Musculoskeletal Disorders Research Laboratory, Bioengineering Division, Department of Orthopedic Surgery, Health Sciences Center, University of Colorado, Denver, 12800 E 19th Ave, RC-1N, Mail Stop 8343, Box 6511, Aurora, CO 80045, USA.
Eur Spine J. 2010 Aug;19(8):1330-9. doi: 10.1007/s00586-010-1371-4. Epub 2010 Mar 25.
Repetitive or overuse disorders of the lumbar spine affect the lives of workers and athletes. We hypothesize that repetitive anterior lumbar flexion-extension under low or high load will result in significantly elevated pro-inflammatory cytokines expression several hours post-activity. High loads will exhibit significantly higher expression than low loads. Lumbar spine of in vivo feline was subjected to cyclic loading at 0.25 Hz for six 10-min periods with 10 min of rest in between. One group was subjected to a low peak load of 20 N, whereas the second group to a high peak load of 60 N. Following a 7-h post-loading rest, the supraspinous ligaments of L-3/4, L-4/5 and L-5/6 and the unstimulated T-10/11 were excised for mRNA analysis and IL-1beta, IL-6, IL-8, TNFalpha and TGFbeta1 pro-inflammatory cytokines expression. Creep (laxity) developed in the lumbar spine during the loading and the subsequent 7 h of rest was calculated. A two-way mixed model ANOVA was used to assess difference in each cytokines expression between the two groups and control. Tukey HSD post hoc analysis delineated specific significant effects. Significance was set at 0.05. Low and high-load groups exhibited development of creep throughout the cyclic loading period and gradual recovery throughout the 7-h rest period. Residual creep of 24.8 and 30.2% were present in the low and high-load groups, respectively, 7-h post-loading. Significant increases in expression of all cytokines measured relative to control were obtained for supraspinous ligaments from both low and high-load magnitudes. IL-6, IL-8 and TGFbeta1 expression in the high-load group were significantly higher relative to the low-load group. Significant increases in cytokines expression indicating tissue inflammation are observed several hours post-repetitive lumbar flexion-extension regardless of the load magnitude applied. Repetitive occupational and athletic activity, regardless of the load applied, may be associated with the potential of developing acute inflammatory conditions that may convert to chronic inflammation if the viscoelastic tissues are further exposed to repetitive activity over long periods. Appropriate rest periods are a relevant preventive measure.
重复性或过度使用腰椎疾病影响工人和运动员的生活。我们假设，在低或高负荷下进行重复性前屈-伸展运动，将导致活动后数小时内促炎细胞因子的表达显著升高。高负荷会表现出比低负荷更高的表达。在体内猫的腰椎进行了六个 10 分钟的周期加载，每个周期之间有 10 分钟的休息。一组受到 20N 的低峰值负荷，而第二组受到 60N 的高峰值负荷。在加载后 7 小时的休息后，L-3/4、L-4/5 和 L-5/6 的棘上韧带和未刺激的 T-10/11 被切除用于 mRNA 分析和 IL-1beta、IL-6、IL-8、TNFalpha 和 TGFbeta1 促炎细胞因子的表达。计算了腰椎在加载过程中以及随后的 7 小时休息期间发生的蠕变（松弛）。采用双向混合模型方差分析来评估两组和对照组之间每种细胞因子表达的差异。Tukey HSD 事后分析确定了特定的显著影响。显著性设置为 0.05。低负荷和高负荷组在整个循环加载期间和整个 7 小时休息期间均出现蠕变发展。加载后 7 小时，低负荷和高负荷组的残余蠕变分别为 24.8%和 30.2%。与对照组相比，来自低负荷和高负荷的棘上韧带中所有测量的细胞因子的表达均显著增加。高负荷组的 IL-6、IL-8 和 TGFbeta1 表达显著高于低负荷组。无论施加的负荷大小如何，在重复进行腰椎前屈-伸展运动数小时后，都会观察到细胞因子表达的显著增加，表明组织炎症。重复性职业和运动活动，无论施加的负荷如何，都可能导致潜在的急性炎症状态，如果粘弹性组织在长时间内进一步暴露于重复活动，可能会转化为慢性炎症。适当的休息时间是一种相关的预防措施。
