The University of Queensland, NHMRC Centre of Clinical Research Excellence in Spinal Pain, Injury and Health, School of Health and Rehabilitation Sciences, Brisbane, Queensland, Australia.
J Orthop Res. 2012 Feb;30(2):311-8. doi: 10.1002/jor.21499. Epub 2011 Jul 28.
Controversy exists regarding the function of psoas major (PM) and quadratus lumborum (QL) at the lumbar spine. The functions of discrete regions of PM and QL were studied during trunk loading tasks. Twelve healthy participants performed isometric trunk loading tasks in various directions in upright sitting. Fine-wire electromyography (EMG) electrodes were inserted under ultrasound guidance into PM fascicles arising from the transverse process (PM-t) and vertebral body (PM-v) and the anterior (QL-a) and posterior (QL-p) layers of QL on the right side. Although right PM-t and PM-v were both active during right lateral-flexion trunk efforts, their activity was opposite in the sagittal plane, with greater PM-t towards extension and PM-v towards flexion. QL-a and QL-p were similarly active, though QL-p was active to a greater percentage of MVC during right trunk lateral-flexion efforts. Activity of QL-p was modulated with respiratory phase during the loading tasks with trunk efforts towards the right lateral-flexion/flexion and right lateral-flexion directions. These findings provide novel understanding of the unique activation of discrete regions of PM and QL. These differences must be considered in future EMG studies to better understand the function of these deeply situated trunk muscles in the control of the lumbar spine.
对于腰脊柱处的腰大肌（PM）和腰方肌（QL）的功能存在争议。在躯干负荷任务中研究了 PM 和 QL 的离散区域的功能。12 名健康参与者在直立坐姿中以各种方向执行等长躯干负荷任务。在右侧，在超声引导下将细电肌电图（EMG）电极插入从横突（PM-t）和椎体（PM-v）发出的 PM 纤维束以及 QL 的前（QL-a）和后（QL-p）层。虽然右侧 PM-t 和 PM-v 在右侧侧屈躯干用力时均有活性，但它们在矢状面的活性相反，PM-t 朝向伸展，PM-v 朝向屈曲。QL-a 和 QL-p 的活性相似，但在右侧躯干侧屈用力时，QL-p 的活性占 MVC 的百分比更大。在向右侧侧屈/屈曲和右侧侧屈方向的负荷任务中，QL-p 的活动随着呼吸相而变化。这些发现为 PM 和 QL 的离散区域的独特激活提供了新的认识。在未来的 EMG 研究中，必须考虑这些差异，以更好地了解这些深置于躯干肌肉在腰椎控制中的功能。
