Kai Yoshihiro, Gotoh Masafumi, Madokoro Kazuya, Takei Kazuto, Murata Shin, Kanazawa Tomonoshin, Shibata Hideaki, Morihara Toru, Shiba Naoto
Faculty of Health Science, Kyoto Tachibana University, Yamada-cho, Yamashina-ku, Kyoto, Japan.
Department of Orthopedic Surgery, Kurume University Medical Center, Kokubu-machi, Kurume, Fukuoka, Japan.
Asia Pac J Sports Med Arthrosc Rehabil Technol. 2015 Jan 29;2(1):36-41. doi: 10.1016/j.asmart.2014.12.001. eCollection 2015 Jan.
The empty can (EC) and full can (FC) tests are used as diagnostic tools for patients with rotator cuff disease. However, recently concerns have been raised that these tests do not selectively activate the muscle. Therefore, the purpose of this study was to evaluate the rotator cuff muscle activation levels during the EC and FC tests in various positions using electromyography. Twelve healthy, right-handed men without shoulder complaints (mean age: 26.1 years, range: 23-35 years) were included. The tests were performed isometrically with the shoulder elevated at 45° and 90° in the sagittal, scapular, and coronal planes, either in the thumb-up (FC test) or thumb-down (EC test) positions. During these positions, the electromyographic signal was recorded simultaneously from the four shoulder muscles using a combination of surface and intramuscular fine-wire electrodes. The average activation of the supraspinatus and subscapularis was greater during the EC test than during the FC test and in the scapular and coronal planes than in the sagittal plane at 90°. For the infraspinatus, there were no significant differences in any positions between the two tests. Thus, the rotator cuff muscles are influenced by arm position and the elevation plane during the EC and FC tests.
空罐（EC）试验和满罐（FC）试验被用作诊断肩袖疾病患者的工具。然而，最近有人担心这些试验不能选择性地激活肌肉。因此，本研究的目的是使用肌电图评估在不同位置进行EC和FC试验时肩袖肌肉的激活水平。纳入了12名无肩部疾病的健康右利手男性（平均年龄：26.1岁，范围：23 - 35岁）。试验在矢状面、肩胛面和冠状面将肩部抬高45°和90°时进行等长收缩，分别处于拇指向上（FC试验）或拇指向下（EC试验）位置。在这些位置期间，使用表面电极和肌内细丝电极组合同时记录四块肩部肌肉的肌电信号。在EC试验期间，冈上肌和肩胛下肌的平均激活程度高于FC试验，且在肩胛面和冠状面90°时高于矢状面。对于冈下肌，两种试验在任何位置均无显著差异。因此，在EC和FC试验期间，肩袖肌肉受手臂位置和抬高平面的影响。
