Department of Physical Therapy, College of Biomedical Science and Engineering, The Graduate School, Inje University, and Dong Rae Wooridul Hospital, Gyeongsangnam-do, Republic of Korea.
J Physiol Anthropol. 2011;30(5):203-7. doi: 10.2114/jpa2.30.203.
A high prevalence and incidence of neck and shoulder pain is present in the working population, especially sedentary workers. Recent findings have indicated that the flexion-relaxation (FR) ratio in the cervical erector spinae (CES) muscles might be a significant criteria of neuromuscular impairment and function. Additionally, the active cervical range of motion (ROM) is frequently used for discriminating between individuals with pain and those who are asymptomatic. The purpose of the present study was to examine the relationship between the active cervical ROM and the FR ratio in a sample of regular visual display terminal (VDT) workers. In total, 20 asymptomatic male VDT workers were recruited. Active cervical ROM was measured by a cervical ROM (CROM) instrument. Surface electromyography (EMG) was used to collect myoelectrical signals from the CES muscles, and the FR ratio was calculated for statistical analysis. Pearson correlation coefficients were used to quantify the linear relationship between the active cervical ROM and the FR ratio. The values obtained for the FR ratio in the right CES muscles correlated significantly with the active cervical ROM measured in flexion (r=0.73, p<0.01), left lateral flexion (r=0.64, p<0.01), and left rotation (r=0.60, p<0.01). Flexion (r=0.74, p<0.01) and right lateral flexion (r=0.61, p<0.01) positively correlated with the left FR ratio. Extension and right rotation showed either a very weak or no correlation with the mean value of the right and left FR ratio. Our findings suggested that the cervical FR ratio had a positive correlation with cervical movements, and that changes of the activation patterns in CES demonstrated as cervical FR ratio are associated with reduction of the cervical range of motion including flexion and lateral flexion. In addition, muscular dysfunction of the CES could occur in regular computer workers prior to occurrence of pain; this means that the FR ratio could be used to evaluate the potential risk of neck discomfort in computer workers.
在工作人群中，尤其是久坐的工作者，颈部和肩部疼痛的患病率和发病率都很高。最近的研究结果表明，颈椎伸肌（CES）肌肉的屈伸比（FR）可能是神经肌肉功能障碍的重要指标。此外，主动颈椎活动范围（ROM）常用于区分疼痛和无症状个体。本研究旨在探讨一组常规视屏显示终端（VDT）工作者中主动颈椎 ROM 与 FR 比之间的关系。共招募了 20 名无症状的男性 VDT 工人。主动颈椎 ROM 通过颈椎 ROM（CROM）仪器测量。表面肌电图（EMG）用于从 CES 肌肉中收集肌电信号，并计算 FR 比进行统计分析。Pearson 相关系数用于量化主动颈椎 ROM 与 FR 比之间的线性关系。右侧 CES 肌肉的 FR 比值与前屈（r=0.73，p<0.01）、左侧侧屈（r=0.64，p<0.01）和左侧旋转（r=0.60，p<0.01）测量的主动颈椎 ROM 呈显著相关。前屈（r=0.74，p<0.01）和右侧侧屈（r=0.61，p<0.01）与左侧 FR 比值呈正相关。伸展和右侧旋转与右侧和左侧 FR 比值的平均值呈弱相关或无相关性。我们的研究结果表明，颈椎 FR 比值与颈椎运动呈正相关，CES 的激活模式变化表现为颈椎 FR 比值与颈椎活动范围（包括前屈和侧屈）的减少有关。此外，CES 的肌肉功能障碍可能会在常规计算机工作者出现疼痛之前发生；这意味着 FR 比可用于评估计算机工作者颈部不适的潜在风险。
