three groups were made ( 3.33 vs 4.64 vs 5.53 ms, p=0.0001). Significant decrement of R’t mNCV across the control, CTS and DCS groups were found when comparison among the three groups were made (38.10 vs 32.16 vs 29.80 m/sec, p< 0.01), similarly significant decrement of L’t mNCV across the control, CTS and DCS groups were also found when comparison among the three groups were made (41.54 vs 33.44 vs 30.42 m/sec, p< 0.01). These findings may explain the double crush syndrome hypothesis in that more than one compressive lesion along the nerve will further compromise the nerve conduction function. When nerve conduction study is used as the gold standard of CTS diagnosis, the sensitive and specificity of Tinel''s sign are 90.2% and 5.3% , while that of Phalen''s test are 85.4% and 5.9% respectively. The result indicates that Tinel''s sign and Phalen''s test have high sensitive but low specificity. The unexpected low specificity of the Tinel''s sign and Phalen''s test may be due to lack of detail physical examination in patients without specific symptoms or physicians accustomed not to record the numerous negative findings in the clinical practice with limited time devoted to each patients in the ambulatory settings.
The other part of our research involving the development of a questionnaire to evaluate the prevalence of CTS in young computer vediodisplay terminal user of the high technology industry. From September 2008 to April 2009, 473 employee of the high technology industry in mid-Taiwan were enrolled in our study. The proportion of CTS in this occupational group was found to be 11.2%. People with CTS were found to have significantly longer hours of keyboard (44.3 vs. 39.5 hours/week, p<0.05) and mouse (44.6vs. 39.6 hours/week, p<0.05) use when compared to people without CTS. Further analysis of the CTS risk factor by logistic regression, demonstrated that the OR of occupational duration (month) is 1.00, (p<0.05, 95% CI=1.00-1.01), and that of mouse use during working hour per week is 1.02, (p<0.05, 95% CI=1.00-1.03), indicated that the risk of CTS increases with the duration of the occupation and frequency of keyboard and mouse use.
In our present study, the following limitations are encountered:(1) the sample size included in the electrodiagnostic and medical record review is not large enough, (2) minor variation in the electrodiagnostic criteria used for the diagnosis of CTS may exist among different physiatrists, (3) the inadequacy of recording of negative clinical examination findings in clinical practice. Further prospective large scale clinical and occupational studies are needed to further support the findings in our present study. Furthermore the development of effective standardize clinical evaluation questionnaire also have crucial role in further studies and diagnosis of carpal tunnel syndrome. |
