Pain mechanisms: A new theory

Computational modeling of dorsal root ganglion stimulation using an Injectrode

Objective.Minimally invasive neuromodulation therapies like the Injectrode, which is composed of a tightly wound polymer-coated Platinum/Iridium microcoil, offer a low-risk approach for administering electrical stimulation to the dorsal root ganglion (DRG). This flexible electrode is aimed to conform to the DRG. The stimulation occurs through a transcutaneous electrical stimulation (TES) patch, which subsequently transmits the stimulation to the Injectrode via a subcutaneous metal collector. However, it is important to note that the effectiveness of stimulation through TES relies on the specific geometrical configurations of the Injectrode-collector-patch system. Hence, there is a need to investigate which design parameters influence the activation of targeted neural structures.Approach.We employed a hybrid computational modeling approach to analyze the impact of Injectrode system design parameters on charge delivery and neural response to stimulation. We constructed multiple finite element method models of DRG stimulation, followed by the implementation of multi-compartment models of DRG neurons. By calculating potential distribution during monopolar stimulation, we simulated neural responses using various parameters based on prior acute experiments. Additionally, we developed a canonical monopolar stimulation and full-scale model of bipolar bilateral L5 DRG stimulation, allowing us to investigate how design parameters like Injectrode size and orientation influenced neural activation thresholds.Main results.Our findings were in accordance with acute experimental measurements and indicate that the minimally invasive Injectrode system predominantly engages large-diameter afferents (Aβ-fibers). These activation thresholds were contingent upon the surface area of the Injectrode. As the charge density decreased due to increasing surface area, there was a corresponding expansion in the stimulation amplitude range before triggering any pain-related mechanoreceptor (Aδ-fibers) activity.Significance.The Injectrode demonstrates potential as a viable technology for minimally invasive stimulation of the DRG. Our findings indicate that utilizing a larger surface area Injectrode enhances the therapeutic margin, effectively distinguishing the desired Aβactivation from the undesired Aδ-fiber activation.

Development of a Modified Bayonet Forceps for Improving Steerability of Paddle Lead Electrodes During Spinal Cord Stimulator Surgery: A Technical Note

BACKGROUND AND OBJECTIVE

Despite recent advancements in spinal cord stimulation (SCS) technology, the surgical instrumentation for placement of SCS paddle leads remains suboptimal. Therefore, we developed a novel instrument to improve the steerability of SCS paddle leads during surgical placement.

METHODS

A review of existing literature was performed to analyze workflow deficiencies in the standard instrumentation of SCS paddle lead placement. After a period of adaptation and iterative feedback with a medical instrument company, a new instrument was developed, tested at benchtop, and successfully incorporated into the surgical routine.

RESULTS

A standard bayonet forceps was modified to include hooked ends and a ribbed surface, providing the surgeon with greater control over the paddle lead. The new instrument also included bilateral metal tubes starting approximately 4 cm proximal from the edge of the forceps. The bilateral metal tubes, through which the SCS paddle lead wires are passed, serve as anchors to keep the wires away from the incision site. In addition, it permitted the paddle lead to assume a bent configuration, reducing its overall size and allowing it to be placed through a smaller incision and laminectomy. The modified bayonet forceps was successfully used intraoperatively for placement of SCS paddle lead electrodes in several surgeries.

CONCLUSION

The proposed modified bayonet forceps increased steerability of the paddle lead, facilitating optimal midline placement. The bent configuration of the device facilitated a more minimally invasive surgical approach. Future studies are needed to validate our single-provider experience and evaluate the impact of this new instrument on operating room efficiency.

Behavioral cancer pain intervention dosing: results of a Sequential Multiple Assignment Randomized Trial

ABSTRACT

Behavioral pain management interventions are efficacious for reducing pain in patients with cancer. However, optimal dosing of behavioral pain interventions for pain reduction is unknown, and this hinders routine clinical use. A Sequential Multiple Assignment Randomized Trial (SMART) was used to evaluate whether varying doses of Pain Coping Skills Training (PCST) and response-based dose adaptation can improve pain management in women with breast cancer. Participants (N = 327) had stage I-IIIC breast cancer and a worst pain score of > 5/10. Pain severity (a priori primary outcome) was assessed before initial randomization (1:1 allocation) to PCST-Full (5 sessions) or PCST-Brief (1 session) and 5 to 8 weeks later. Responders ( > 30% pain reduction) were rerandomized to a maintenance dose or no dose and nonresponders (<30% pain reduction) to an increased or maintenance dose. Pain severity was assessed again 5 to 8 weeks later (assessment 3) and 6 months later (assessment 4). As hypothesized, PCST-Full resulted in greater mean percent pain reduction than PCST-Brief (M [SD] = -28.5% [39.6%] vs M [SD]= -14.8% [71.8%]; P = 0.041). At assessment 3 after second dosing, all intervention sequences evidenced pain reduction from assessment 1 with no differences between sequences. At assessment 4, all sequences evidenced pain reduction from assessment 1 with differences between sequences ( P = 0.027). Participants initially receiving PCST-Full had greater pain reduction at assessment 4 ( P = 0.056). Varying PCST doses led to pain reduction over time. Intervention sequences demonstrating the most durable decreases in pain reduction included PCST-Full. Pain Coping Skills Training with intervention adjustment based on response can produce sustainable pain reduction.

Response to Mechanical Properties and Physiological Challenges of Fascia: Diagnosis and Rehabilitative Therapeutic Intervention for Myofascial System Disorders

Damage to the fascia can cause significant performance deficits in high-performance sports and recreational exercise and may contribute to the development of musculoskeletal disorders and persistent potential pain. The fascia is widely distributed from head to toe, encompassing muscles, bones, blood vessels, nerves, and internal organs and comprising various layers of different depths, indicating the complexity of its pathogenesis. It is a connective tissue composed of irregularly arranged collagen fibers, distinctly different from the regularly arranged collagen fibers found in tendons, ligaments, or periosteum, and mechanical changes in the fascia (stiffness or tension) can produce changes in its connective tissue that can cause pain. While these mechanical changes induce inflammation associated with mechanical loading, they are also affected by biochemical influences such as aging, sex hormones, and obesity. Therefore, this paper will review the current state of knowledge on the molecular level response to the mechanical properties of the fascia and its response to other physiological challenges, including mechanical changes, innervation, injury, and aging; imaging techniques available to study the fascial system; and therapeutic interventions targeting fascial tissue in sports medicine. This article aims to summarize contemporary views.

Novel Treatments for Chronic Ocular Surface Pain

ABSTRACT

Several etiologies can contribute to ocular surface pain including nociceptive, peripheral neuropathic, and central neuropathic mechanisms. Clinical clues can help identify contributors to ocular surface pain in a patient. In individuals whose pain persists despite targeting nociceptive contributors, neuropathic mechanisms should be considered and addressed using oral, topical, and/or adjuvant agents.

Chronic pain concepts of pediatricians: a qualitative survey

Introduction

Chronic pain is a prevalent, yet underrecognized, condition in children and adolescents. A biopsychosocial framework has been widely adopted over the past decades and resulted in a new pain classification in the International Classification of Diseases, 11th revision (ICD-11). Nevertheless, little is known about pediatricians' pain concepts.

Objectives

We explored pain concepts of Swiss pediatricians by means of a qualitative analysis.

Method

A cross-sectional online survey was sent to clinically active Swiss pediatricians registered with the Swiss Society for Pediatrics. A case vignette of a girl with chronic musculoskeletal pain was presented and pediatricians were asked (1) what they think caused the pain, and (2) how they would explain the pain to the patient and their family. Structuring content analysis was applied to describe major themes within the answers.

Results

The following main categories emerged: psychological factors, biological factors, unclear etiology, social context, disorder specific, and multifactorial. Most pediatricians reported the belief that psychological factors explained the pain. However, when explaining the pain to the patient, biological factors were reported most often.

Conclusion

There is a discrepancy between pediatricians' conviction that chronic pain is mostly explained by psychological factors and their exploratory model towards patients that focuses on biological factors. Promoting the biopsychosocial framework of chronic pain is key to ensure timely and effective treatment. The new pain classification in the ICD-11 has the potential to increase the use of the biopsychosocial model.

Comparison of the Effect of EMLA™ Cream and the Valsalva Maneuver on Pain Severity during Vascular Needle Insertion in Hemodialysis Patients: A Controlled, Randomized, Clinical Trial

Background

Pain due to vascular needle insertion has been reported in 40-60% of hemodialysis (HD) patients. Evidence suggests that there is typically no single method for relieving the pain of inserting vascular needles in HD patients. This study aimed to compare the effectiveness of EMLA cream and Valsalva maneuver (VM) on pain severity during vascular needle insertion in HD patients.

Methods

This randomized, controlled, clinical trial was conducted on 90 patients undergoing hemodialysis in the hemodialysis unit of Kowsar Hospital, affiliated with Semnan University of Medical Sciences, in Semnan, Iran. Patients were selected via convenience sampling and were randomly assigned to one of the three groups (EMLA, VM, and control groups). For the patients in the EMLA group, 2.5 g of EMLA cream was applied 60 minutes before the start of dialysis. For patients in the VM group, a maneuver was performed for 16-20 seconds before the needle was inserted. Patients in the control group received only routine care without any additional interventions. The pain severity in the three groups was measured using the visual analog scale (VAS) two minutes after vascular needle insertion.

Results

The results showed that the mean pain severity during cannulation was 2.06 ± 2.19 in the EMLA group, 3.2 ± 30.42 in the VM group, and 6.20 ± 1.49 in the control group, suggesting a significant difference between the groups (P < 0.001). Pairwise comparison of the mean pain severity showed that it differed significantly in the EMLA and VM groups from the control group (P < 0.001), but no significant difference was found between the EMLA and VM groups (P=0.067).

Conclusion

According to the results, EMLA cream was as effective as VM in reducing the pain severity caused by arteriovenous fistula (AVF) cannulation. Therefore, the use of EMLA cream and VM is recommended for reducing the severity of AVF cannulation pain. Trial Registration. Iranian Registry of Clinical Trials, Trial No : IRCT20120109008665N12, registered on 3 June 2020.

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.

Implementation of a biopsychosocial approach into physiotherapists' practice: a review of systematic reviews to map barriers and facilitators and identify specific behavior change techniques

PURPOSE

Our first objective was to map the barriers and facilitators to the implementation of a biopsychosocial approach into physiotherapists' practice within the Theoretical Domains Framework (TDF). Our second objective was to identify the specific behavior change techniques (BCT) that could facilitate this implementation.

MATERIALS AND METHODS

We conducted a review of systematic reviews to identify barriers and facilitators to the use of a biopsychosocial approach by physiotherapists and we mapped them within the TDF domains. We then analyzed these domains using the Theory and Techniques tool (TaTT) to identify the most appropriate BCTs for the implementation of a biopsychosocial approach into physiotherapists' practice.

RESULTS

The barriers and facilitators to the use of a biopsychosocial approach by physiotherapists were mapped to 10 domains of the TDF (Knowledge; skills; professional role; beliefs about capabilities; beliefs about consequences; intentions; memory, attention and decision processes; environmental context; social influences; emotion). The inclusion of these domains within the TaTT resulted in the identification of 33 BCTs that could foster the use of this approach by physiotherapists.

CONCLUSIONS

Investigating the implementation of a biopsychosocial approach into physiotherapists' practice from a behavior change perspective provides new strategies that can contribute to successfully implement this approach.Implications for RehabilitationThe implementation of a biopsychosocial approach into physiotherapists' practice is a complex process which involves behavior changes influenced by several barriers and facilitators.Barriers and facilitators reported by physiotherapists when implementing a biopsychosocial approach can be mapped within 10 domains of the Theoretical Domain Framework.Thirty-three behavior change techniques (e.g., verbal persuasion about capability, problem solving, restructuring the physical environment, etc.) were identified to foster the implementation of a biopsychosocial approach and specifically target barriers and facilitators.By using a behavior change perspective, this study highlights new strategies and avenues that can support current efforts to successfully implement the use of a biopsychosocial approach into physiotherapists' practice.

Effects of Virtual Reality-Based Aerobic Exercise on Perceptions of Pain and Fatigue in Individuals with Spinal Cord Injury

Virtual reality (VR) has become an effective alternative to promote exercise. However, limited studies have investigated the effect of VR on pain and fatigue in individuals with spinal cord injury (SCI). Objective: The purpose of this study was to investigate the effects of using VR during exercise on pain and fatigue in individuals with SCI. This study employed a concurrent nested mixed-methods design. Materials and Methods: Eleven individuals with SCI completed a 6-minute exercise test using arm ergometry with and without VR. Pain and fatigue questionnaire data were collected using Pain Self Efficacy Questionnaire, the Fatigue Severity Scale, and the Fatigue Assessment Scale. Qualitative data were collected after the VR session. Results: Participants experienced less pain and fatigue during VR exercise than during non-VR exercise. Qualitative data were consistent with the questionnaire results. Conclusion: Clinicians should consider the use of VR in reducing pain and fatigue.

The Influence of Adverse Childhood Experiences in Pain Management: Mechanisms, Processes, and Trauma-Informed Care

Adverse childhood experiences (ACEs) increase the likelihood of reduced physical and psychological health in adulthood. Though understanding and psychological management of traumatic experiences is growing, the empirical exploration of ACEs and physical clinical outcomes remains under-represented and under-explored. This topical review aimed to highlight the role of ACEs in the experience of chronic pain, pain management services and clinical decision making by: (1) providing an overview of the relationship between ACEs and chronic pain; (2) identifying biopsychosocial mechanisms through which ACEs may increase risk of persistent pain; (3) highlighting the impact of ACEs on patient adherence and completion of pain management treatment; and (4) providing practical clinical implications for pain management. Review findings demonstrated that in chronic pain, ACEs are associated with increased pain complications, pain catastrophizing and depression and the combination of these factors further heightens the risk of early treatment attrition. The pervasive detrimental impacts of the COVID-19 pandemic on ACEs and their cyclical effects on pain are discussed in the context of psychological decline during long treatment waitlists. The review highlights how people with pain can be further supported in pain services by maintaining trauma-informed practices and acknowledging the impact of ACEs on chronic pain and detrimental health outcomes. Clinicians who are ACE-informed have the potential to minimize the negative influence of ACEs on treatment outcomes, ultimately optimizing the impact of pain management services.

Involvement of Opioid Peptides in the Analgesic Effect of Spinal Cord Stimulation in a Rat Model of Neuropathic Pain

Spinal cord stimulation (SCS)-induced analgesia was characterized, and its underlying mechanisms were examined in a spared nerve injury model of neuropathic pain in rats. The analgesic effect of SCS with moderate mechanical hypersensitivity was increased with increasing stimulation intensity between the 20% and 80% motor thresholds. Various frequencies (2, 15, 50, 100, 10000 Hz, and 2/100 Hz dense-dispersed) of SCS were similarly effective. SCS-induced analgesia was maintained without tolerance within 24 h of continuous stimulation. SCS at 2 Hz significantly increased methionine enkephalin content in the cerebrospinal fluid. The analgesic effect of 2 Hz was abolished by μ or κ opioid receptor antagonist. The effect of 100 Hz was prevented by a κ antagonist, and that of 10 kHz was blocked by any of the μ, δ, or κ receptor antagonists, suggesting that the analgesic effect of SCS at different frequencies is mediated by different endorphins and opioid receptors.

The Use of an FR1 Schedule Operant Approach-Avoidance Paradigm to Measure the Aversiveness of Neuropathic and Inflammatory Pain

Pain is a subjective, private, yet universal phenomenon that depends on a unique combination of sensory, affective, and evaluative characteristics. Although preclinical models have been used to understand much of pain physiology, the inability to communicate with animals limits affective and evaluative feedback and has constrained traditional behavioral methods to adequately represent and study the multidimensional pain experience. Therefore, this study sought to characterize the affective component of pain within a novel operant approach-avoidance paradigm (AAP) to determine which type of pain (inflammatory and neuropathic) may be more aversive. To reveal the possible differences in pain aversiveness within the AAP paradigm, animals received bilateral inflammatory and neuropathic pain conditions and were given the choice to a) forgo appetitive reward by not receiving noxious stimulus of either inflammatory or neuropathic conditions or b) receive noxious stimulus in exchange for an appetitive reward. Although all pain conditions produced significant hypersensitivity, the AAP results revealed there was no preference in the stimulation of a specific paw in the bilateral pain conditions. The finding suggests that despite unique clinical pain characteristics for inflammatory and neuropathic conditions, the lack of observable differences in the pain conditions may not necessarily equate to the overall similarity in aversiveness, but rather that the fixed ratio (FR1) paradigm presentation allowed appetitive reward to be more salient, highlighting the complexities of competing motivational drives of pain and hunger when satiating hunger is always guaranteed. Thus, future studies should seek to further tease apart this relationship with a different schedule and food-controlled methodologies. The development of such preclinical approaches can thoroughly investigate the intricacy of competing drives and likely reveal important information regarding the complexity of pain, enhancing our understanding of pain perception in individuals suffering from comorbid pain states.

Dorsal root ganglion stimulation produces differential effects on action potential propagation across a population of biophysically distinct C-neurons

Dorsal root ganglion stimulation (DRGS) is a neurostimulation therapy used to manage chronic pain that does not respond to conventional therapies. Unfortunately, not all patients receive sufficient pain relief from DRGS, leaving them with few other treatment options. Presently, our understanding of the mechanisms of action of DRGS is incomplete, preventing us from determining why some patients do not receive analgesia from the therapy. One hypothesis suggests that DRGS augments the filtering of action potentials (APs) at the T-junction of nociceptive C-neurons. To test this hypothesis, we utilized a computational modeling approach in which we developed a population of one thousand biophysically distinct C-neuron models which each produced electrophysiological characteristics (e.g., AP height, AP duration) reported in previous experimental studies. We used this population of model C-neurons to study how morphological and electrophysiological characteristics affected the propagation of APs through the T-junction. We found that trains of APs can propagate through the T-junction in the orthodromic direction at a higher frequency than in the antidromic direction due to the decrease in axonal diameter from the peripheral to spinal axon. Including slow outward conductances in the axonal compartments near the T-junction reduced following frequencies to ranges measured experimentally. We next used the population of C-neuron models to investigate how DRGS affected the orthodromic propagation of APs through the T-junction. Our data suggest that suprathreshold DRGS augmented the filtering of APs at the T-junction of some model C-neurons while increasing the activity of other model C-neurons. However, the stimulus pulse amplitudes required to induce activity in C-neurons (i.e., several mA) fell outside the range of stimulation pulse amplitudes used clinically (i.e., typically ≤1 mA). Furthermore, our data suggest that somatic GABA currents activated directly or indirectly by the DRGS pulse may produce diverse effects on orthodromic AP propagation in C-neurons. These data suggest DRGS may produce differential effects across a population of C-neurons and indicate that understanding how inherent biological variability affects a neuron's response to therapeutic electrical stimulation may be helpful in understanding its mechanisms of action.

Effectiveness of Focused Shockwave Therapy versus Radial Shockwave Therapy for Noncalcific Rotator Cuff Tendinopathies: A Randomized Clinical Trial

Background

The superiority of focused shockwave therapy (F-SWT) versus radial shockwave therapy (R-SWT) for treating noncalcific rotator cuff tendinopathies remains controversial. This study is aimed at comparing the effectiveness of F-SWT versus R-SWT for the management of noncalcific rotator cuff tendinopathies.

Methods

A total of 46 patients affected by noncalcific rotator cuff tendinopathies were randomly divided into 2 groups of 23 individuals. Patients in group A received 4 sessions of F-SWT, while patients in group B were treated by 4 sessions of R-SWT. In each session, mean energy flux density (EFD) for F-SW 3000 shots was 0.09 ± 0.018 mJ/mm² with 5.1 ± 0.5 Hz, while average pressure for R-SW 3000 shots was 4.0 ± 0.35 bar with 3.2 ± 0.0 Hz. Pain level and shoulder function were assessed with the numerical rating scale (NRS) and Constant-Murley Scale (CMS). The primary endpoint was the change in the mean NRS pain score from baseline to 24 weeks after the intervention. Secondary endpoints were changes in the mean NRS pain scores at all other follow-up points, changes in the mean CMS scores, and radiographic findings.

Results

There were no significant differences between the two groups regarding NRS pain score and CMS score within 24 weeks after intervention (all p > 0.05). However, F-SWT resulted in significantly lower NRS compared with R-SWT at 24 weeks and 48 weeks after treatment (2.7 ± 1.0 vs. 4.5 ± 1.2 and 1.4 ± 1.0 vs. 3.0 ± 0.8, respectively, all p < 0.001). Similar results were found in CMS changes and radiographic findings.

Conclusions

Both F-SWT and R-SWT are effective in patients with noncalcific rotator cuff tendinopathy. F-SWT proved to be significantly superior to R-SWT at long-term follow-up (more than 24 weeks). This trial is registered with ChiCTR1900022932.

Effects of electrical stimulation on skin surface

ABSTRACT

Skin is the largest organ in the body, and directly contact with the external environment. Articles on the role of micro-current and skin have emerged in recent years. The function of micro-current is various, including introducing various drugs into the skin locally or throughout the body, stimulating skin wounds healing through various currents, suppressing pain caused by various diseases, and promoting blood circulation for postoperative muscle rehabilitation, etc. This article reviews these efforts. Compared with various physical and chemical medical therapies, micro-current stimulation provides a relatively safe, non-invasive therapy with few side effects, giving modern medicine a more suitable treatment option. At the same time, the cost of the electrical stimulation generating device is relatively low, which makes it have wider space to and more clinical application value. The current micro-current stimulation technology has become more and more mature, but there are still many problems in its research. The design of the experiment and the selection of the current parameters not standardized and rigorous. Now, clear regulations are needed to regulate this field. Micro-current skin therapy has become a robust, reliable, and well-structured system.

Design and Implementation of an Intelligent Analgesic Bracelet Based on Wrist-ankle Acupuncture

A flexible, multifunctional, and intelligent analgesic bracelet was proposed in this article to alleviate symptoms of pain. Based on the theory of wrist-ankle acupuncture in traditional Chinese medicine, transcutaneous electrical nerve stimulation is the technical basis of the method. A set of targeted circuit system capable of generating adjustable electrical stimulation signals to simulate filamentary acupuncture was designed. The system architecture includes a wireless communication module, a signal control module, a stimulus signal generation module, and a wearable, flexible bracelet. In addition, a pain assessment interface with a visual analog scale was designed to assess pain levels. Two comparative experiments were designed, involving a custom pain assessment scale and hand-held dolorimeter that were performed before and after wearing the bracelet to verify the analgesic effect of the bracelet. The results showed that the wrist-worn analgesic bracelet is significantly effective in alleviating pain in various parts of the human body.

Talking to Children and Families about Chronic Pain: The Importance of Pain Education-An Introduction for Pediatricians and Other Health Care Providers

Chronic pain in children and adolescents is a common and debilitating health problem. This narrative review will give a brief overview on what pediatric chronic pain is and what treatment options there are for children and adolescents. The specific emphasis will be on pediatric chronic pain education and communication: this narrative review aims to show how important a good patient-health care provider relationship is-it builds the foundation for successful communication-and how this relationship can be established. In addition, we will present five steps that health care providers can perform to explain pediatric chronic pain to patients and their parents and what to keep in mind in their clinical routine. Our review is intended for pediatricians and other health care providers who treat pediatric patients with chronic pain but might feel uncertain on how to best communicate with them.

Effect of Adding Neural Mobilization Versus Myofascial Release to Stabilization Exercises after Lumbar Spine Fusion: A Randomized Controlled Trial

OBJECTIVES

To test the effect of adding neural mobilization (NM) versus myofascial release (MFR) to stabilization exercises (SE) on disability, pain, and lumbar range of motion (ROM) in patients with lumbar spine fusion (LSF).

DESIGN

A single blinded, parallel groups, randomized controlled trial.

SETTING

Outpatient public and governmental hospital clinics.

PARTICIPANTS

Patients (N=60) who had undergone LSF were randomly assigned into 3 equal groups.

INTERVENTION

Group I received NM plus SE, group II received MFR and SE, and group III received SE only. Each group visited the hospital 3 times a week for 4 weeks.

MAIN OUTCOME MEASURES

Oswestry disability index (ODI), visual analog scale, and back range of motion (BROM) were assessed before starting treatment, immediately after finishing treatment, and 1 month later.

RESULTS

There were statistically significant differences among the groups regarding the ODI and pain (P<.05) in favor of the study groups, but no statistically significant differences were found among groups regarding the BROM outcome (P>.05). Regarding the within-group effect, statistically significant differences were found in all outcomes after 1 month of treatment, as well as after 1 month of follow-up in each group (P<.05).

CONCLUSIONS

Patients who received NM or MFR combined with SE demonstrated better improvement, in favor of the NM group, regarding disability and pain than patients who received SE alone after LSF. No differences were found among the groups regarding lumbar ROM.

The role and outcomes of music listening for women in childbirth: An integrative review

AIM

To synthesise primary research on the role and use of music listening for women in childbirth.

DESIGN

Integrative review.

METHODS

Whittemore and Knafl's (2005) five-stage integrative review method was utilized to complete a systematic search of the literature. Studies were included if they were (a) peer-reviewed, (b) written in the English language, (c) published between 1 January 1979 and 5 April 2019 and (d) described the use of music listening during labour and birth. Studies were appraised for quality and methodological rigor using standardised assessment tools including the Critical Appraisal Skills Programmes (CASP) checklist for the qualitative studies and the Joanna Briggs Institute Critical Appraisal Tool for the quasi-experimental studies and randomised control trials. Data extrapolation, methodological quality assessment and Thematic Content Analysis (Braun and Clarke, 2006) were carried out.

FINDINGS

A total of 931 articles were retrieved and 24 papers were included in the review (12 randomized controlled trials, 9 quasi-experimental and 3 qualitative). The quality of the studies was moderately good overall. Two overarching themes emerged including 'outcomes of using music in childbirth' and, 'music application during childbirth'. Within 'outcomes of using music in childbirth' four subthemes are described: 'pain', 'anxiety', 'psychological supports' and 'progression of labour'. Within 'music application during childbirth' four themes are presented: 'timing of the music application', 'type of music', 'birth preparation using music' and 'mode of music listening'.

CONCLUSION AND IMPLICATIONS FOR PRACTICE

The findings indicate that music listening has a significant role to play for women in childbirth. This non-pharmacological intervention can reduce pain and anxiety while offering a multifaceted form of psychological support to alleviate stress and promote an increased sense of control in women during labour. However, further awareness is needed around the idiosyncratic nature of the music listening experience.

Effectiveness of spa therapy for patients with chronic low back pain: An updated systematic review and meta-analysis

BACKGROUND

Low back pain (LBP) is a major health problem around the world. Two previous meta-analyses showed that the spa therapy has a positive effect on reducing pain among patients with LBP based on studies published before 2006 and studies published between 2006 and 2013. In recent years, more studies reported the effect of spa therapy on treating chronic low back pain (CLBP). Our study aimed to update the meta-analysis of randomized controlled trials (RCTs) about the effect of spa therapy on treating CLBP and to examine the effect of spa therapy based on different interventions.

METHODS

PubMed, Embase, Web of Science, and Cochrane Library were searched until May 2018 to identify RCTs about spa therapy among patients with CLBP. Summary effect estimates were calculated by using a random-effects model. The quality of each eligible study was evaluated by Jadad checklist.

RESULTS

Twelve studies met the inclusion criteria for the systematic review and were included in meta-analysis. There was a significant decrease in pain based on visual analogue scale (VAS) (mean difference [MD] 16.07, 95% confidence interval [CI] [9.57, 22.57], P < .00001, I = 88%, n = 966), and lumbar spine function in Oswestry disability index (ODI) (MD 7.12, 95% CI [3.77, 10.47], P < .00001, I = 87%, n = 468) comparing spa therapy group to control group. Methodological assessment for included studies showed that the study's quality is associated with lacking blinding.

CONCLUSION

This updated meta-analysis confirmed that spa therapy can benefit pain reliving and improve lumbar spine function among patients with CLBP. Physiotherapy of subgroup analysis indicated that it can improve lumbar spine function. However, these conclusions should be treated with caution due to limited studies. More high-quality RCTs with double-blind design, larger sample size, and longer follow-up should be employed to improve the validity of study results.

Pain quality descriptors in community-dwelling older adults with nonmalignant pain

This study aimed to characterize the prevalence of various pain qualities in older adults with chronic nonmalignant pain and determine the association of pain quality to other pain characteristics namely: severity, interference, distribution, and pain-associated conditions. In the population-based MOBILIZE Boston Study, 560 participants aged ≥70 years reported chronic pain in the baseline assessment, which included a home interview and clinic exam. Pain quality was assessed using a modified version of the McGill Pain Questionnaire (MPQ) consisting of 20 descriptors from which 3 categories were derived: cognitive/affective, sensory, and neuropathic. Presence of ≥2 pain-associated conditions was significantly associated with 18 of the 20 pain quality descriptors. Sensory descriptors were endorsed by nearly all older adults with chronic pain (93%), followed by cognitive/affective (83.4%) and neuropathic descriptors (68.6%). Neuropathic descriptors were associated with the greatest number of pain-associated conditions including osteoarthritis of the hand and knee. More than half of participants (59%) endorsed descriptors in all 3 categories and had more severe pain and interference, and multisite or widespread pain than those endorsing 1 or 2 categories. Strong associations were observed between pain quality and measures of pain severity, interference, and distribution (P < 0.0001). Findings from this study indicate that older adults have multiple pain-associated conditions that likely reflect multiple physiological mechanisms for pain. Linking pain qualities with other associated pain characteristics serve to develop a multidimensional approach to geriatric pain assessment. Future research is needed to investigate the physiological mechanisms responsible for the variability in pain qualities endorsed by older adults.

Effects of Myofascial Release in Nonspecific Chronic Low Back Pain: A Randomized Clinical Trial

STUDY DESIGN

Double-blind, randomized parallel sham-controlled trial with concealed allocation and intention-to treat analysis.

OBJECTIVE

To investigate the effects of an isolate myofascial release (MFR) protocol on pain, disability, and fear-avoidance beliefs in patients with chronic low back pain (CLBP).

SUMMARY OF BACKGROUND DATA

MFR is a form of manual medicine widely used by physiotherapists in the management of different musculoskeletal pathologies. Up to this moment, no previous studies have reported the effects of an isolated MFR treatment in patients with CLBP.

METHODS

Fifty-four participants, with nonspecific CLBP, were randomized to MFR group (n = 27) receiving four sessions of myofascial treatment, each lasting 40 minutes, and to control group (n = 27) receiving a sham MFR. Variables studied were pain measured by means Short Form McGill Pain Questionnaire (SF-MPQ) and visual analog scale (VAS), disability measured with Roland Morris Questionnaire, and fear-avoidance beliefs measured with Fear-Avoidance Beliefs Questionnaire.

RESULTS

Subjects receiving MFR displayed significant improvements in pain (SF-MPQ) (mean difference -7.8; 95% confidence interval [CI]: -14.5 to -1.1, P = 0.023) and sensory SF-MPQ subscale (mean difference -6.1; 95% CI: -10.8 to -1.5, P = 0.011) compared to the sham group, but no differences were found in VAS between groups. Disability and the Fear-Avoidance Beliefs Questionnaire score also displayed a significant decrease in the MFR group (P < 0.05) as compared to sham MFR.

CONCLUSION

MFR therapy produced a significant improvement in both pain and disability. Because the minimal clinically important differences in pain and disability are, however, included in the 95% CI, we cannot know whether this improvement is clinically relevant.

LEVEL OF EVIDENCE

2.

Neonatal pain: What's age got to do with it?

Background:

The neurobiology of neonatal pain processing, especially in preterm infants, differs significantly from older infants, children, adolescence, and adults. Research suggests that strong painful procedures or repeated mild procedures may permanently modify individual pain processing. Acute injuries at critical developmental periods are risk factors for persistent altered neurodevelopment. The purpose of this narrative review is to present the seminal and current literature describing the unique physiological aspects of neonatal pain processing.

Methods:

Articles describing the structures and physiological processes that influence neonatal pain were identified from electronic databases Medline, PubMed, and CINAHL.

Results:

The representation of neonatal pain physiology is described in three processes: Local peripheral nervous system processes, referred to as transduction; spinal cord processing, referred to as transmission and modulation; and supraspinal processing and integration or perception of pain. The consequences of undermanaged pain in preterm infants and neonates are discussed.

Conclusion:

Although the process and pain responses in neonates bear some similarity to processes and pain responses in older infants, children, adolescence, and adults; there are some pain processes and responses that are unique to neonates rendering them at risk for inadequate pain treatment. Moreover, exposure to repeated painful stimuli contributes to adverse long-term physiologic and behavioral sequelae. With the emergence of studies showing that painful experiences are capable of rewiring the adult brain, it is imperative that we treat neonatal pain effectively.

Vibration and rotation during biaxial pressure algometry is related with decreased and increased pain sensations

OBJECTIVE

During palpation, the pressure intensity and direction include minor deviations suggesting that standardized variations of the pressure intensity during pressure algometry may optimize the stimulus efficacy. This study examined the perceived pain outcome and reliability of a biaxial (bidirectional) algometer exerting rotational and vibratory stimulation on top of the basic pressure.

METHODS

In 24 healthy subjects, pressure pain thresholds (PPTs) were recorded with a linear pressure gradient (30 kPa/s) applied by a 1-cm(2) probe bilaterally on the tibialis anterior muscle via biaxial and handheld algometers. During constant pressure stimulation (5 seconds, 75%, 100%, 125% PPT), rotational (45°, 90°, and 180°), linear vibrational (15, 25, and 50 Hz), and radial vibrational stimulations (5, 15, and 25 Hz) were applied randomly via regular and fanning rounded probes (1 cm(2)). Subjects rated perceived pain on a 10-cm visual analogue scale on two occasions separated by 1 week period.

RESULTS

Repeated measures analysis of variance revealed enhanced effect of rotation angle (P < 0.001), probe (P < 0.001), and radial vibration frequency (P < 0.02), and suppressing effect of axial vibration frequency (P < 0.03) on pain perception, relative to basic pressure alone. PPT reliability of biaxial and handheld algometers showed averaged intraclass correlation coefficient of 0.94 and 0.945, and coefficient of variations of 15.4 and 13.5%, respectively.

CONCLUSIONS

PPT assessment and multidirectional stimulations can be exerted reliably via biaxial algometer. Linear vibrational stimulation effect on pressure pain perception verified the inhibitory interaction between simultaneous pressure stimulation of low-threshold mechanoreceptors and nociceptors, while radial vibration and rotational stimulation showed facilitatory effects.

Mechanisms and therapeutic implications of the placebo effect in neurological and psychiatric conditions

The power of a placebo to effect clinically meaningful neurobiological change comparable to pharmacological therapies has been demonstrated, although the mechanisms are not fully understood. Predicting placebo responsiveness has only recently received more attention, but psychological disposition, contextual and biological factors are now known to dramatically affect a person's susceptibility to the placebo effect. The placebo effect depends upon expectancies that can be modified in a number of ways, including conditioning through explicit or implicit learned associations. Based on the dopaminergic response to anticipation of benefit in Parkinson's disease, it was suggested that the placebo effect can be seen as analogous to the expectation of reward. Dopaminergic pathways have since been implicated in the placebo response in pain and depression. Additionally, endogenous opioid release is known to mediate many forms of placebo analgesia. We provide an overview of the mechanisms and the therapeutic implications of the placebo effect in neurological and psychiatric conditions. We include evidence for detrimental effects arising from seemingly inert interventions, termed the 'nocebo effect.' Neuroimaging has critically advanced the study of the placebo effect and provides some of the strongest evidence for the mechanisms of this phenomenon prevalent across an array of human health-related circumstances. This review specifically focuses on mechanisms of the placebo effect in the three conditions that have most significantly demonstrated this effect and for which a plausible physiological basis can be identified: pain, PD and depression. Other neurological and psychiatric diseases reviewed include multiple sclerosis, Huntington's disease, Alzheimer's disease, schizophrenia and epilepsy.

Massage therapy for cardiac surgery patients--a randomized trial

OBJECTIVES

To determine whether massage significantly reduces anxiety, pain, and muscular tension and enhances relaxation compared with an equivalent period of rest time after cardiac surgery. The feasibility of delivering the treatment, effects on heart rate, blood pressure, and respiratory rate, and patient satisfaction were also assessed.

METHODS

Elective cardiac surgery patients were randomized to receive massage or rest time at 2 points after surgery. Visual analog scales were used to measure pain, anxiety, relaxation, muscular tension, and satisfaction. Heart rate, respiratory rate, and blood pressure were measured before and after treatment. Focus groups and feedback were used to collect qualitative data about clinical significance and feasibility.

RESULTS

A total of 152 patients (99% response rate) participated. Massage therapy produced a significantly greater reduction in pain (P = .001), anxiety (P < .0001), and muscular tension (P = .002) and increases in relaxation (P < .0001) and satisfaction (P = .016) compared to the rest time. No significant differences were seen for heart rate, respiratory rate, and blood pressure. Pain was significantly reduced after massage on day 3 or 4 (P < .0001) and day 5 or 6 (P = .003). The control group experienced no significant change at either time. Anxiety (P < .0001) and muscular tension (P < .0001) were also significantly reduced in the massage group at both points. Relaxation was significantly improved on day 3 or 4 for both groups (massage, P < .0001; rest time, P = .006), but only massage was effective on day 5 or 6 (P < .0001). Nurses and physiotherapists observed patient improvements and helped facilitate delivery of the treatment by the massage therapists on the ward.

CONCLUSIONS

Massage therapy significantly reduced the pain, anxiety, and muscular tension and improves relaxation and satisfaction after cardiac surgery.

Acute postoperative pain at rest after hip and knee arthroplasty: severity, sensory qualities and impact on sleep

INTRODUCTION

The management of acute postoperative pain poses a significant challenge in surgical specialities. Despite the prevalence and impact of acute postoperative pain, there is a paucity of published data regarding its occurrence and sensory qualities after joint replacement.

HYPOTHESIS

That a proportion of patients would experience severe acute postoperative pain at rest after total hip replacement (THR) and total knee replacement (TKR).

MATERIALS AND METHODS

Pain was assessed preoperatively, and then five times daily for the first three postoperative days in 105 THR and TKR patients. Pain severity was assessed using a pain Visual Analogue Scale and the sensory qualities of pain were assessed using the pain descriptors from the Short-Form McGill Pain Questionnaire.

RESULTS

Median acute pain scores peaked on the first postoperative day, with 58% of TKR patients and 47% of THR patients reporting moderate-severe pain. Preoperative pain was most frequently described as aching, stabbing and sharp, whereas acute postoperative pain was described as aching, heavy and tender. Night pain disturbed between 44-57% of TKR patients and 21-52% of THR patients on postoperative nights 1-3.

DISCUSSION

These findings demonstrate that acute postoperative pain at rest after joint replacement, particularly TKR, is poorly managed, although it does not reach the severity of preoperative pain.

LEVEL OF EVIDENCE

Level IV (observational cohort study).

Music as nursing intervention for pain in five Asian countries*

BACKGROUND

The use of music as intervention for relieving pain has increased in recent years, prompting its growing use among the people of the western world. However, among Asians, music has long been used for this purpose and continues to be so today. Despite this common knowledge, Asians have not generally written about the therapeutic effects of music. Consequently, most of the published research studies supporting this claim were conducted in western settings using western music.

PURPOSE

To describe the use of music as intervention in painful conditions as experienced by people in five Asian countries: China, Thailand, Philippines, South Korea and Taiwan.

METHOD

Descriptive survey of studies using music as intervention for painful conditions conducted in selected five Asian countries.

FINDINGS

Twelve studies including theses and dissertations, published and unpublished, were found; however, only nine met the inclusion criteria. Data were categorized according to research design, sample size, gender, age, duration of music, frequency of music intervention, types of pain and instruments used to measure pain, conceptual or theoretical frameworks and statistical significance of the study. Five of the nine studies declared significant decrease in pain, while three reported mixed results. Fundamentally, the findings of the studies suggested that with music, relief of pain was possible.

IMPLICATIONS

The mixed results imply the need for further investigation of the effects of music in painful conditions. Thus, the authors suggest continuing studies on the effects of music as intervention in painful conditions, and encourage increasing global dissemination of these studies, particularly in international journals.

Prostatectomy patients' postoperative pain assessment in the recovery room

AIM

This paper reports a study to assess the usability and use of different pain assessment tools and to compare patients' and nurses' pain assessments in the recovery room after prostatectomy.

BACKGROUND

Pain assessment is the first step towards providing adequate pain relief but poses problems because of the subjective nature of the pain experience and the lack of quantifiable measurements. Pain tools have been tested in several clinical settings, but not in the recovery room.

METHODS

Data were collected in the recovery room from 45 consecutive patients who had undergone prostatectomy by asking them to evaluate their pain intensity using visual analogue scale, numeric rating scale and verbal expressions. One of two research nurses measured patients' pain at regular intervals and at the same time as the patients. Physiological parameters were also evaluated. Data were analysed as frequencies and percentages. Sum variables were formed and results were analysed using Spearman's rank correlation, Pearson's correlation and with multiple regression analysis.

RESULTS

Patients varied in their ability to assess the intensity of their pain using different tools, but assessments were correlated with each other and with nurses' estimations. Nurses and patients obtained similar assessments, but nurses both underestimated and overestimated patients' pain. Patients' verbal assessments varied widely. Patients' and nurses' pain assessments showed no association with patients' pulse or mean arterial blood pressure.

CONCLUSIONS

According to our results, it is not totally clear whether pain tools are usable in the recovery room. This issue calls for further research.

Music reduces sensation and distress of labor pain

Labor pain is often severe, and analgesic medication may not be indicated. In this randomized controlled trial we examined the effects of music on sensation and distress of pain in Thai primiparous women during the active phase of labor. The gate control theory of pain was the theoretical framework for this study. Randomization with a computerized minimization program was used to assign women to a music group (n = 55) or a control group (n = 55). Women in the intervention group listened to soft music without lyrics for 3 hours starting early in the active phase of labor. Dual visual analog scales were used to measure sensation and distress of pain before starting the study and at three hourly posttests. While controlling for pretest scores, one-way repeated measures analysis of covariance indicated that those in the music group had significantly less sensation and distress of pain than did the control group (F (1, 107) = 18.69, p <.001, effect size =.15, and F (1, 107) = 14.87, p <.001, effect size =.12), respectively. Sensation and distress significantly increased across the 3 hours in both groups (p <.001), except for distress in the music group during the first hour. Distress was significantly lower than sensation in both groups (p <.05). In this controlled study, music--a mild to moderate strength intervention--consistently provided significant relief of severe pain across 3 hours of labor and delayed the increase of affective pain for 1 hour. Nurses can provide soft music to laboring women for greater pain relief during the active phase when contractions are strong and women suffer.

Efficacy and safety of sucrose for procedural pain relief in preterm and term neonates

BACKGROUND

Preterm and acutely ill term neonates who are hospitalized in a neonatal intensive care unit are subjected to multiple frequent invasive and painful procedures aimed at improving their outcome. Although several trials to determine the efficacy of sucrose for managing procedural pain in preterm and acutely ill term neonates have been developed, these have generally lacked methodological rigor and have not provided clinicians with clear practice guidelines.

OBJECTIVES

To compare the efficacy and safety of three interventions for relieving procedural pain associated with heel lances in preterm and term neonates, and to explore the influence of contextual factors including sex, severity of illness, and prior painful procedures on pain responses.

METHODS

In a randomized controlled trial, 190 neonates were stratified by gestational age and then randomized to receive (a) sucrose and nonnutritive sucking (n = 64), (b) sucrose alone (n = 62), or (c) sterile water and nonnutritive sucking (control) (n = 64) to evaluate the efficacy (pain response as measured using the Premature Infant Pain Profile) (Stevens, Johnson, Petryshen, & Taddio, 1996) and safety (adverse events) following a scheduled heel lance during the first week of life. Stratification was used to control for the effects of age on pain response.

RESULTS

Significant differences in pain response existed among treatment groups (F = 22.49, p <.001), with the lowest mean Premature Infant Pain Profile scores in the sucrose and nonnutritive sucking group. Efficacy of sucrose following a heel lance was not affected by severity of illness, postnatal age, or number of painful procedures. Intervention group and sex explained 12% of the variance in Premature Infant Pain Profile scores. Few adverse events occurred (n = 6), and none of them required medical or nursing interventions.

CONCLUSIONS

The combination of sucrose and nonnutritive sucking is the most efficacious intervention for single heel lances. Research on the effects of gestational age on the efficacy and safety of repeated doses of sucrose is required.

Pain management programs in hand therapy: a literature review and appraisal

This article analyzes literature on pain management programs in hand therapy. Philosophical and practical issues that may influence the approach to pain are reviewed. Possible explanations for the relative lack of interdisciplinary/comprehensive approaches to pain are put forth. Conditions under which more comprehensive treatment should be considered are discussed.