Németh G, Kronberg M, Broström L A
Department of Orthopaedics, Karolinska Hospital, Stockholm, Sweden.
J Orthop Res. 1990 Jan;8(1):151-3. doi: 10.1002/jor.1100080120.
Operative treatments for recurrent dislocation of the shoulder usually focus on the subscapularis muscle because it is supposed to contribute to the joint stability. It is of clinical interest to record the EMG from the subscapularis muscle in order to interpret its function. The purpose of the present study was to describe a safe and reliable route to reach the muscle, deeply located between the scapula and the thoracic cage, with fine-wire EMG electrodes. Twenty-four shoulders were investigated in 12 volunteers. A hypodermic needle containing bipolar fine-wire electrodes was inserted in the posterior axillary line with the subjects in the supine position, and the arm held in an abducted and externally rotated position. Three criteria confirmed the location of the electrodes: experience of periosteal pain when the needle reached the costal surface of the scapula, drawing-in of the wires 3-4 cm when the subject adducted his arm, thereby rotating his scapula downward, and raw EMG recorded during typical movements. Additionally, in four shoulders, the electrode location was checked with computed tomography. There were no complications from this technique, and the subjects felt no pain from the fine-wire electrodes during arm movements. We conclude that the described technique is a safe and reliable method of reaching the subscapularis muscle with EMG electrodes.
肩关节复发性脱位的手术治疗通常聚焦于肩胛下肌，因为它被认为对关节稳定性有作用。记录肩胛下肌的肌电图以解读其功能具有临床意义。本研究的目的是描述一种使用细丝肌电图电极到达位于肩胛骨和胸廓之间深部的该肌肉的安全可靠途径。在12名志愿者中对24个肩部进行了研究。让受试者仰卧，手臂外展并外旋，将一根装有双极细丝电极的皮下注射针插入腋后线。通过三个标准来确定电极位置：当针到达肩胛骨肋面时的骨膜疼痛体验；受试者内收手臂从而使肩胛骨向下旋转时，电极丝被拉入3 - 4厘米；在典型运动过程中记录到原始肌电图。此外，在四个肩部中，通过计算机断层扫描检查电极位置。该技术没有并发症，并且受试者在手臂运动过程中未感觉到细丝电极带来的疼痛。我们得出结论，所描述的技术是一种使用肌电图电极到达肩胛下肌的安全可靠方法。
