下背痛患者彎腰誘發疼痛行為之量化分析

Abstract

研究目的：下背痛是復健科門診最常見的疾病之一。下背痛患者的全面性疼痛評估是非常重要的；因此，臨床醫療與研究專家需要發展出一套客觀和量化地測量下背痛的系統。下背痛患者最常見的疼痛來源為肌肉性疼痛，而動態表面肌電圖正是用於評估下背部肌肉的穩定可靠的工具。動態表面肌電圖中所呈現的特殊彎腰後放鬆現象是辨別下背痛的良好指標。此外，為了表達疼痛，握拳是忍受疼痛時病人常見的疼痛行為，並且易於量化分析。本研究所發展的系統結合了動態表面肌電圖與握力量測，用於定量分析下背痛患者彎腰所誘發的疼痛行為。 方法：本系統包含無線多通道訊號記錄器、無線傳輸模組、表面肌電圖、握力器、桌上電腦。受試者為27位下背痛患者（8位男性，19位女性）。首先記錄視覺疼痛類比量表（VAS），奧氏下背痛失能問卷（ODQ），以及貝氏憂鬱量表（BDI）。實驗過程中，受試者先彎腰後直立，同時必需握著握力器。彎腰過程中，若疼痛強度越強，握力器就握越緊。 結果：本研究受試者平均年齡為45.4±17.2歲；VAS平均分數為 5.37 ± 2.05；ODQ平均分數為30.03 ±17.93 %；BDI 平均分數為9.3 ± 7.1。此結果顯示本研究受試者為中度疼痛，低度失能，而並無憂鬱的下背痛患者。在彎腰測試方面，受試者的握力與表面肌電圖面積的相關係數平均值為0.93。進一步分析表面肌電圖與握力訊號開始的潜期差，男性與女性下背痛患者之間有顯著差異（p<0.05）。男性下背痛患者的握力訊號會較表面肌電圖訊號更慢出現，女性下背痛患者則呈現快慢不一致的潜期。 結論：本研究結果顯示動態表面肌電圖和握力的量測可以用於客觀量化地分析下背痛患者疼痛行為。本研究也顯示男性與女性下背痛患者的疼痛行為有顯著的不同。

Background: Low back pain (LBP) is one of the most common reasons which bring patients to consult a health care professional, especially in a rehabilitation outpatient clinic. A comprehensive pain assessment for LBP patients is very important; researchers and clinicians need to develop a system to record the pain intensity of LBP patients quantitatively and objectively. The most common possible source of pain in LBP patients is muscular pain. For evaluation of muscles over low back, dynamic surface electromyography (SEMG) is a reliable and stable tool. The special flexion-relaxation phenomenon (FRP) in dynamic SEMG is a good indicator of LBP patients. For expression of pain, hand grasp is a common pain behavior when tolerating pain and hand grasp is easy to be analyzed quantitatively. Our research developed a system combining dynamic SEMG and grasp force measurement to analyze the pain behavior induced by bending in low back pain patients quantitatively. Methods: Our system included a wireless multi-channel biomedical signal recording device, wireless transceiver module, SEMG, dynamometer, and a personal computer (PC). 27 LBP patients (8 males and 19 females) were included in this research. We recorded the score of visual analog scale (VAS), Oswestry low back disability questionnaire (ODQ), and Beck depression inventory (BDI) before testing. In SEMG and dynamometer test, subjects grasped the dynamometer and performed a flexion-extension test maneuver. They were instructed to grasp the dynamometer tighter if stronger pain. Results: In basic data, the average age of subjects is 45.4±17.2 years old, the average score of VAS is 5.37 ± 2.05, the average score of ODQ is 30.03 ±17.93 %, and the average score of BDI is 9.3 ± 7.1. These results show that the pain intensity is moderate, the disability level is low, and there is almost no depression in our subjects. In SEMG and dynamometer test, the mean of correlation-coefficient between the grasp force area and the SEMG area is 0.93. The latency difference between gasp force and SEMG is significantly different between male and female LBP patients (p<0.05). Male patients show a slower onset of grasp force than SEMG, but female patients show an inconsistence on latency difference. Conclusions: The measurement of dynamic SEMG and grasp force can be used to analyze the pain behavior objectively and quantitatively in LBP patients. There is obvious difference of pain behavior between male and female LBP patients. Key words: pain behavior, low back pain.