Harnessing the power of gate control: interventions for procedural pain and anxiety

Medical and dental procedures present a minefield of opportunities for pain and anxiety. Many procedures for diagnosis, treatment, and palliation are performed either without comfort measures at all or with sedation/anesthesia. Yet, there are many ways of decreasing patients’ procedural pain and anxiety and of increasing physical and psychological comfort. Gate control theory explains how we can close the gate on pain transmission (and minimize opening the gate) through non-pharmacological means. An exploration of several bottom-up and top-down interventions will be discussed including breathing, mindfulness, gradual exposure, non-pain stimuli, distraction, touch, and postoperative communications. Interventions will be illustrated with pictures and short videos in the dental setting.

Application of Theory in Chronic Pain Rehabilitation Research and Clinical Practice

Introduction: Chronic pain has multiple aetiological factors and complexity. Pain theory helps us to guide and organize our thinking to deal with this complexity. The objective of this paper is to critically review the most influential theory in pain science history (the gate control theory of pain) and focus on its implications in chronic pain rehabilitation to minimize disability. Methods: In this narrative review, all the published studies that focused upon pain theory were retrieved from Ovoid Medline (from 1946 till present), EMBAS, AMED and PsycINFO data bases. Results: Chronic pain is considered a disease or dysfunction of the nervous system. In chronic pain conditions, hypersensitivity is thought to develop from changes to the physiological top-down control (inhibitory) mechanism of pain modulation according to the pain theory. Pain hypersensitivity manifestation is considered as abnormal central inhibitory control at the gate controlling mechanism. On the other hand, pain hypersensitivity is a prognostic factor in pain rehabilitation. It is clinically important to detect and manage hypersensitivity responses and their mechanisms. Conclusion: Since somatosensory perception and integration are recognized as a contributor to the pain perception under the theory, then we can use the model to direct interventions aimed at pain relief. The pain theory should be leveraged to develop and refine measurement tools with clinical utility for detecting and monitoring hypersensitivity linked to chronic pain mechanisms.

Patrick David Wall. 5 April 1925—8 August 2001

Patrick (Pat) Wall was a neurophysiologist and true pioneer in the science of pain. He discovered that the sensory information arising from receptors in our body, such as those for touch and heat, could be modified, or ‘gated’, in the spinal cord by other sensory inputs and also by information descending from the brain; this meant, as is now well recognized, that the final sensory experience is not necessarily predictable from the original pain-eliciting sensory input. He used this to explain the poor relationship between injury and pain, and to illustrate the fallacy of judging what someone ‘should’ be feeling from the sensory input alone. In 1969, together with his colleague, Ron Melzack, Pat proposed the ‘gate control theory of pain’ and the circuit diagram that summarized how central spinal cord circuits can modulate sensory inputs. Later on, he began to regret that ‘goddamned diagram’, which had come to dominate his life and work, but, like all great models, it paved the way for the future. Now, over 50 years after it was first published, molecular genetic dissection of dorsal horn neuronal circuitry has indisputably confirmed that sensory inputs are indeed ‘gated’ in the spinal cord dorsal horn. Through a career that started with a medical degree in Oxford, followed by almost 20 years at Yale and MIT in the USA, and continued at University College London, Pat Wall was a highly influential, critical, creative and original thinker who revolutionized our understanding of the relationship between injury and pain, and who also became a champion for all who suffered from chronic pain.

Effects of Acute and Chronic Stretching on Pain Control

ABSTRACT While muscle stretching has been commonly used to alleviate pain, reports of its effectiveness are conflicting. The objective of this review is to investigate the acute and chronic effects of stretching on pain, including delayed onset muscle soreness. The few studies implementing acute stretching protocols have reported small to large magnitude decreases in quadriceps and anterior knee pain as well as reductions in headache pain. Chronic stretching programs have demonstrated more consistent reductions in pain from a wide variety of joints and muscles, which has been ascribed to an increased sensory (pain) tolerance. Other mechanisms underlying acute and chronic pain reduction have been proposed to be related to gate control theory, diffuse noxious inhibitory control, myofascial meridians, and reflex-induced increases in parasympathetic nervous activity. By contrast, the acute effects of stretching on delayed onset muscle soreness are conflicting. Reports of stretch-induced reductions in delayed onset muscle soreness may be attributed to increased pain tolerance or alterations in the muscle's parallel elastic component or extracellular matrix properties providing protection against tissue damage. Further research evaluating the effect of various stretching protocols on different pain modalities is needed to clarify conflicts within the literature.

A COMPARATIVE CLINICAL STUDY ON PATRA PINDA SWEDA AND TRANSCUTANEOUS ELECTRICAL NERVE STIMULATION ON GRIDHRASI WITH SPECIAL REFERENCE TO SCIATICA

Gridhrasi is a Vata Nanatmaja Vyadhi characterized by Ruk (pain), Toda (pricking pain), Stambha (stiffness) and Spandana (frequents twitching). These symptoms initially affect Sphik (buttock) as well as the posterior aspect of Kati (waist) and then gradually radiates to posterior aspects of Uru (thigh), Janu (knee), Jangha (calf) and Pada (foot). It is dominated by pain that affects the Kandara due to morbid Vata Dosha and Kapha Dosha can also be involved in the clinical presentation. Snehana and Swedana are considered as the general line of treatment for Vatavikaras which can be taken as a line of treatment for Gridhrasi. Patra Pinda Sweda being one among Sankara Sweda is Sagni and Snigdha Ruksha type of Sweda. In this medicinal leaves having Vata-Kaphahara, Shothahara and Vedanasthapaka properties are fried in Sahachara Taila and tied into Pottali. Thus, by virtue of its Guna pos- sess the best Snehana and Swedana effect and acts in respective Avasta of the disease Gridhrasi. There are a number of treatments plans available for sciatica. However transcutaneous electrical nerve stimulation (TENS) is a simple, non-invasive analgesic technique that is used extensively in health care settings by physiotherapists for sciatica. The use of conventional transcutaneous electrical nerve stimulation is originally based on the gate control theory of pain and TENS could also raise endorphin levels in the spinal fluid. Methodology: A comparative clinical study was done on forty subjects of both sexes, between the age group of 20-60 years who were randomly assigned into two groups, namely group A where Patra Pinda Sweda was administered to the subjects and group B wheretranscutaneous electrical nerve stimulation was applied to the subjects. After completion of the study, results were assessed using the student 't’ test by comparing the data collected during the study. Result: Comparatively group A proved to be more effective than group B. Group A overall result is 66.73% and Group B overall result is 47.07%. Keywords: Gridhrasi, Physiotherapy, Sahacahara Taila, Snehana, Swedana

Modulation of Glia-Mediated Processes by Spinal Cord Stimulation in Animal Models of Neuropathic Pain

Glial cells play an essential role in maintaining the proper functioning of the nervous system. They are more abundant than neurons in most neural tissues and provide metabolic and catabolic regulation, maintaining the homeostatic balance at the synapse. Chronic pain is generated and sustained by the disruption of glia-mediated processes in the central nervous system resulting in unbalanced neuron–glial interactions. Animal models of neuropathic pain have been used to demonstrate that changes in immune and neuroinflammatory processes occur in the course of pain chronification. Spinal cord stimulation (SCS) is an electrical neuromodulation therapy proven safe and effective for treating intractable chronic pain. Traditional SCS therapies were developed based on the gate control theory of pain and rely on stimulating large Aβ neurons to induce paresthesia in the painful dermatome intended to mask nociceptive input carried out by small sensory neurons. A paradigm shift was introduced with SCS treatments that do not require paresthesia to provide effective pain relief. Efforts to understand the mechanism of action of SCS have considered the role of glial cells and the effect of electrical parameters on neuron–glial interactions. Recent work has provided evidence that SCS affects expression levels of glia-related genes and proteins. This inspired the development of a differential target multiplexed programming (DTMP) approach using electrical signals that can rebalance neuroglial interactions by targeting neurons and glial cells differentially. Our group pioneered the utilization of transcriptomic and proteomic analyses to identify the mechanism of action by which SCS works, emphasizing the DTMP approach. This is an account of evidence demonstrating the effect of SCS on glia-mediated processes using neuropathic pain models, emphasizing studies that rely on the evaluation of large sets of genes and proteins. We show that SCS using a DTMP approach strongly affects the expression of neuron and glia-specific transcriptomes while modulating them toward expression levels of healthy animals. The ability of DTMP to modulate key genes and proteins involved in glia-mediated processes affected by pain toward levels found in uninjured animals demonstrates a shift in the neuron–glial environment promoting analgesia.

Effect of Vibratory Therapy in Decreasing the Vaccination-induced Pain in Infants: Randomized Controlled Study

Background: Different non-medical therapies such as Non-nutritive sucking (NNS), oral sucrose with or without NNS (non-nutritive sucking), wrapping with thin blanket or cloth, kangaroo mother care (KMC), songs as well as multi-sensory stimulation are beneficial in pain reduction among neonates and infants. According to the gate control theory, vibrations applied sat a site on the body block the nociceptive signals via the A???? and C fibers reducing the pain perception. When used along with many other nonpharmacological methods, This technique has been shown to minimize discomfort in pain-inducing treatments such as Intravenous cannulation, vaccines, heel prick, etc. The primary purpose of this study is to analyze vibrational therapy effects on infants pain perception, thereby, providing evidence for a better pain management strategy in vaccination centers. Objective: To determine the efficacy of vibration therapy on pain perception by infants during vaccine administration. Material and Methods: Out of total 90 eligible healthy infants who come for routinely immunization will be given either vibrational therapy (interventional group) or breastfeeding(control therapy) after doing randomization in this randomized controlled trial. The baseline vitals include cardiac rate (HR), respiratory rate (RR), and oxygen (SpO2) will be recorded before, during, and after vaccination during this treatment. Similarly, we will report Visual analog scales (VAS), Neonatal Infant Pain Scale (NIPS), and Wong-Baker FACES Pain Rating Scale, Modified Behavioral Pain Scale (MBPS) after giving the vaccine to the infant. Results: After completion of the study we will come to know the effect of vibratory therapy on pain control. The pain intensity with the help of the NIPS score will get less in the vibratory group than in the control group. The level of distress by using the Color Analogue Scale, MBPS scale, and FLACC scale, during the vaccine-related procedure will get a lower score in the infants who has taken vibratory therapy than the control group. Conclusion: study will probably give us information about vibration therapy, which will be an effective method for managing the pain after vaccination in infants.

Effect of a Vibration System on Pain Reduction during Injection of Dental Anesthesia in Children: A Randomized Clinical Trial

Background. The ‘‘gate control’’ theory suggests pain can be reduced by simultaneous activation of larger diameter nerve fibers using appropriate coldness, warmth, rubbing, pressure, or vibration. This study investigated the efficacy of a device combining cold and vibration, for needle-related procedural pain in children. Methodology. A total of 51 children aged 5–12 years participated in this randomized controlled clinical trial. Half of the children were in the control group and received maxillary buccal infiltration, by injecting 1.8 ml of 2% lidocaine with 1 : 100,000 adrenaline using topical anesthesia 20% benzocaine gel for 15 seconds, while the other half were in the test group and received the same anesthesia using a commercially available external cold and a vibrating device. A face version of Visual Analogue Scale (VAS) was used as a subjective measure to assess the child’s pain experience. The parents were requested to evaluate the child’s ability to tolerate pain using a behavioral/observational pain scale. Sound, Eyes, and Motor (SEM) scale and Faces, Legs, Activity, Cry, and Consolability (FLACC) scale were used to record the child’s pain as perceived by the external evaluator. T-test or Mann–Whitney U-test was used for scale variables, paired sample T-test or Wilcoxon rank t-test was used for before and after data, and chi-square was used for categorical variable, based on the results of normality test. Results. The results showed a statistically significant reduction in pain after the injection for the test group compared with control using VAS scale (mean = 6.68 (1.09) and 8.42 (0.50); p = 0.001 ) and FLACC scale (mean = 5.92 (1.05) and 8.16 (0.54); p = 0.002 ), but not when using SEM scale (mean 3.22 (0.42) and 4.24 (2.74); p = 0.08 ). Conclusions. Combined external cold and vibrating devices can be an effective alternative in reducing experienced pain and fear in children undergoing infiltration dental anesthesia. This study was registered with clinical trial registry of the United States National Institutes of Health (NIH) at ClinicalTrials.gov (NCT03953001).

A REVIEW ON THE MODE OF ACTION OF AGNIKARMA IN KNEE OSTEOARTHRITIS

Osteoarthritis is a joint disorder which commonly affects the weight bearing joints, especially during old age. It is said to be caused due to wear and tear of joints. In the Asian population, Knee Osteoarthritis is the most common. The clinical presentation includes pain, particularly after prolonged activity and weight-bearing, whereas stiffness is experienced after inactivity. Agnikarma is widely practiced as a quick pain-relieving panacea in this condition. Agnikarma, the most powerful parasurgical procedure in Ayurveda, was first explained by Acharya Sushruta. Sushruta mentions the use of Agnikarma in the diseases affecting Sira (vessels), Snayu (ligaments), Sandhi (joints) and Asthi (bones). Sushruta also mentioned Agnikarma as a treatment modality of Sandhigata Vata. Osteoarthritis can be correlated with Sandhigata vata in Ayurveda. Several studies were conducted to analyze the efficacy of Agnikarma in Knee Osteoarthritis which yielded positive results. The actual mechanism of action of Agnikarma in the management of Knee Osteoarthritis is not yet fully understood, though several theories such as that based on gate control theory, vasodilatation theory etc were put forward by researchers to explain the mode of action. The present work analyses the prominent hypotheses that explain the mode of action of Agnikarma in Knee Osteoarthritis and also explores other possible explanations.