Transcutaneous Electrical Nerve Stimulation for the Management of Neuropathic Pain: The Effects of Frequency and Electrode Position on Prevention of Allodynia in a Rat Model of Complex Regional Pain Syndrome Type II

Abstract

Background and Purpose. Complex regional pain syndrome type II (CPSII) is a painful condition that develops following a nerve injury. Although transcutaneous electrical nerve stimulation (TENS) relieves the pain of CPSII, the stimulation parameters that would best prevent the development of the condition are not known. The purpose of this study was to compare the ability of several different stimulation strategies to reduce the development of allodynia. Subjects. Sprague-Dawley rats were used in the study. Methods. A chronic constriction injury (CCI) to the right sciatic nerve was used to induce allodynia. Two groups of CCI rats received high-frequency TENS to the lumbar paravertebral region with electrodes positioned on the skin overlying either the right or left paraspinal musculature. Two additional groups of CCI rats received low-frequency TENS to acupuncture points in the right or left hind limbs. A fifth group of CCI rats received no TENS intervention. Thermal and mechanical pain thresholds were assessed in the right hind paw before and 12 days after the CCI surgery. The TENS was delivered 1 hour per day beginning on the day of surgery. Results. Daily high-frequency TENS reduced the development of mechanical allodynia in CCI rats, and low-frequency TENS reduced the development of thermal allodynia, but only when TENS was delivered on the left side. Discussion and Conclusion. The results indicate that TENS delivered contralateral to a nerve injury best reduces allodynia development. Comprehensive reduction of allodynia development would require a combination of high- and low-frequency TENS intervention.

High‐ and low‐frequency transcutaneous electrical nerve stimulation delay sciatic nerve regeneration after crush lesion in the mouse

“…Also, TENS is usually employed to control neuropathic pain ( Leem et al, 1995; Hanai, 2000; Nam et al, 2001; Cheing and Luk, 2005; Somers and Clemente, 1998; 2003; 2006 ) , which is often associated with peripheral nerve lesions and sometimes WD ( Latinovic et al, 2006 ) . TENS analgesic effects are related to the release of endogenous opioids ( Sluka and Walsh, 2003 ) ; this is related to another controversy on its use to improve nerve regeneration because chronic opioid exposure may be associated with tolerance and inhibition of various steps of the peripheral nerve restoration process ( Smith and Hui, 1973; Sinatra and Ford, 1979; Sinatra et al, 1979; Zeng et al, 2007 ) .…”

Effects of transcutaneous electrical nerve stimulation in patients with peripheral and central neuropathic pain

“…Both high-frequency (hi) and low-frequency (lo) TENS are used to treat neuropathic pain patients. hi teNs affects muscarinic receptors through a µ-opioid receptor-dependent mechanism, and lF TENS treatments alleviate secondary allodynia through serotonergic, muscarinic, and µ-opioid receptor-dependent mechanisms (28,29). Norrbrink (29) investigated the effectiveness of lo and hi TENS in 24 ScI patients, and found that neither current type significantly improved the pain intensity ratings.…”

<p>Remote Analgesic Effects Of Conventional Transcutaneous Electrical Nerve Stimulation: A Scientific And Clinical Review With A Focus On Chronic Pain</p>

“…101 In a later study, these researchers demonstrated that TENS applied contralaterally to the nerve injury reduced the development of allodynia following the nerve-constriction injury. 99 In a third study, they showed that contralateral TENS elevated the inhibitory neurotransmitter GABA bilaterally in the dorsal horn and also reduced mechanical allodynia on the side of the nerve-constriction injury. 100 GABA plays a key role in mediating antinociception in the spinal cord.…”

“…In a series of studies, Somers et al evaluated the physiological and analgesic effects of TENS in rats with a chronic nerve-constriction injury, which is a model for neuropathic pain. [98][99][100] They showed that daily conventional TENS on the same side as the nerve injury reduced bilateral dorsal horn content of aspartate and glutamate compared to untreated rats. 98 These excitatory neurotransmitters play a key role in the development and maintenance of neuropathic pain.…”