Department of Physiotherapy, Tuen Mun Hospital, Hong Kong, China.
Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hong Kong, China.
Int J Environ Res Public Health. 2018 May 16;15(5):1001. doi: 10.3390/ijerph15051001.
This study examined the changes in spinal kinematics and muscle recruitment of the lumbopelvic region associated with prolonged squatting. Eight subjects with chronic nonspecific low back pain (LBP) and eight asymptomatic subjects (AS) performed squat-to-stand and reverse movements, before and immediately after 15 min deep-squatting. Within-group and between-group differences in lumbopelvic kinematics and electromyographic activity acquired in lumbar erector spinae (ES), gluteus maximus (GM), and vastus lateralis (VL) were analyzed. During squat-to-stand after squatting, the LBP group showed slower then faster lumbar movement in the second and third quartiles, respectively. In the second quartile, the AS group moved with a significantly greater lumbar angle. However, significantly greater bilateral GM activity (+4⁻4.5%) was found in the LBP group only. A more profound decrease in bilateral ES activity (-10%) was also shown in the LBP group, yet this was nonsignificant compared to the AS group (-4%). In the third quartile, only the LBP group moved with a significantly greater lumbar angle, together with a significant increase in bilateral ES (+6⁻8%) and GM muscle (+2⁻3%) activity. The findings of the altered pattern of joint kinematics and recruitment of the key lumbopelvic muscles displayed in the LBP group inform on the possible mechanisms that may contribute to the increased risk of developing lumbar dysfunctions for people who work in prolonged squatting postures.
本研究考察了与长时间深蹲相关的腰骶区运动学变化和肌肉募集情况。8 名慢性非特异性下腰痛（LBP）患者和 8 名无症状受试者（AS）分别在深蹲前和深蹲 15 分钟后进行深蹲到站起和反向运动。分析了腰骶区运动学和竖脊肌（ES）、臀大肌（GM）和股外侧肌（VL）的肌电图活动在组内和组间的差异。在深蹲后站立过程中，LBP 组在第二和第三四分位时分别表现出较慢和较快的腰椎运动。在第二四分位时，AS 组的腰椎角度移动明显更大。然而，只有 LBP 组的双侧 GM 活动显著增加（+4⁻4.5%）。LBP 组双侧 ES 活动也明显下降（-10%），但与 AS 组（-4%）相比无显著差异。在第三四分位时，只有 LBP 组的腰椎角度移动明显更大，同时双侧 ES（+6⁻8%）和 GM 肌肉（+2⁻3%）的活动也显著增加。LBP 组关节运动学模式的改变和关键腰骶部肌肉募集的发现，为可能导致从事长时间深蹲姿势工作的人腰椎功能障碍风险增加的机制提供了信息。
