Multidisciplinary Pain Center, Aichi Medical University, Nagakute, Japan, Department of Rehabilitation, Faculty of Health Sciences, Nihon Fukushi University, Handa, Japan.
Physiol Res. 2020 Nov 16;69(5):861-870. doi: 10.33549/physiolres.934437. Epub 2020 Sep 9.
The effects of exercise on mechanical hyperalgesia, joint contracture, and muscle injury resulting from immobilization are not completely understood. This study aimed to investigate the effects of cyclic stretching on these parameters in a rat model of chronic post-cast pain (CPCP). Seventeen 8-week-old Wistar rats were randomly assigned to (1) control group, (2) immobilization (CPCP) group, or (3) immobilization and stretching exercise (CPCP+STR) group. In the CPCP and CPCP+STR groups, both hindlimbs of each rat were immobilized in full plantar flexion with a plaster cast for a 4-week period. In the CPCP+STR group, cyclic stretching exercise was performed 6 days/week for 2 weeks, beginning immediately after cast removal prior to reloading. Although mechanical hyperalgesia in the plantar skin and calf muscle, ankle joint contracture, and gastrocnemius muscle injury were observed in both immobilized groups, these changes were significantly less severe in the CPCP+STR group than in the CPCP group. These results clearly demonstrate the beneficial effect of cyclic stretching exercises on widespread mechanical hyperalgesia, joint contracture, and muscle injury in a rat model of CPCP.
运动对固定引起的机械性痛觉过敏、关节挛缩和肌肉损伤的影响尚不完全清楚。本研究旨在探讨周期性牵伸对慢性石膏固定后疼痛（chronic post-cast pain，CPCP）大鼠模型中这些参数的影响。17 只 8 周龄 Wistar 大鼠被随机分为（1）对照组、（2）固定组（CPCP 组）或（3）固定和拉伸运动组（CPCP+STR 组）。在 CPCP 和 CPCP+STR 组中，所有大鼠的双侧后肢均以完全跖屈位用石膏固定 4 周。在 CPCP+STR 组中，在去除石膏后立即开始每周 6 天进行周期性牵伸运动，在重新负重前进行 2 周。尽管在固定组中均观察到足底皮肤和小腿肌肉的机械性痛觉过敏、踝关节挛缩和比目鱼肌损伤，但 CPCP+STR 组的这些变化明显比 CPCP 组轻。这些结果清楚地表明周期性牵伸运动对 CPCP 大鼠模型中广泛的机械性痛觉过敏、关节挛缩和肌肉损伤具有有益作用。
