Caufriez Benoît, Dugailly Pierre-Michel, Brassinne Eric, Schuind Frédéric
* Department of Orthopaedics and Traumatology, Erasme University Hospital, Brussels, Belgium.
J Hand Surg Asian Pac Vol. 2018 Mar;23(1):102-110. doi: 10.1142/S2424835518500145.
In the classical conception, the brachioradialis is a forearm supinator. The hypothesis of this study was that, at least in certain positions of elbow flexion and forearm rotation, the brachioradialis is, along with the biceps and brachialis, one of the main elbow flexors.
Fifteen young healthy male volunteers participated in this research. The activities of the biceps, brachialis and brachioradialis muscles were studied using surface electromyography, while the subjects were performing elbow flexions/extensions with as much strength as possible, forearm in neutral position, then in full pronation, then in full supination. The elbow flexion torques were isokinetically measured at 60°/sec for an arc of 120°.
The biceps, brachialis and brachioradialis muscles were electromyographically very active throughout resisted elbow flexion, in all three investigated positions of forearm rotation. At certain positions, the electromyographic activities were much higher than the maximal voluntary contraction signal. For what concerns specifically the brachioradialis, in all three forearm rotation investigated positions, the activity curve demonstrated a slow increase during the first part of elbow flexion, reaching in 73.3% of subjects its peak at the end of flexion; in the remaining 26.7%, the brachioradialis had a flat activity without significant peak. The activity was slightly higher in supination.
This study indirectly supports the idea that the brachioradialis is one of the main elbow flexors, especially when the elbow flexion is done with the forearm in supination. This observation could be important in clinical elbow and wrist surgical practice.
在传统观念中，肱桡肌是前臂旋后肌。本研究的假设是，至少在肘关节屈曲和前臂旋转的某些位置，肱桡肌与肱二头肌和肱肌一样，是主要的肘关节屈肌之一。
15名年轻健康男性志愿者参与了本研究。在受试者将前臂置于中立位、完全旋前位和完全旋后位，尽可能用力进行肘关节屈伸时，使用表面肌电图研究肱二头肌、肱肌和肱桡肌的活动。以60°/秒的等速测量120°弧度的肘关节屈曲扭矩。
在所有三个研究的前臂旋转位置，在抗阻肘关节屈曲过程中，肱二头肌、肱肌和肱桡肌的肌电图均显示非常活跃。在某些位置，肌电图活动远高于最大自主收缩信号。具体就肱桡肌而言，在所有三个研究的前臂旋转位置，活动曲线在肘关节屈曲的第一阶段缓慢上升，73.3%的受试者在屈曲结束时达到峰值；在其余26.7%的受试者中，肱桡肌活动平稳，无明显峰值。旋后位时活动略高。
本研究间接支持了肱桡肌是主要肘关节屈肌之一的观点，尤其是当前臂处于旋后位进行肘关节屈曲时。这一观察结果在临床肘关节和腕部手术实践中可能具有重要意义。
