Myofascial pain - A major player in musculoskeletal pain.

Myofascial pain is a soft tissue pain syndrome with local and referred musculoskeletal pain arising from trigger points. Myofascial pain and myofascial pain syndromes are among some of the most common acute and chronic pain conditions. Myofascial pain can exist independently of other pain generators or can coexist with or is secondary to other acute and chronic painful musculoskeletal conditions. Myofascial pain is most effectively treated with a multimodal treatment plan including injection therapy (known as trigger point injections, physical therapy, postural or ergonomic correction, and treatment of underlying musculoskeletal pain generators. The objectives of this review are to outline the prevalence of myofascial pain, describe the known pathophysiology of myofascial pain and trigger points, discuss the clinical presentation of myofascial pain, and present evidence-based best practices for pharmacologic, non-pharmacologic, and interventional treatments for myofascial pain.

Musculoskeletal and Neuropathic Pain in COVID-19.

Chronic pain constitutes a significant disease burden globally and accounts for a substantial portion of healthcare spending. The COVID-19 pandemic contributed to an increase in this burden as patients presented with musculoskeletal or neuropathic pain after contracting COVID-19 or had their chronic pain symptoms exacerbated by the virus. This extensive literature review analyzes the epidemiology of pain pre-pandemic, the costs associated with the COVID-19 pandemic, the impact of the virus on the body, mechanisms of pain, management of chronic pain post-pandemic, and potential treatment options available for people living with chronic pain who have had or are currently infected with COVID-19.

Investigation of patients' understanding of fibromyalgia: Results from an online qualitative survey.

OBJECTIVE: An important component to effective fibromyalgia treatment is patient education about the condition. While previous educational interventions have been developed, these have not incorporated the lived experiences of patients and may not address common misunderstandings among those who may benefit from these interventions. This study aimed to explore understanding, confusion, and gaps in knowledge about fibromyalgia among those who report a fibromyalgia diagnosis. METHODS: Participants were recruited via clinic flyers and the social media page of a chronic pain research laboratory. Participants completed an online survey that assessed their knowledge of fibromyalgia via open-ended questions. Responses were analyzed via thematic analysis to identify, analyze, and report themes. RESULTS: Thirty-eight participants completed the survey (63% female, ages 18-68). Common themes that arose from patients included being unsure of the cause of their fibromyalgia, frustration and confusion about the random/variable nature of symptoms and flares, feeling that their condition was invisible, and desiring more information on available treatments. CONCLUSION: Participants in this study expressed confusion about many aspects of fibromyalgia and a desire for more understanding from others in their life about this condition. PRACTICE IMPLICATIONS: Future interventions would benefit from tailoring fibromyalgia education to the specific knowledge and lived experiences of patients.

Localized and Widespread Chronic Pain in Sexual and Gender Minority People - An Analysis of The PRIDE Study.

Sex related differences, without taking gender into account, in chronic pain have been widely researched over the past few decades in predominantly cisgender and heterosexual populations. Historically, chronic pain conditions have a higher incidence and prevalence in cisgender women, including but not limited to fibromyalgia, irritable bowel syndrome, and migraine. The goal of the present study was to identify and characterize the presence and characteristics of chronic pain in SM and GM persons using data from The PRIDE Study, which is the first large-scale, long-term national cohort health study of people who identify as lesbian, gay, bisexual, transgender, queer, or as another sexual or gender minority person. A total of 6189 adult participants completed The PRIDE Study 2022 Annual Questionnaire at the time of data analysis. A total of 2462 participants reported no chronic pain, leaving 2935 participants who reported experiencing chronic pain. The findings from this study highlight that chronic pain is present to a significant degree in sexual and gender minority adults who participated in The PRIDE Study with chronic spine pain being the most common location/region of pain. Notably, more than one-third of non-binary persons, transgender men, and people who selected another gender experienced chronic widespread pain, defined by having 3 or more total regions of chronic pain. The lowest prevalence of chronic widespread pain was among transgender women and cisgender men. When considering sexual orientation, the highest prevalence of widespread pain was in participants who selected another sexual orientation, followed by queer and asexual, demisexual, gray ace, with the lowest prevalence of chronic widespread pain being in those who identify as straight or heterosexual, bisexual, pansexual, gay, and lesbian. Future studies are planned to elucidate how a variety of biopsychosocial mechanisms may influence chronic pain in sexual and gender minority persons.

The Prevalence and Nature of Eating and Swallowing Problems in Adults with Fibromyalgia: A Systematic Review.

Fibromyalgia is a complex chronic pain condition characterized by widespread pain, fatigue, cognitive dysfunction, and sleep disturbances. People with fibromyalgia can experience both autonomic and somatic disturbances, cognitive and mental health symptoms, and hypersensitivity to external stimuli. Fibromyalgia often co-occurs with a range of well-researched comorbidities (e.g., temporomandibular disorders, migraine, and irritable bowel syndrome). However, emerging research suggests that individuals with fibromyalgia also often experience eating, drinking, and swallowing problems (e.g., odynophagia, glossodynia, etc.). However, there is very little known about these issues, their psychosocial impact, or the best means of managing them clinically. As such, the aim of this research was to examine the epidemiology, prevalence and nature of eating and swallowing problems in adults with fibromyalgia as reported within previous research. A systematic search of electronic databases, selected conference proceedings, and reference lists was completed in March 2021, with no date or language restrictions. Studies reporting the presence and nature of eating and drinking problems in this cohort were included. Eligibility was assessed by two independent reviewers who also critically appraised the included studies using the Joanna Briggs Tool. This literature search yielded a total of 38 potentially eligible studies, with 6 studies included in analysis. Studies were highly heterogeneous in methodology and design, with meta-analysis showing that dysphagia and GERD are prevalent in fibromyalgia patients (51.9% and 25.9%, respectively), among other issues. From review of existing literature, eating and swallowing problems appear to be common among adults with fibromyalgia, with potential additional repercussions for activity, participation, and quality of life. Further research is required to prospectively investigate these issues, with patient and public involvement necessary to guide impactful research planning.

Low-dose naltrexone's utility for non-cancer centralized pain conditions: a scoping review.

BACKGROUND: At low doses, naltrexone (LDN) has been shown to modulate inflammation through the interruption of microglial cell activation within the central nervous system. One of the most likely contributors to centralized pain is changes in microglial cell processing. Therefore, it has been postulated that LDN can be used to manage patients with pain resulting from central sensitization due to this relationship. This scoping review aims to synthesize the relevant study data for LDN as a novel treatment strategy for various centralized pain conditions. METHODS: A comprehensive literature search was conducted in PubMed, Embase, and Google Scholar, guided by the Scale for Assessment of Narrative Review Articles (SANRA) criteria. RESULTS: Forty-seven studies related to centralized pain conditions were identified. Many of the studies were case reports/series and narrative reviews, but a few randomized control trials have been conducted. Overall, the body of evidence revealed improvement in patient-reported pain severity and in outcomes related to hyperalgesia, physical function, quality of life, and sleep. Variability in dosing paradigms and the time to patient response was present in the reviewed studies. CONCLUSIONS: Evidence synthesized for this scoping review supports the ongoing use of LDN for the treatment of refractory pain in various centralized chronic pain conditions. Upon review of the currently available published studies, it is apparent that further high-quality, well-powered randomized control trials need to be conducted to establish efficacy, standardization for dosing, and response times. In summary, LDN continues to offer promising results in the management of pain and other distressing symptoms in patients with chronic centralized pain conditions.

Abnormal intraepidermal nerve fiber density in disease: A scoping review.

Background: Intraepidermal nerve fiber density (IENFD) has become an important biomarker for neuropathy diagnosis and research. The consequences of reduced IENFD can include sensory dysfunction, pain, and a significant decrease in quality of life. We examined the extent to which IENFD is being used as a tool in human and mouse models and compared the degree of fiber loss between diseases to gain a broader understanding of the existing data collected using this common technique. Methods: We conducted a scoping review of publications that used IENFD as a biomarker in human and non-human research. PubMed was used to identify 1,004 initial articles that were then screened to select articles that met the criteria for inclusion. Criteria were chosen to standardize publications so they could be compared rigorously and included having a control group, measuring IENFD in a distal limb, and using protein gene product 9.5 (PGP9.5). Results: We analyzed 397 articles and collected information related to publication year, the condition studied, and the percent IENFD loss. The analysis revealed that the use of IENFD as a tool has been increasing in both human and non-human research. We found that IENFD loss is prevalent in many diseases, and metabolic or diabetes-related diseases were the most studied conditions in humans and rodents. Our analysis identified 73 human diseases in which IENFD was affected, with 71 reporting IENFD loss and an overall average IENFD change of -47%. We identified 28 mouse and 21 rat conditions, with average IENFD changes of -31.6% and -34.7%, respectively. Additionally, we present data describing sub-analyses of IENFD loss according to disease characteristics in diabetes and chemotherapy treatments in humans and rodents. Interpretation: Reduced IENFD occurs in a surprising number of human disease conditions. Abnormal IENFD contributes to important complications, including poor cutaneous vascularization, sensory dysfunction, and pain. Our analysis informs future rodent studies so they may better mirror human diseases impacted by reduced IENFD, highlights the breadth of diseases impacted by IENFD loss, and urges exploration of common mechanisms that lead to substantial IENFD loss as a complication in disease.

Autonomic nervous system markers of music-elicited analgesia in people with fibromyalgia: A double-blind randomized pilot study.

Purpose: To investigate the feasibility of using music listening by adults with fibromyalgia (FM) as a potential tool for reducing pain sensitivity. Patients and methods: We report results from a double-blind two-arm parallel randomized pilot study (NCT04059042) in nine participants with FM. Pain tolerance and threshold were measured objectively using quantitative sensory tests; autonomic nervous system (ANS) reactivity was measured with an electrocardiogram. Participants were randomized to listen to instrumental Western Classical music or a nature sound control to test whether music listening elicits greater analgesic effects over simple auditory distraction. Participants also completed separate control testing with no sound that was counterbalanced between participants. Results: Participants were randomized 1:1 to music or nature sounds (four Music and five Nature). Although the groups were not different on FM scores, the Music group had marginally worse temporal pain summation (p = 0.06), and the Nature group had higher anxiety scores (p < 0.05). Outcome measures showed a significant difference between groups in the magnitude of change in temporal summation between sessions (p < 0.05), revealing that the Nature group had greater pain reduction during audio compared to silence mode, while the Music group had no difference between the sessions. No significant effects were observed for either mechanical pain tolerance or ANS testing. Within the Music group, there was a trend of vagal response increase from baseline to music listening, but it did not reach statistical significance; this pattern was not observed in the Nature group. Conclusion: Auditory listening significantly altered pain responses. There may be a greater vagal response to music vs. nature sounds; however, results could be due to group differences in pain and anxiety. This line of study will help in determining whether music could be prophylactic for people with FM when acute pain is expected.

Management of Postoperative Pain in Patients Following Spine Surgery: A Narrative Review.

Perioperative pain management is a unique challenge in patients undergoing spine surgery due to the increased incidence of both pre-existing chronic pain conditions and chronic postsurgical pain. Peri-operative planning and counseling in spine surgery should involve an interdisciplinary approach that includes consideration of patient-level risk factors, as well as pharmacologic and non-pharmacologic pain management techniques. Consideration of psychological factors and patient focused education as an adjunct to these measures is paramount in developing a personalized perioperative pain management plan. Understanding the currently available body of knowledge surrounding perioperative opioid management, management of opioid use disorder, regional/neuraxial anesthetic techniques, ketamine/lidocaine infusions, non-opioid oral analgesics, and behavioral interventions can be useful in developing a comprehensive, multi-modal treatment plan among patients undergoing spine surgery. Although many of these techniques have proved efficacious in the immediate postoperative period, long-term follow-up is needed to define the impact of such approaches on persistent pain and opioid use. Future techniques involving the use of precision medicine may help identify phenotypic and physiologic characteristics that can identify patients that are most at risk of developing persistent postoperative pain after spine surgery.

Trigger Point Injections.

Myofascial pain and myofascial pain syndromes are among some of the most common acute and chronic pain conditions. Many interventional procedures can be performed in both an acute and chronic pain setting to address myofascial pain syndromes. Trigger point injections can be performed with or without imaging guidance such as fluoroscopy and ultrasound; however, the use of imaging in years past has been recommended to improve patient outcome and safety. Injections can be performed using no injectate (dry needling), or can involve the administration of local anesthetics, botulinum toxin, or corticosteroids.

Consensus practice guidelines on interventions for cervical spine (facet) joint pain from a multispecialty international working group.

BACKGROUND: The past two decades have witnessed a surge in the use of cervical spine joint procedures including joint injections, nerve blocks and radiofrequency ablation to treat chronic neck pain, yet many aspects of the procedures remain controversial. METHODS: In August 2020, the American Society of Regional Anesthesia and Pain Medicine and the American Academy of Pain Medicine approved and charged the Cervical Joint Working Group to develop neck pain guidelines. Eighteen stakeholder societies were identified, and formal request-for-participation and member nomination letters were sent to those organizations. Participating entities selected panel members and an ad hoc steering committee selected preliminary questions, which were then revised by the full committee. Each question was assigned to a module composed of 4-5 members, who worked with the Subcommittee Lead and the Committee Chairs on preliminary versions, which were sent to the full committee after revisions. We used a modified Delphi method whereby the questions were sent to the committee en bloc and comments were returned in a non-blinded fashion to the Chairs, who incorporated the comments and sent out revised versions until consensus was reached. Before commencing, it was agreed that a recommendation would be noted with >50% agreement among committee members, but a consensus recommendation would require ≥75% agreement. RESULTS: Twenty questions were selected, with 100% consensus achieved in committee on 17 topics. Among participating organizations, 14 of 15 that voted approved or supported the guidelines en bloc, with 14 questions being approved with no dissensions or abstentions. Specific questions addressed included the value of clinical presentation and imaging in selecting patients for procedures, whether conservative treatment should be used before injections, whether imaging is necessary for blocks, diagnostic and prognostic value of medial branch blocks and intra-articular joint injections, the effects of sedation and injectate volume on validity, whether facet blocks have therapeutic value, what the ideal cut-off value is for designating a block as positive, how many blocks should be performed before radiofrequency ablation, the orientation of electrodes, whether larger lesions translate into higher success rates, whether stimulation should be used before radiofrequency ablation, how best to mitigate complication risks, if different standards should be applied to clinical practice and trials, and the indications for repeating radiofrequency ablation. CONCLUSIONS: Cervical medial branch radiofrequency ablation may provide benefit to well-selected individuals, with medial branch blocks being more predictive than intra-articular injections. More stringent selection criteria are likely to improve denervation outcomes, but at the expense of false-negatives (ie, lower overall success rate). Clinical trials should be tailored based on objectives, and selection criteria for some may be more stringent than what is ideal in clinical practice.

Consensus practice guidelines on interventions for cervical spine (facet) joint pain from a multispecialty international working group.

BACKGROUND: The past two decades have witnessed a surge in the use of cervical spine joint procedures including joint injections, nerve blocks and radiofrequency ablation to treat chronic neck pain, yet many aspects of the procedures remain controversial. METHODS: In August 2020, the American Society of Regional Anesthesia and Pain Medicine and the American Academy of Pain Medicine approved and charged the Cervical Joint Working Group to develop neck pain guidelines. Eighteen stakeholder societies were identified, and formal request-for-participation and member nomination letters were sent to those organizations. Participating entities selected panel members and an ad hoc steering committee selected preliminary questions, which were then revised by the full committee. Each question was assigned to a module composed of 4-5 members, who worked with the Subcommittee Lead and the Committee Chairs on preliminary versions, which were sent to the full committee after revisions. We used a modified Delphi method whereby the questions were sent to the committee en bloc and comments were returned in a non-blinded fashion to the Chairs, who incorporated the comments and sent out revised versions until consensus was reached. Before commencing, it was agreed that a recommendation would be noted with >50% agreement among committee members, but a consensus recommendation would require ≥75% agreement. RESULTS: Twenty questions were selected, with 100% consensus achieved in committee on 17 topics. Among participating organizations, 14 of 15 that voted approved or supported the guidelines en bloc, with 14 questions being approved with no dissensions or abstentions. Specific questions addressed included the value of clinical presentation and imaging in selecting patients for procedures, whether conservative treatment should be used before injections, whether imaging is necessary for blocks, diagnostic and prognostic value of medial branch blocks and intra-articular joint injections, the effects of sedation and injectate volume on validity, whether facet blocks have therapeutic value, what the ideal cut-off value is for designating a block as positive, how many blocks should be performed before radiofrequency ablation, the orientation of electrodes, whether larger lesions translate into higher success rates, whether stimulation should be used before radiofrequency ablation, how best to mitigate complication risks, if different standards should be applied to clinical practice and trials, and the indications for repeating radiofrequency ablation. CONCLUSIONS: Cervical medial branch radiofrequency ablation may provide benefit to well-selected individuals, with medial branch blocks being more predictive than intra-articular injections. More stringent selection criteria are likely to improve denervation outcomes, but at the expense of false-negatives (ie, lower overall success rate). Clinical trials should be tailored based on objectives, and selection criteria for some may be more stringent than what is ideal in clinical practice.

Understanding the Psychological, Physiological, and Genetic Factors Affecting Precision Pain Medicine: A Narrative Review.

PURPOSE: Precision pain medicine focuses on employing methods to assess each patient individually, identify their risk profile for disproportionate pain and/or the development of chronic pain, and optimize therapeutic strategies to target specific pathological processes underlying chronic pain. This review aims to provide a concise summary of the current body of knowledge regarding psychological, physiological, and genetic determinants of chronic pain related to precision pain medicine. METHODS: Following the Scale for the Assessment of Narrative Review Articles (SANRA) criteria, we employed PubMed/Medline to identify relevant articles using primary database search terms to query articles such as: precision medicine, non-modifiable factors, pain, anesthesiology, quantitative sensory testing, genetics, pain medicine, and psychological. RESULTS: Precision pain medicine provides an opportunity to identify populations at risk, develop personalized treatment strategies, and reduce side effects and cost through elimination of ineffective treatment strategies. As in other complex chronic health conditions, there are two broad categories that contribute to chronic pain risk: modifiable and non-modifiable patient factors. This review focuses on three primary determinants of health, representing both modifiable and non-modifiable factors, that may contribute to a patient's profile for risk of developing pain and most effective management strategies: psychological, physiological, and genetic factors. CONCLUSION: Consideration of these three domains is already being integrated into patient care in other specialties, but by understanding the role they play in development and maintenance of chronic pain, we can begin to implement both precision and personalized treatment regimens.

The impact of foot shock-induced stress on pain-related behavior associated with burn injury.

Acute pain is prevalent following burn injury and can often transition to chronic pain. Prolonged acute pain is an important risk factor for chronic pain and there is little preclinical research to address this problem. Using a mouse model of second-degree burn, we investigated whether pre-existing stress influences pain(sensitivity) after a burn injury. We introduced a contribution of stress in two different ways: (1) the use of foot-shock as a pre-injury stressor or (2) the use of A/J mice to represent higher pre-existing stress compared to C57Bl/6 mice. C57Bl/6 and A/J mice were exposed to repeated mild foot shock to induce stress for 10 continuous days and mice underwent either burn injury or sham burn injury of the plantar surface of the right hind paw. Assessments of mechanical and thermal sensitivities of the injured and uninjured paw were conducted during the shock protocol and at intervals up to 82-day post-burn injury. In both strains of mice that underwent burn injury, thermal hypersensitivity and mechanical allodynia appeared rapidly in the ipsilateral paw. Mice that were stressed took much longer to recover their hind paw mechanical thresholds to baseline compared to non-stressed mice in both burn and non-burn groups. Analysis of the two mouse strains revealed that the recovery of mechanical thresholds in A/J mice which display higher levels of baseline anxiety was shorter than C57Bl/6 mice. No differences were observed regarding thermal sensitivities between strains. Our results support the view that stress exposure prior to burn injury affects mechanical and thermal thresholds and may be relevant to as a risk factor for the transition from acute to chronic pain. Finally, genetic differences may play a key role in modality-specific recovery following burn injury.

Utilization of Low-Dose Naltrexone for Burning Mouth Syndrome: A Case Report.

Burning mouth syndrome is a chronic pain condition characterized by a burning sensation of the oropharynx. The pathophysiology of burning mouth syndrome includes peripheral and central sensitization. Treatment is generally aimed at symptom reduction. We describe a woman in her seventh decade with burning mouth syndrome that had been refractory to treatment for nearly a decade. Low-dose naltrexone has been reported to provide analgesia in central sensitization states and was successful in reducing pain severity in our patient. We conclude that low-dose naltrexone may be a therapeutic option for patients with burning mouth syndrome who are refractory to conventional therapies.

Infants' Use of Force to Defend Toys: The Origins of Instrumental Aggression.

The two aims of the study were (a) to determine when infants begin to use force intentionally to defend objects to which they might have a claim and (b) to examine the relationship between toddlers' instrumental use of force and their tendencies to make possession claims. Infants' and toddlers' reactions to peers' attempts to take their toys were assessed in three independent data sets in which the same observational coding system had been used (N = 200). To ensure that infants' use of force was goal-directed and not a simple physical reaction, we recorded infants' reactions when peers picked up toys that the focal infants had just put down, or were nearby or in the focal infants' mothers' laps. The use of force in response to peers' taking over toys was evident before the first birthday, but more common thereafter, although only a minority of children in each sample used force. Analysis of a combined data set revealed that force was deployed more often by 2-year-olds than younger infants, and was significantly associated with verbal references to people's possession of objects. These observations show that toddlers do deploy force intentionally to defend their possessions.

Peer relations in childhood.

We present a developmental model that describes normal peer relations and highlights processes that underlie the emergence of problems with peers in childhood. We propose that children's relationships with peers begin in the first years of life, with stable individual differences and preferences for particular peers emerging by three years of age. Social skills that facilitate peer relationships consolidate in the preschool years, during which time peer groups become structured with respect to friendship groups, gender, and dominance relations; some children begin to be rejected by their peers. In later childhood some children develop entrenched problems with peer relationships, in terms of loneliness, bullying and victimisation. Underlying cognitive and emotional processes that facilitate successful peer relationships at all ages are identified, and the extent to which peer relations play a causal role in the genesis of disorder is evaluated. A review of the evidence suggests that, rather than a simple pathway from problematic peer relations to disorder, there is a reciprocal relationship between children's problems with peers and their psychological problems from infancy to adolescence.

Exploring a neural-network account of age-of-acquisition effects using repetition priming of faces.

The question of whether age-of-acquisition (AoA), frequency, and repetition priming effects occur at a common stage or at different stages of processing is addressed. Two single-stage accounts (i.e., cumulative frequency and a neural-network simulation) are considered in regard to their predictions concerning the interactions between AoA and frequency with aging and priming effects. A repetition-priming face-classification task was conducted on both older and younger participants to test these predictions. Consistent with the predictions of the neural-network simulation, AoA had an effect on reaction times that could not be explained by cumulative frequency alone. Also, as predicted by the simulation, the size of the priming effect was determined by the cumulative frequency of the item. It is discussed how this evidence is supportive of the notion that AoA , frequency, and priming all have effects at a common and single stage during face processing.