Differential Effects of Subcutaneous Electrical Stimulation (SQS) and Transcutaneous Electrical Nerve Stimulation (TENS) in Rodent Models of Chronic Neuropathic or Inflammatory Pain

A Randomized Controlled Trial of Subcutaneous Nerve Stimulation for Back Pain Due to Failed Back Surgery Syndrome: The SubQStim Study

“…Vera‐Portocarrero et al (2013) used rodent models of inflammatory and neuropathic pain to investigate subcutaneous electrical stimulation (SQS) vs. transcutaneous electrical nerve stimulation (TENS) . The rodent model of subcutaneous stimulation was compared to a rodent TENS model, since an argument could be made that SQS is just “TENS under the skin.” When comparing both models, there were differences in the effects of each therapy modality on rodent models of neuropathic pain and inflammatory pain.…”

A Review of Spinal and Peripheral Neuromodulation and Neuroinflammation: Lessons Learned Thus Far and Future Prospects of Biotype Development

“…Subcutaneous electrical stimulation involves the placement of electrodes in the subcutaneous space likely targeting sensory nerve ending branches much like TENS. Vera‐Portocarrero et al demonstrated behavioral hypersensitivity in rats following inflammatory or neuropathic insults and showed some differences between SQS and TENS depending on the nature of the painful stimulus . Specifically, rats exposed to carrageenan and kaolin injection to induce muscle inflammation in response to mechanical painful stimuli demonstrated increasing hypersensitivity over time when treated with TENS, suggesting the development of tolerance.…”

“…The authors hypothesize the difference may relate to the activation of large Aβ fibers in SQS treatment due to deeper anatomic placement compared to the preferential activation of more superficial Aδ fibers in TENS treatment. Opioid‐mediated mechanisms and subsequent tolerance issues are linked to Aδ fibers, whereas non‐opioid mediators are released with Aβ fiber activation . The mechanism underlying differences in treatment efficacy between inflammatory and neuropathic models for both treatment modalities warrant further investigation.…”

“…Dorsal root ganglion (DRG) stimulation represents a targeted approach for selective neuropathic pain conditions of the lower extremities (CRPS type I and II) . In addition, recent studies have predominantly sought to explain the molecular effects when stimulating distal sensory nerve terminals via transcutaneous electrical nerve stimulation (TENS) and electroacupuncture (EA) . However, possible relationships between neurostimulation pain therapies and markers of the neuroimmune axis still remain relatively unexplored in preclinical and clinical trials.…”

Mechanism of Spinal Cord and Peripheral Nerve Stimulation: More than the Gate Control Theory

“…A novel model of SQS has been developed in rodents and this model has proven to mimic some of the aspects of clinical practice. When compared with a rodent model of transcutaneous electrical nerve stimulation (TENS), the SQS model presented with differential effects than the TENS model, suggesting the involvement of different mechanism of action between these two neuromodulation therapies [5]. Future studies will concentrate in investigating optimal parameters of stimulation with the SQS model.…”