Sluka K A, Bailey K, Bogush J, Olson R, Ricketts A
Physical Therapy Graduate Program, College of Medicine, 2600 Steindler Building, University of Iowa, Iowa, IA 52242, USA Neuroscience Graduate Program, University of Iowa, Iowa, IA, USA.
Pain. 1998 Jul;77(1):97-102. doi: 10.1016/S0304-3959(98)00090-6.
For years, physical therapists have been utilizing a variety of modalities, including transcutaneous electrical nerve stimulation (TENS), in an attempt to manage pain associated with inflammation. However, the data on clinical effectiveness is conflicting and the neurophysiological mechanism of action is not known. The purpose of this study was to investigate the effects of high and low frequency TENS on the secondary hyperalgesia that occurs after joint inflammation. Secondary hyperalgesia is thought to reflect changes in central neurons and is thus a measure of activity of central neurons. This study utilized the kaolin and carrageenan model of knee joint inflammation and measured the effects of TENS treatment on paw withdrawal latency to radiant heat (secondary hyperalgesia), spontaneous pain behaviors and joint circumference. Either high (100 Hz) or low (4 Hz) frequency TENS was applied to the knee joint for 20 min after the development of hyperalgesia. Both high and low frequency TENS resulted in a reversal of the hyperalgesia immediately following treatment. The effects of high frequency TENS lasted through at least 24 h while those of low frequency TENS lasted through 12 h. There was no effect of TENS on spontaneous pain behaviors or joint swelling when compared to controls. Thus, TENS appears to be more effective in reducing referred pain (or secondary hyperalgesia) without affecting guarding or splinting of the affected limb. Thus, clinically, the choice to use TENS may depend on patient symptoms; specifically TENS should be effective in reducing referred or radiating pain.
多年来，物理治疗师一直在使用包括经皮电刺激神经疗法（TENS）在内的多种治疗方式，试图控制与炎症相关的疼痛。然而，关于临床疗效的数据相互矛盾，其神经生理作用机制尚不清楚。本研究的目的是调查高频和低频TENS对关节炎症后发生的继发性痛觉过敏的影响。继发性痛觉过敏被认为反映了中枢神经元的变化，因此是中枢神经元活动的一种度量。本研究采用高岭土和角叉菜胶诱导的膝关节炎症模型，测量TENS治疗对辐射热引起的爪部退缩潜伏期（继发性痛觉过敏）、自发疼痛行为和关节周长的影响。在痛觉过敏出现后，将高频（100Hz）或低频（4Hz）TENS应用于膝关节20分钟。高频和低频TENS在治疗后立即导致痛觉过敏的逆转。高频TENS的效果至少持续24小时，而低频TENS的效果持续12小时。与对照组相比，TENS对自发疼痛行为或关节肿胀没有影响。因此，TENS在减轻牵涉痛（或继发性痛觉过敏）方面似乎更有效，而不会影响患肢的保护性或夹板固定。因此，在临床上，使用TENS的选择可能取决于患者的症状；具体而言，TENS在减轻牵涉痛或放射痛方面应该是有效的。
