Gate Control Theory Research Articles

Quantification of Ureteral Pain Sensation Induced by Kidney Stone

Abstract Pain sensation induced by kidney stone (renal calculi) in ureter, a kind of visceral ducts connecting the kidneys and bladder, critically depends upon the relative size of stone to ureter. To quantify such pain sensation, we draw a parallel analogy between the mechanisms underlying skin pain (which can be quantified with a holistic pain model consisting of a modified Hodgkin–Huxley model and gate control theory) and mechanism of ureteral pain to extend the holistic pain model to the stone-blocked ureter. We then perform finite element simulations to obtain key mechanical stresses on the ureter wall exerted by a kidney stone having varying sizes. These stresses are subsequently adopted to calculate the voltage potential of neuron membrane in the holistic pain model and eventually a theoretical framework to quantify the dependence of ureteral pain sensation on stone size is established, for the first time. We demonstrate that ureter pain sensation increases sharply when the diameter of the kidney stone becomes 7.5% to 20% larger than the inner diameter of ureter, peaking at ∼20% larger; however, increasing further the stone diameter leads only to marginally exacerbated pain sensation. Other related effects on ureter pain sensation, such as ureter wall thickness, ureter stiffness, and intra-abdominal pressure (IAP), are evaluated. The results of the present study provide insightful information for urologists to diagnose and treat patients with renal calculi in a more personalized way.

Treatment of Knee Osteoarthritis with Transcutaneous Electrical Nerve Stimulation

In China, the majority of osteoarthritis patients have the disease in the knee. Clinically, knee osteoarthritis (KOA) often has joint swelling, pain, stiffness, dysfunction and other symptoms, which reduce the patients’ quality of life. There is a trend that osteoarthritis affects more and more young people in China, so it is much more important to treat KOA. Being a cheap and non-surgical option, the transcutaneous electrical nerve stimulation (TENS) has unique advantages in dealing with the pain caused by KOA. This article presents the pathogenesis and pain mechanism of KOA, describes the mechanism of TENS in KOA treatment, discusses the advantages and disadvantages, and proposes some combined treatment methods. Some studies have shown that the pathogenesis of KOA is related to the theory of unequal settlement of knee joints, and the pain comes from cartilage, subchondral bone and synovial membrane lesions. The gate control theory, endogenous opioid peptide release theory and diffuse noxious inhibitory controls theory are considered as the theoretical basis for TENS to inhibit pain. Its effectiveness, adaptability and incidence of adverse reactions are better than using drugs, but it cannot improve walking ability and the range of motion of the joints. Combination therapies of TENS are currently effective for treating KOA, including TENS combined with ultrasound, sodium hyaluronate, massage, functional training and other treatment options.

Modalities of Neuromodulation for Neurological Diseases

Neurological diseases have attracted much attention as they have become the second leading cause of death worldwide. Several works on neuromodulation were reported to improve patients' quality of life or the body's functionality. After the early discovery of the gating theory, electrical stimulation was used to relieve chronic pain. In recent years, several other neuromodulation techniques, including thermal, and pharmacological stimulation, were proposed to improve the effectiveness. In this paper, some of the related researches on electrical, thermal, and pharmacological stimulation are summarized. Scientists are searching for more suitable therapies for neuromodulation now, including improving probe and electrode materials based on existing protocols. In terms of thermal stimulation, light-induced heating of heat conversion materials are introduced. The three administration routes of oral, intravenous and micropump in pharmacological are also mentioned. It also highlight the researches that combine some new cutting-edge technologies (e.g. nanotechnology) with the neuromodulation technique. In the end, the advantages and disadvantages are discussed, and the prospects are forecasted.

Transnasal endoscopy-guided percutaneous access to the sphenopalatine ganglion for neurostimulation in the treatment of primary headache: operative technique and feasibility.

Cluster headache is considered a trigeminal autonomic cephalalgia and may present with characteristic symptoms of sympathetic/parasympathetic activation on the affected side of the face, such as nasal discharge, tearing, and conjunctival injection. Invasive therapies targeting the sphenopalatine ganglion have been performed in these headache syndromes and can have a medication-sparing effect, especially in refractory, difficult-to-manage cases. The gate control theory of pain suggests that electric pulses delivered to nerve tissues can modulate neuronal activity, thus aiding in management of nociceptive or neuropathic pain, and studies have demonstrated the efficacy and safety of sphenopalatine ganglion neurostimulation. Within this context, we sought to assess the feasibility of a new surgical technique for neurostimulation of the sphenopalatine ganglion in a cadaver dissection model. The technique was developed through dissection of two cadaver heads. We divided the procedure into two stages: an endonasal endoscopic approach to expose the sphenopalatine ganglion and confirm electrode placement, and a cervicofacial approach to introduce the electrode array and position the internal pulse-generator unit. Computed tomography was performed to confirm implant placement at the end of the procedure. The pulse-generator unit was successfully placed through a retroauricular incision, as is already standard for cochlear implant placement. This should reduce the incidence of perioperative sequelae, especially pain and swelling in the oral region, which are a common complication of previous approaches used for this purpose. Control imaging confirmed proper electrode placement. The device used in this study allows the patient to modulate the intensity of the stimulus, reducing or even obviating the need for drug therapy. The novel technique described herein, based on percutaneous access guided by transmaxillary endoscopy, can provide great precision in electrode array positioning and decreased perioperative morbidity, combining the advantages of endoscopic approaches with those of the retroauricular route.

Mechanism of Action of Peripheral Nerve Stimulation for Chronic Pain: A Narrative Review.

The use of stimulation of peripheral nerves to test or treat various medical disorders has been prevalent for a long time. Over the last few years, there has been growing evidence for the use of peripheral nerve stimulation (PNS) for treating a myriad of chronic pain conditions such as limb mononeuropathies, nerve entrapments, peripheral nerve injuries, phantom limb pain, complex regional pain syndrome, back pain, and even fibromyalgia. The ease of placement of a minimally invasive electrode via percutaneous approach in the close vicinity of the nerve and the ability to target various nerves have led to its widespread use and compliance. While most of the mechanism behind its role in neuromodulation is largely unknown, the gate control theory proposed by Melzack and Wall in the 1960s has been the mainstay for understanding its mechanism of action. In this review article, the authors performed a literature review to discuss the mechanism of action of PNS and discuss its safety and usefulness in treating chronic pain. The authors also discuss current PNS devices available in the market today.

Assessing the Effectiveness of Helfer Skin Tap Technique on Pain Reduction among Children Undergoing Intramuscular Vaccination in FLACC Numerical Pain Scale

Introduction: Intra muscular vaccination is complex technique used to deliver vaccines among children deep into the large muscles of the body. Pain at injection site is one of the most commonly-reported local reactions associated with administration of a vaccine. It is more painful when combination of more than two vaccines injected at a time among children. Pain management in invasive procedure is a challenge to the nurse. Hence, complementary therapy like Helfer skin tap technique has its own significance and provides a mechanical stimulation and distraction during intramuscular vaccination and thus helps to decrease pain as described by gate control theory which keeps the muscles relaxed while administering IM injection. Objective: A study to assess the effectiveness of Helfer skin taps technique on pain reduction among children undergoing intramuscular vaccination at district hospital Waidhan, Singrauli. Method: The study involved quasi experimental posttest only design with non-probability purposive sampling method. The data was collected from 60 Children’s undergoing intramuscular vaccination. Intervention: In Helfer skin tap technique Intramuscular vaccination is done by tapping to the injection site by using palmer aspect of the hand about three times and inserting the needle without the feeling of pain and removing the needle by tapping the area again three times. Tools: Standardized FLACC 0-10 numerical pain scale used to assess the pain reduction among children undergoing intramuscular vaccination. Results: The data collected was analyzed using descriptive and inferential statistics. The study shows using standard technique in control group 27 children had moderate pain (90%), 3 children had severe pain (10%) while in experimental group 17 had moderate pain (57%), 8 had severe pain (26%) and 5 had mild pain (17%). Analysis among experimental group by using paired‘t’ test found significant value 5.94 at p<0.05 level. The study shows that after the procedure observation intramuscular vaccination is less painful in experimental group as compare to control group among children. Interpretation & Conclusion: The study shows that Helfer skin tap technique was more effective on pain reduction undergoing intramuscular vaccination than the usual standard technique used among children.

Primary Afferent Depolarization and the Gate Control Theory of Pain: A Tutorial Simulation.

The gate control theory of pain postulates that the sensation of pain can be reduced or blocked by closing a "gate" at the earliest synaptic level in the spinal cord, where nociceptive (pain) afferents excite the ascending interneurons that transmit the signal to the brain. Furthermore, the gate can be induced to close by stimulating touch afferents with receptive fields in the same general area as the trauma that is generating the pain (the "rub it to make it better" effect). A considerable volume of research has substantiated the theory and shown that a key mechanism mediating the gate is pre-synaptic inhibition, and that this inhibition is generated by depolarizing IPSPs in the nociceptor central terminals (primary afferent depolarization; PAD). Both pre-synaptic inhibition and depolarizing IPSPs are topics that students often regard as matters of secondary importance (if they are aware of them at all), and yet they are crucial to a matter of primary importance to us all - pain control. This report describes some simple computer simulations that illustrate pre-synaptic inhibition and explore the importance of the depolarizing aspect of the IPSPs. These concepts are then built into a model of the gate control of pain itself. Finally, the simulations show how a small change in chloride homeostasis can generate the dorsal root reflex, in which nociceptor afferents generate antidromic spikes which may increase neurogenic inflammation and actually exacerbate pain. The hope is that the simulations will increase awareness and understanding of a topic that is important in both basic neuroscience and medical neurology.

High-fidelity single-qubit gates of a strong driven singlet-triplet qubit

Semiconductor quantum dot qubits are one of the most promising candidates for quantum computing. Among them, singlet-triplet qubits have attracted much attention due to their excellent properties of all-electric control and accurate readout. To improve qubit immunity to charge noise, strong driving pulses are usually introduced to make operation as fast as possible. However, the complex dynamics induced by strong driving pulses make the rotating wave approximation inapplicable and hinder the implementation of high-fidelity qubit operation. In this work, we present a method of utilizing simple quadrature pulses to correct errors of high-frequency oscillatory terms induced by strong driving. A scheme to obtain these pulses is proposed based on a full quantization of the system and derivative removal by adiabatic gate (DRAG) theory, as the former clarifies the elementary processes of strong driving effects and enables the latter to find correction pulse shapes. The numerical simulation results show that, a NOT gate with 99.99% fidelity and gate time as short as 2 ns can be achieved with the help of the control pulses of this method, which indicates that the control error brought by strong driving is no longer a limiting factor. In particular, NOT gate fidelity higher than 99.9% is achievable even when the charge noise is at a level of <inline-formula><tex-math id="M2">\begin{document}$ 2\ \mu{\rm{eV}} $\end{document}</tex-math><alternatives><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="20-20230906_M2.jpg"/><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="20-20230906_M2.png"/></alternatives></inline-formula>. Notice that this method can be applied to any resonant-driving single-qubit rotation but not just NOT gates. Therefore, our approach will facilitate qubits to realize fast, high-fidelity single-qubit gates under charge noise.

The effect of heat therapy on pain intensity, duration of labor during first stage among primiparous women and Apgar scores: A systematic review and meta-analysis.

Heat therapy may help in reducing pain during labor as it blocks the receptors of pain, according to gate control theory. This systematic review and meta-analysis study aims to evaluate the effect of heat therapy (HT) systematically and critically on pain intensity, duration of labor during the first stage of labor and Apgar scores. We searched for randomized controlled trials published until October 2020 in PubMed/Medline, EMBASE, ClinicalKey, Ovid Discovery, and other sources. Randomized controlled trials (RCTs) comparing heat therapy with standard treatment were selected. Out of 7625 screened, 10 studies met the inclusion criteria. The results of pooled data have shown that heat therapy was significantly effective in reducing pain intensity in the first stage of labor (standard mean difference, SMD= -1.31; 95% CI: -1.88 - -0.73; p<0.001). Heat therapy had significantly reduced the duration of the first stage of labor (pooled MD= -50.09; 95% CI: -89.70-10.48; p=0.01) and was also superior to the standard therapy group in terms of better Apgar scores at the 5th minute of birth of the newborn (pooled MD= -0.10; 95% CI: -0.19-0.02; p=0.02). Current evidence shows that heat therapy effectively decreases labor pain intensity and shortens the duration of labor in the first stage, and it can be used as nonpharmacological management for labor pain.

Spinal Cord Stimulation in Chronic Low Back Pain Syndrome: Mechanisms of Modulation, Technical Features and Clinical Application.

Chronic low-back pain (CLBP) is a common disease with several negative consequences on the quality of life, work and activity ability and increased costs to the health-care system. When pharmacological, psychological, physical and occupational therapies or surgery fail to reduce CLBP, patients may be a candidate for Spinal Cord Stimulation (SCS). SCS consists of the transcutaneous or surgical implantation of different types of electrodes in the epidural space; electrodes are then connected to an Implanted Pulse Generator (IPG) that generates stimulating currents. Through spinal and supraspinal mechanisms based on the “gate control theory for pain transmission”, SCS reduces symptoms of CLBP in the almost totality of well-selected patients and its effect lasts up to eight years in around 75% of patients. However, the evidence in favor of SCS still remains weak, mainly due to poor trial methodology and design. This narrative review is mainly addressed to those professionals that may encounter patients with CLBP failing conventional treatments. For this reason, we report the mechanisms of pain relief during SCS, the technical features and some clinical considerations about the application of SCS in patients with CLBP.

PO152 / #1019 HOW DOES THE SPINAL CORD STIMULATION TOY WITH THE IDEA OF A PLEASANT EFFECT: A CASE REPORT: E-POSTER VIEWING

The spinal cord stimulation (SCS) is a technique of analgesia which consists in the implantation of an epidural electrode over the dorsal columns at the spinal level of injured dermatomes. This technique is based on the gate control theory highlighted by Wall and Melzack in 1965. However, the gate control theory does not explain completely the neurophysiological mechanisms of the SCS. Indeed, the spinal stimulation can recruit the afferents of peripheral nerves, the afferents towards the supraspinal structures, the local neuronal circuits and the autonomic nervous system (1).

O081 / #805 MECHANISMS OF LOW FREQUENCY SUB PERCEPTION SPINAL CORD STIMULATION: TRACK 1: MECHANISMS OF ACTION, MAPPING AND SPINAL CORD STIMULATION

Spinal cord stimulation (SCS) was developed as a treatment for chronic pain based on the gate-control theory, which posits that activation of large diameter afferent fibers leads to inhibition of dorsal horn (DH) pain projection neurons. Conventional SCS uses low stimulation frequencies (<200 Hz) at amplitudes above sensory threshold to activate dorsal column (DC) axons and inhibit pain. SCS above sensory threshold generates paresthesias that some patients find undesirable, and recent subperception modalities of SCS demonstrated equivalent or superior pain relief without evoking paresthesias.

Dorsal Column Stimulation for the Treatment of Refractory Thoracic Radiculopathy: A Case Report

Between 1996-2016, low back and neck pain expenditures amounted to $134.5 billion according to the Journal of the American Medical Association. Spinal Cord Stimulation (SCS) has been used with success in treatment of radiculopathy, peripheral nerve injury, diabetic neuropathy, failed back surgery syndrome, and complex regional pain syndrome. [1] Initially, low-frequency SCS was used and worked by activating large-diameter Ab fibers in the dorsal column, creating paresthesia stimulation at low frequency (120 Hz), high amplitude, and long duration. This was based on the Gate Control Theory so the low-rate pulsed energy applied at the certain vertebrae of the spine would activate A-beta fibers, which would gate out the nociceptive sensations carried by A-delta and C fibers. Then high-frequency stimulation was used with a frequency of 10,000 Hz, low amplitude, and short duration. This selectively activates inhibitory interneurons in the dorsal horn which suppresses wide dynamic range neurons, which are hyperactive in chronic pain. [2] High frequency stimulation has been found to be superior to low frequency in a RCT with 24 month data showing sustained relief [3].

Skin Pain Sensation Under Mechanical Stimulus: Wind-Up and Ramp-Off

Abstract Researchers have been studying the pain sensation extensively in the past few decades. Quantitative simulation and theoretical modeling of pain sensation based on experimental results are necessary for pain research. Many theories have been proposed to explain the mechanism of pain from molecular, cellular, and neuron network perspectives. But some phenomena in pain sensation are not fully understood, including wind-up and ramp-off. This paper focused on the theoretical model of wind-up and ramp-off phenomena in the pain sensation. With the addition of the transduction model, the generation mechanism of wind-up and ramp-off is better explained. The simulations were carried out to analyze the skin pain sensation under the mechanical stimulus, consisting of four different parts: the mechanical model of skin, transduction, transmission, modulation, and perception. The stress distribution on the skin was obtained based on the elastic theory. And the modified Hodgkin and Huxley model and the mathematical model of gate control theory were utilized to analyze the process of transduction, modulation, and perception, respectively. The numerical experiments demonstrated the wind-up occurs with a frequent stimulus of 1 Hz and 2 Hz, and ramp-off appears with the withdrawal of constant mechanical stimulus, which could contribute to the understanding of the pain sensation mechanism.

Pain modulation in the spinal cord.

The sensory inflow from the periphery that triggers innocuous and painful sensations is highly complex, capturing key elements of the nature of any stimulus, its location, intensity, and duration, and converting this to dynamic action potential firing across a wide population of afferents. While sensory afferents are highly specialized to detect these features, their input to the spinal cord also triggers active processing and modulation there which determines its output, to drive the sensory percept experienced and behavioral responses. Focus on such active spinal modulation was arguably first introduced by Melzack and Wall in their Spinal Cord Gate Control theory. This theory has had a profound influence on our understanding of pain, and especially its processing, as well as leading directly to the development of clinical interventions, and its historical importance certainly needs to be fully recognized. However, the enormous progress we are making in the understanding of the function of the somatosensory system, means that it is time to incorporate these newly discovered features into a more complex and accurate model of spinal sensory modulation.

Effect of an integrative nursing program on pain of school-age children with leukemia undergoing lumbar punctures

The purpose of this quasi-experimental research was to examine the effect of an integrative nursing program on pain of school-age children with leukemia undergoing lumbar punctures. The Gate Control Theory provided the conceptual framework for this study. The subjects were 30 leukemia children aged between 8-12 years old undergoing lumbar punctures with the pain scores of two or over and being treated with chemotherapy at Khon Kaen Hospital. The first 15 children were allocated based on a simple random sampling of the control group and the last 15 children in the experimental group. The research instruments of this study were a pain assessment form and an Integrative Nursing Program. Children in the treatment group received integrative nursing care. The experiment was divided into three periods, namely pre-trial, post-trial, and follow-up periods. The data were analyzed using frequency, percentage, mean, standard deviation, and t-test. The findings of this research revealed that children undergoing the Integrative Nursing Program had significantly less pain than children receiving conventional nursing care at the statistical level of .05. The children received integrative nursing care had significantly less pain in post-trial and follow-up periods than the pre-trial period at the statistical level of .05.

Is spinal cord stimulation useful in the long term? A commentary on Brill et al.

This journal recently published a paper by Brill et al., entitled ‘Short and long term effects of conventional spinal cord stimulation on chronic pain and health perceptions: a longitudinal controlled trial’. In fact, spinal cord stimulation (SCS) is considered a last-option technique to manage chronic refractory neuropathic pain, initially based on the gate control theory with subsequent other documented mechanisms of action. Even though pain relief assessment is highly subjective, objective SCS effects on clinical pain were well-documented years ago using nociceptive flexion reflexes-RIII (Garcia-Larrea et al., 1989), ruling out a possible paresthesia-based placebo effect of the procedure. While short-term pain relief following SCS is well documented, the long-term clinical SCS benefits remain questionable. Moreover, patients may develop tolerance to SCS, with loss of the therapeutic effect over time (Taccola et al., 2020). These issues can be tackled using a control group as a comparison, which is somewhat unethical, and/or a sham group which is unrealistic since conventional SCS induces paresthesiae. Very few studies considered the long-term effects of SCS on a large sample of patients. While the beneficial effect of SCS at 1 year on a large sample was clearly documented (EMP3OWER study, 401 patients; Rosenberg et al., 2016), longer beneficial effects have only been reported in very small series (Kumar et al., 2008). The recently published article in the European Journal of Pain concerns a study on 167 patients candidates for SCS followed for 28 weeks post-implantation (Brill et al., 2022). The authors used the patients whose SCS initial trial failed as a comparison group for the patients permanently implanted with SCS. They found no beneficial effects for the SCS group at the last follow-up compared to either the pre-operative status or the failed trial group. The results of this study are in contrast with those of most published data about the efficacy of SCS, and the strength of this series includes the absence of sponsorship by the devices' manufacturers, the number of patients (n = 167) and the test–retest study for the outcome measures—with clear cut-off values for a clinically significant difference. Notwithstanding these merits, the findings and conclusions of the study are to be interpreted with caution, since the study, although well conducted and interesting, carries limitations the reader must take into consideration. The comparison group used in this study is not typical and can induce bias in the comparison. Patients disappointed by the failure of the “last chance therapy” can either work psychologically on themselves and develop useful coping strategies, can successfully modify their other therapeutic approaches, or use illicit drugs and/or medications to overcome their suffering. Thus, they cannot be considered as a robust comparison group like a placebo/sham group. Of note, outcome measures did not include medication intake in the two groups; reporting this parameter is extremely important since a significant difference between the two groups would be in itself an objective marker of SCS efficacy. A third and important limitation is the absence of multivariate analysis, most probably because of the sample size, in order to investigate the influence of several factors like the device's manufacturer, the aetiology of the chronic pain and also the pain duration. The question that remains unanswered is why the findings of this study are in contradiction with most previously published data in the literature. One explanation might be that some studies exclude analysis of drop-out patients, but the probability that this alone explains the results appears very low. Given the generally good methodology followed in this paper, only the possible biases mentioned above, the patient population/selection process and/or the technique itself appear as potential explanations of the observed divergences with previous literature. In any case, the results are of potential importance and should prompt the development of other studies with a high level of evidence, which take into consideration the challenges of placebo/sham in this context, in order to document the real long-term effectiveness of SCS on pain relief in chronic refractory neuropathic pain.

Mathematical Model for Skin Pain Sensation under Local Distributed Mechanical Compression for Electronic Skin Applications.

Skin pain resulting from mechanical compression is one of the most common pains in daily life and the indispensable information for electronic skin to perceive external signals. The external mechanical stimuli are transduced into impulses and transmitted via nerve fiber, and finally, the sensation is perceived via the procession of the nerve system. However, the mathematical mechanism for pain sensation due to mechanical stimuli remains unclear. In this paper, a mathematical model for skin pain sensation under compression is established, in which the Flament solution, the revised Hodgkin–Huxley model, and the mathematical model gate control theory are considered simultaneously. The proposed model includes three parts: a mechanical model of skin compression, a model of transduction, and a model of modulation and perception. It is demonstrated that the pain sensation degree increases with the compression amplitude and decreases with deeper nociceptor location in the skin. With the help of the proposed model, the quantitative relationship between compression pain sensation and external mechanical stimuli is revealed, which has a significant benefit in promoting the design and mechanism research of electronic skin with pain perception function.

A Rare Case of Anchor Fracture Manifesting With New-Onset Neuropathic Pain After Spinal Cord Stimulator Implantation

A spinal cord stimulator (SCS) delivers electric fields in the epidural space, which is thought to alleviate pain via the gate control theory, wide-dynamic range neuron modulation, and cortical modulation.1 SCS hardware malfunctions outnumber biological complications.2,3 Of hardware complications, lead migration remains the most common ranging from 8.5%–21.0% of cases, followed by lead fracture occurring in 4.3%–10.2% of cases.2

Editorial

Editorial