Edmondston Stephen, Björnsdóttir Guðný, Pálsson Thorvaldur, Solgård Hege, Ussing Kasper, Allison Garry
School of Physiotherapy & Curtin Health Innovation Research Institute, Curtin University of Technology, Perth, Western Australia, Australia.
Man Ther. 2011 Aug;16(4):332-8. doi: 10.1016/j.math.2010.12.005. Epub 2011 Jan 20.
Sustained postural loading of the cervical spine during work or recreational tasks may contribute to the development of neck pain. The aim of this study was to compare neck muscle endurance and fatigue characteristics during sub-maximal isometric endurance tests in patients with postural neck pain, with asymptomatic subjects. Thirteen female patients with postural neck pain and 12 asymptomatic female control subjects completed timed sub-maximal muscle endurance tests for the neck flexor and extensor muscles. Muscle fatigue, defined as the time-dependent decrease in median frequency electromyography (EMG), was examined using surface EMG analysis during the tests. The median extensor test holding time was lower but not significantly different in the neck pain group (165 s) that the control group (228 s) (p = 0.17). There was no difference between groups in the flexor test holding time (neck pain = 36 s, controls = 38 s) (p = 0.96). The neck pain group was characterised by greater variability in neck flexor (p = 0.03) and extensor (p = 0.006) muscle endurance. For both tests, the rate of decrease in median frequency EMG was highly variable within and between groups with no significant difference between groups for the flexor or extensor test (p = 0.05-0.82). Patients with postural neck pain did not have significant impairment of neck muscle endurance or accelerated fatigue compared to control subjects. However, the greater variability in these indices of muscle function may reflect patient-specific changes in muscle function associated with neck pain disorder.
在工作或娱乐活动中，颈椎持续承受姿势负荷可能会导致颈部疼痛。本研究的目的是比较姿势性颈部疼痛患者与无症状受试者在次最大等长耐力测试期间的颈部肌肉耐力和疲劳特征。13名患有姿势性颈部疼痛的女性患者和12名无症状女性对照受试者完成了颈部屈肌和伸肌的定时次最大肌肉耐力测试。在测试过程中，使用表面肌电图分析来检测肌肉疲劳，肌肉疲劳定义为肌电图中位频率随时间的下降。颈部疼痛组的伸肌测试中位保持时间（165秒）低于对照组（228秒），但差异不显著（p = 0.17）。两组之间的屈肌测试保持时间没有差异（颈部疼痛组 = 36秒，对照组 = 38秒）（p = 0.96）。颈部疼痛组的特点是颈部屈肌（p = 0.03）和伸肌（p = 0.006）肌肉耐力的变异性更大。对于两项测试，肌电图中位频率的下降速率在组内和组间都高度可变，屈肌或伸肌测试组间无显著差异（p = 0.05 - 0.82）。与对照受试者相比，姿势性颈部疼痛患者的颈部肌肉耐力没有明显受损，疲劳也没有加速。然而，这些肌肉功能指标的更大变异性可能反映了与颈部疼痛障碍相关的特定于患者的肌肉功能变化。
