腕隧道症候群的影像學診斷、運動治療及人因工程危險因子之探討

Imaging Diagnosis, Therapeutic Exercise and Ergonomic Risk Factors in Patients with Carpal Tunnel Syndrome

洪怡珣(Yi-Shiung Horng)

指導教授 ： 王榮德

國立臺灣大學/公共衛生學院/職業醫學與工業衛生研究所/博士(2011年)

https://doi.org/10.6342/NTU.2011.02394

摘要

腕隧道症候群是常見的職業性神經疾病，好發於諸多須手腕部重複性動作或過度用力的行業，其不只造成手部麻木無力而影響生活品質，並會降低生產力而造成經濟損失。因此，為了改善病人之生活品質及生產力，臨床工作者應有適當的診斷及評估工具，以提出最具療效的治療方法。
傳統上腕隧道症候群的診斷標準包括：臨床症狀、理學檢查以及神經電學檢查。然而研究顯示，臨床診斷為腕隧道症候群之病人，其神經傳導檢查具有偽陰性的比例約為百分之十至三十。近年來超音波及核磁共振等影像學檢查，常被應用於腕隧道症候群之診斷，但是鮮少有研究針對不同影像學檢查的診斷正確性進行比較。
針對腕隧道症候群病人之保守治療，臨床上經常合併肌腱及神經滑動運動，但根據過去的研究，其效果尚無定論。本研究認為，欲針對治療效果進行較好的評估，除了臨床檢查項目外，應加入病人自評問卷等工具，以反應出對病人有意義之最小變化值。有鑑於此，本研究藉由比較不同評估、診斷工具以及運動治療方式，並探討腕隧道症候群的人因工程危險因子，以對臨床治療提出建議，達到改善病人之症狀、功能、限制以及生活品質之目的。為了達到此目的，本論文包括以下四個系列研究：
第一個研究之目的為比較密西根手功能問卷和DASH上肢失能問卷於手外傷病人之反應性。共有105位手外傷病人參與該研究，其中50位於復健2個月之後接受追蹤評估。研究結果顯示，密西根手功能問卷之效果值及標準化反應之平均值分別為0.84和1.05，而DASH上肢失能問卷則為0.67 和0.86，換言之，密西根手功能問卷的反應性較好。當控制年齡、性別及心理因素後，密西根手功能問卷每增加3.2分或DASH上肢失能問卷減少3.3分，可改善一單位之健康相關生活品質滿意程度。此外，密西根手功能問卷與手功能之變化較有相關，而DASH上肢失能問卷與失能天數較有關；心理因素則是健康相關生活品質與失能狀態最強之預測因子。
第二個研究試圖比較於手部休息及握拳二種姿勢，進行核磁共振造影或超音波檢查，二者在腕隧道症候群之診斷正確性。本研究針對50位腕隧道症候群患者及45位健康人，給予臨床評估、問卷調查、神經傳導檢查、核磁共振造影以及超音波檢查。ROC曲線分析結果顯示，以正中神經的截面積為診斷標準之敏感性、特異性以及曲線下面積，在核磁共振檢查的結果為0.74, 0.88, 0.84；而超音波檢查的結果為0.63, 0.86, 0.80。比較手部休息及握拳二種姿勢進行核磁共振造影或超音波檢查結果顯示，當結合正中神經截面積以及屈肌支持帶彎曲程度兩個診斷標準時，可得到最高之曲線下面積：核磁共振造影的曲線下面積於手部休息及握拳姿勢分別提高至0.87及0.89。而藉由結合手部休息姿勢下之正中神經截面積以及握拳姿勢下之屈肌支持帶彎曲程度兩個診斷標準，超音波的曲線下面積可由0.80提高至0.83。因為於握拳姿勢進行檢查可提高以屈肌支持帶彎曲程度為診斷標準之曲線下面積，因此當結合手部休息姿勢下之正中神經截面積以及握拳姿勢下之屈肌支持帶彎曲程度兩個診斷標準，超音波的診斷正確性可提高而作為診斷腕隧道症候群的初步篩選工具。
第三個研究針對肌腱滑動運動與神經滑動運動於腕隧道症候羣之臨床療效進行比較。本研究採前瞻性研究，針對腕隧道症候群之病人，給予臨床評估(肌力和感覺測試)以及神經傳導檢查；同時對每位病人施行自填式問卷調查，內容包括基本資料、波士頓腕隧道症候羣問卷、DASH上肢失能問卷以及簡明版世界衛生組織生活品質問卷。除此之外，並將病人隨機分為三組，控制組只給蠟療及副木治療，實驗組一組接受蠟療、副木及肌腱滑動運動，另一組接受蠟療、副木及神經滑動運動；二個月後再進行一次臨床評估及問卷調查，並且追蹤紀錄受試者在神經傳導檢查上之變化狀況。共有60位病人參與本研究，其中53位完成治療以及追蹤檢查。研究結果顯示，雖然所有病人之症狀及疼痛指數在治療後皆有顯著改善，然而其中只有接受蠟療、副木及肌腱滑動運動的病人，在上肢功能以及生活品質上有顯著進步。此外，實驗組之第一組與第二組在手功能之改善程度上有顯著差異，此一結果顯示，就治療效果而言，同時接受蠟療、副木及肌腱滑動運動較同時接受蠟療、副木及神經滑動運動的效果為佳。
第四個研究之目的為探討女性腕隧道症候羣病人之人因工程以及人體計測危險因子。本研究針對45位腕隧道症候群患者及40位健康人，給予臨床評估、問卷調查、神經傳導檢查、核磁共振檢查以及人因工程危險因子調查。研究結果顯示，腕隧道症候群患者及健康人，在上述臨床評估、問卷調查、神經傳導檢查、核磁共振造影檢查以及人因工程危險因子方面皆有統計上顯著差異。以廣義估計方程式分析顯示，於控制年齡、身體質量指數下，正中神經以及腕隧道之截面積比例(勝算比 1.90, 95%信賴區間 1.40-2.57)、標準化最大施力(normalized peak force；勝算比 1.50, 95%信賴區間 1.21-1.87)以及人因工程危險因子指數(勝算比 1.86, 95%信賴區間1.30-2.64)與腕隧道症候群之發生皆有顯著相關。

關鍵字

職業性腕隧道症候群 ； 密西根手功能問卷 ； DASH上肢失能問卷 ； 肌腱滑動運動 ； 神經滑動運動 ； 超音波檢查 ； 核磁共振造影檢查 ； 人因工程危險因子

並列摘要

Carpal tunnel syndrome (CTS) is one of the most common occupational entrapment neuropathies which could induce productivity loss and deteriorate the quality of life of workers. For the purpose of reducing productivity loss and improving the quality of life of patients with CTS, it is important for the clinicians to evaluate the risk factors, to establish a protocol for making early diagnosis, and to provide the most effective treatments and interventional programs.
Conventionally, clinical symptoms/signs and electrophysiological tests have been applied together to diagnosing CTS. However, the consensus of diagnostic criteria for CTS has not been achieved because there are some limitations of the nerve conduction study (NCS). And imaging diagnoses such as ultrasonography and magnetic resonance imaging (MRI) study have been applied for the diagnosis of CTS recently. In the treatment of CTS, therapeutic exercises have been applied but their effectiveness varied in different studies. For providing effective interventional programs, patient reported outcomes should be incorporated with clinical measurement to reflect the clinically important differences for the patients. The ultimate goal of this study is to help improve the symptoms, functions and the quality of life of the patients with CTS through making early diagnosis, recognizing ergonomic risk factors and proposing better ways of doing evaluation on the effectiveness of intervention. To approach this goal, four related studies have been undertaken.
In the first study, we assessed the responsiveness of the Michigan Hand Outcomes Questionnaire (MHQ) and the Disability of Arm, Shoulder, and Hand (DASH) Questionnaire in the patients with hand injury and compared the results with those applied in patients with CTS. A total of 105 patients with hand injuries were recruited, and 50 of them returned for the second evaluation. Responsiveness was evaluated by effect sizes and standardized response means, of which the MHQ were 0.84 and 1.05, and DASH were 0.67 and 0.86, respectively. The results revealed that the MHQ might be slightly more sensitive to functional changes, but the DASH questionnaire seemed more correlated to disability days. Psychological factors are the strongest determinants of the HRQOL and disability.
The accuracy difference between ultrasonography and MRI in diagnosing CTS at rest and grasp positions were explored in the second study. 50 Patients with CTS and 45 healthy volunteers were recruited. Every participant received a package of questionnaire, physical examinations, NCS, sonography and MRI examinations. The results revealed that the sensitivity, specificity and area under the receiver operating characteristic curve (AUC) in diagnosing CTS for cross sectional area of median nerve measured by MRI and ultrasonography were 0.74, 0.88, 0.84 and 0.63, 0.86, 0.80 respectively. The combination of cross sectional area and bowing of the flexor retinaculum yielded the highest AUC for MRI, recorded from both rest and grasp positions (0.87 and 0.89 respectively). The AUC of ultrasonography of cross-section area measured at pisiform level under rest position was 0.80, which can be increased to 0.83 by combining the criterion of the bowing of the flexor retinaculum measured at grasp position. Although the diagnostic accuracy of MRI is slightly better than that of sonography, sonography can be used as a primary screening method for CTS.
The third study investigated the effectiveness of tendon and nerve gliding exercises as part of combined treatments for CTS. A total of 60 patients were randomized into three groups, and among them 53 were successfully followed after two months of treatments. Every patient received a package of questionnaire, physical examination and NCS of the upper extremity. All patients received conventional treatments (splint and paraffin therapy, as in Group III), but Group I underwent additional tendon gliding exercises, and Group II underwent additional nerve gliding exercises. The results revealed only Group I showed significant improvements in their functional status scores, the DASH questionnaire, and the physical domain of the World Health Organization Quality of Life Questionnaire-Brief Version (WHOQOL-BREF). After adjusting for the baseline data, we found significant differences in the functional status scores among the groups. Post-hoc analyses detected a significant difference in functional status scores between Groups I and II. The combination of tendon gliding exercises with conventional treatments may be more effective than that of nerve gliding exercises with conventional treatments.
In the fourth study, we evaluated the ergonomic and anthropometric risk factors for the female patients with CTS. There were 45 female patients with CTS and 40 healthy volunteers were consecutively recruited. Every participant was enquired about ergonomic risk factors, and received physical examinations, NCS, and MRI study. The results revealed significant differences in patient reported outcomes, results of ergonomic risk factors, physical examinations, NCS, and MRI between the patients and healthy volunteers. Generalized estimating equation revealed significant associations of the occurrence of CTS with the ratio of cross sectional area of median nerve to carpal tunnel with CTS disease status (OR 1.90, 95% CI 1.40-2.57), normalized peak force (OR 1.50, 95% CI 1.21-1.87) and ergonomic index (OR 1.86, 95% CI 1.30-2.64) after adjustment for age and body mass index. Based on these results, it was clear that normalized peak force, ergonomic index and ratio of median nerve to carpal tunnel area were significantly associated with CTS in female patients. Since most of the patients were housewives, further studies to evaluate the relationship between quantified house chores activities and CTS were suggested.

並列關鍵字

occupational carpal tunnel syndrome ； Michigan Hand Outcomes Questionnaire (MHQ) ； Disabilities of the Arm, Shoulder and Hand (DASH) Questionnaire ； tendon gliding exercise ； nerve gliding exercise ； ultrasonography ； magnetic resonance imaging ； ergonomic risk factors

參考文獻

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