Regional Pain Disorder Research Articles

Prevalence of Spinal Segmental Sensitization Syndrome in Outpatients Attending Physical Medicine and Rehabilitation Centers for Chronic Musculoskeletal Pain: A Multicenter Study

ObjectiveTo determine the prevalence of spinal segmental sensitization (SSS) syndrome, a regional pain disorder, among patients visiting physical medicine and rehabilitation centers (PM&RCs) for chronic musculoskeletal pain (CMSP). DesignAn observational, descriptive, cross-sectional study conducted from March to July 2023. SettingSeven PM&RCs from 5 cities, representing 3 care systems: Social Security (SS), Ministry of Health (MH), and private practice (PP). ParticipantsAll patients, regardless of age, attending a physiatry consultation for CMSP for the first time and who provided informed consent to participate were included. Nonprobabilistic sampling was employed. InterventionsNot applicable. Main Outcome MeasureWe estimated the overall prevalence of SSS syndrome as a percentage among patients with CMSP, stratified by health care institution, sex, age, and occupation type. We also recorded the spinal segments involved and any concomitant painful disorders (CPDs). SSS syndrome was diagnosed using standardized criteria. ResultsOf the eligible participants, 319 with CMSP were enrolled; 73.4% were women, and the median age of participants was 56.9 (range, 13-89y) years. The overall prevalence of SSS syndrome was 53.3%. Of these, 69.1%, 42.2%, and 13.8% were in the SS, MH, and PP systems, respectively. The most affected were female participants (56.4%), those aged 50-64 years (60.4%), and those with active jobs (58.8%). Most commonly, the lumbosacral and lumbar segments were affected, followed by the lower and middle cervical levels. Spine pathologies were the most common CPDs. ConclusionThe prevalence of SSS syndrome was high among patients who visited PM&RCs for CMSP and varied according to the care system. Further research on SSS syndrome is warranted to relieve the burden it poses on patients with CMSP and ensure proper diagnosis in clinical practice.

Diagnosis of complex regional pain syndrome

Complex regional pain syndrome (CRPS) is a chronic regional pain disorder that most frequently affects the limbs. It is characterized by hyperalgesia, allodynia, edema, motor disturbance, and vasomotor instability, and typically occurs following surgery or trauma. In type-I CRPS there is no confirmed nerve injury, while peripheral nerve injury is present in type-II CRPS. The multifactorial pathophysiological etiology of CRPS includes inflammation, autoimmune responses, abnormal cytokine production, autonomic dysfunction, altered blood flow, psychological factors, and central cortical reorganization. There are no specific laboratory diagnostic tools for CRPS, and so it is diagnosed clinically. The Budapest criteria are currently the most-accepted diagnostic criteria.

Treatment and management of myofascial pain syndrome.

Myofascial Pain Syndrome (MPS) is a regional pain disorder that affects every age-group and is characterized by the presence of trigger points (TrPs) within muscles or fascia. MPS is typically diagnosed via physical exam, and the general agreement for diagnostic criteria includes the presence of TrPs, pain upon palpation, a referred pain pattern, and a local twitch response. The prevalence of MPS among patients presenting to medical clinics due to pain ranges anywhere from 30 to 93%. This may be due to the lack of clear criteria and guidelines in diagnosing MPS. Despite the prevalence of MPS, its pathophysiology remains incompletely understood. There are many different ways to manage and treat MPS. Some include exercise, TrP injections, medications, and other alternative therapies. More research is needed to form uniformly-accepted diagnostic criteria and treatments.

AAPT Diagnostic Criteria for Peripheral Neuropathic Pain: Focal and Segmental Disorders

Peripheral neuropathic pain is among the most prevalent types of neuropathic pain. No comprehensive peripheral neuropathic pain classification system that incorporates contemporary clinical, diagnostic, biological, and psychological information exists. To address this need, this article covers the taxonomy for 4 focal or segmental peripheral neuropathic pain disorders, as part of the Analgesic, Anesthetic, and Addiction Clinical Trial Translations, Innovations, Opportunities, and Networks (ACTTION) public-private partnership and the American Pain Society (APS) collaborative to develop a standardized, evidence-based taxonomy initiative: the ACTTION-APS Pain Taxonomy (AAPT). The disorders—postherpetic neuralgia, persistent posttraumatic neuropathic pain, complex regional pain disorder, and trigeminal neuralgia—were selected because of their clinical and clinical research relevance. The multidimensional features of the taxonomy are suitable for clinical trials and can also facilitate hypothesis-driven case-control and cohort epidemiologic studies. PerspectiveThe AAPT peripheral neuropathic pain taxonomy subdivides the peripheral neuropathic pain disorders into those that are generalized and symmetric and those that are focal or segmental and asymmetric. In this article, we cover the focal and segmental disorders: postherpetic neuralgia, persistent posttraumatic neuropathic pain, complex regional pain disorder, and trigeminal neuralgia. The taxonomy is evidence-based and multidimensional, with the following dimensions: 1) core diagnostic criteria; 2) common features; 3) common medical and psychiatric comorbidities; 4) neurobiological, psychosocial, and functional consequences; and 5) putative neurobiological and psychosocial mechanisms, risk factors, and protective factors.

2016 Revisions to the 2010/2011 fibromyalgia diagnostic criteria.

The provisional criteria of the American College of Rheumatology (ACR) 2010 and the 2011 self-report modification for survey and clinical research are widely used for fibromyalgia diagnosis. To determine the validity, usefulness, potential problems, and modifications required for the criteria, we assessed multiple research reports published in 2010-2016 in order to provide a 2016 update to the criteria. We reviewed 14 validation studies that compared 2010/2011 criteria with ACR 1990 classification and clinical criteria, as well as epidemiology, clinical, and databank studies that addressed important criteria-level variables. Based on definitional differences between 1990 and 2010/2011 criteria, we interpreted 85% sensitivity and 90% specificity as excellent agreement. Against 1990 and clinical criteria, the median sensitivity and specificity of the 2010/2011 criteria were 86% and 90%, respectively. The 2010/2011 criteria led to misclassification when applied to regional pain syndromes, but when a modified widespread pain criterion (the "generalized pain criterion") was added misclassification was eliminated. Based on the above data and clinic usage data, we developed a (2016) revision to the 2010/2011 fibromyalgia criteria. Fibromyalgia may now be diagnosed in adults when all of the following criteria are met: CONCLUSIONS: The fibromyalgia criteria have good sensitivity and specificity. This revision combines physician and questionnaire criteria, minimizes misclassification of regional pain disorders, and eliminates the previously confusing recommendation regarding diagnostic exclusions. The physician-based criteria are valid for individual patient diagnosis. The self-report version of the criteria is not valid for clinical diagnosis in individual patients but is valid for research studies. These changes allow the criteria to function as diagnostic criteria, while still being useful for classification.

Sympathomimetic amine therapy found effective for treatment of refractory chronic complex regional pain syndrome (reflex sympathetic dystrophy)

Purpose: To determine if treatment with sympathomimetic amines could improve the pain from complex regional pain disorder (CRPD) which was keeping a woman from trying to conceive her second child. Materials and Methods: Dextroamphetamine sulfate was prescribed. Results: Within a short length of time the woman’s wrist pain considerably improved to the point that she is ready to try in vitro fertilization once again to have a second baby. Conclusions: Though sympathomimetic amines are used by some reproductive endocrinologists for unexplained infertility and unexplained recurrent miscarriages, the most common use by the gynecologist is for pelvic pain. Despite the thought by some clinicians and researchers that the etiology for CRPD may be related to sympathetic nervous system hyperactivity (and thus sympathomimetic amines could theoretically exacerbate the symptoms), in fact, the treatment with dextroamphetamine sulfate may turn out to be a new and possibly the most effective, least risky, and least expensive treatment to date for CRPD.

G365 Medical management of neuropathic pain in complex regional pain syndromes

AimPatients with Complex Regional Pain syndromes require multidisciplinary care to be managed effectively. Relief from the symptoms of neuropathic pain often requires the use of centrally acting medications, as well...

New insights into visceral hypersensitivity—clinical implications in IBS

A subset of patients with IBS have visceral hypersensitivity and/or somatic hypersensitivity. Visceral hypersensitivity might have use as a clinical marker of IBS and could account for symptoms of urgency for bowel movements, bloating and abdominal pain. The mechanisms that lead to chronic visceral hypersensitivity in patients who have IBS are unclear. However, several working models may be considered, including: nociceptive input from the colon that leads to hypersensitivity; increased intestinal permeability that induces a visceral nociceptive drive; and alterations in the expression of microRNAs in gastrointestinal tissue that might be delivered via blood microvesicles to other target organs, such as the peripheral and/or central nervous system. As such, the chronic visceral hypersensitivity that is present in a subset of patients with IBS might be maintained by both peripheral and central phenomena. The theories underlying the development of chronic visceral hypersensitivity in patients with IBS are supported by findings from new animal models in which hypersensitivity follows transient inflammation of the colon. The presence of somatic hypersensitivity and an alteration in the neuroendocrine system in some patients who have IBS suggests that multisystemic factors are involved in the overall disorder. Thus, IBS is similar to other chronic pain disorders, such as fibromyalgia, chronic regional pain disorder and temporomandibular joint disorder, as chronic nociceptive mechanisms are activated in all of these disorders.

Effects of treatment of peripheral pain generators in fibromyalgia patients

Fibromyalgia syndrome (FS) frequently co-occurs with regional pain disorders. This study evaluated how these disorders contribute to FS, by assessing effects of local active vs placebo treatment of muscle/joint pain sources on FS symptoms. Female patients with (1) FS + myofascial pain syndromes from trigger points ( n = 68), or (2) FS + joint pain ( n = 56) underwent evaluation of myofascial/joint symptoms [number/intensity of pain episodes, pressure pain thresholds at trigger/joint site, paracetamol consumption] and FS symptoms [pain intensity, pressure pain thresholds at tender points, pressure and electrical pain thresholds in skin, subcutis and muscle in a non-painful site]. Patients of both protocols were randomly assigned to two groups [34 each for (1); 28 each for (2)] to receive active or placebo local TrP or joint treatment [injection/hydroelectrophoresis] on days 1 and 4. Evaluations were repeated on days 4 and 8. After therapy, in active – but not placebo-treated groups: number and intensity of myofascial/joint episodes and paracetamol consumption decreased and pressure thresholds at trigger/joint increased ( p < 0.001); FS pain intensity decreased and all thresholds increased progressively in tender points and the non-painful site ( p < 0.0001). At day 8, all placebo-treated patients requested active local therapy (days 8 and 11) vs only three patients under active treatment. At a 3-week follow-up, FS pain was still lower than basis in patients not undergoing further therapy and had decreased in those undergoing active therapy from day 8 ( p < 0.0001). Localized muscle/joint pains impact significantly on FS, probably through increased central sensitization by the peripheral input; their systematic identification and treatment are recommended in fibromyalgia.

Risk Factors Predicting the Development of Widespread Pain From Chronic Back or Neck Pain

Emerging evidence suggests that some individuals with regional pain disorders go on to develop chronic widespread pain (CWP). However, the mechanism behind this transition and the nature of risk factors that predispose a person to develop CWP remain to be elucidated. The purpose of this study was to describe the frequency with which participants with chronic back or neck pain develop CWP and to determine the risk factors associated with this development. In a sample of 512 individuals, we found that nearly a quarter (22.6%) of subjects who presented with regional back or neck pain in 2001/2002 had developed CWP by 2007. Logistic regression indicated that 7 factors were associated with the transition to CWP: moderate or severe pain intensity, female gender, history of abuse, family history of CWP, severe interference with general activity, having 1 or more central sensitivity syndromes, and using more pain management strategies. History of abuse was not significant in multivariate analysis. Notably, number of depressive symptoms endorsed, pain duration, age, body mass index, number of medication classes used, and receipt of disability benefits were not significantly associated with this transition. This study offers insight into risk factors associated with the development of CWP. This information not only offers clues as to the mechanism behind the expansion of pain sensitivity from a regional pain locus to a widespread pain disorder but also provides insight as to how clinicians might mitigate this transition.

Clinical assessment of the osteoarthritis patient.

It is becoming apparent that the disease process of osteoarthritis should be regarded separately from the clinical syndrome of joint pain, use-related stiffness and disability. The latter may best be approached as a chronic regional pain disorder that requires attention to physical, psychological and social factors as well as those related to the disease process. This chapter sets out to look at some of the practical implications of taking this view for the clinical assessment. Starting with the syndrome of hip, knee or hand pain in older adults in the community, we consider what leads people to consult, what the important features to assess might be, the role of imaging in the clinical assessment of osteoarthritis, and finally how a management plan could be formulated. The usefulness of assessing clinical osteoarthritis as a regional pain disorder is uncertain. Even if this were demonstrated, the concept of osteoarthritis as a structural disease should be retained as an integral part.

Frequency and impact of regional musculoskeletal disorders.

Regional musculoskeletal disorders are a major cause of morbidity both in the community and in the workplace. They comprise a heterogeneous group of conditions that are, for the most part, poorly characterized. Consequently, agreed diagnostic criteria have not existed for many of these disorders, and epidemiological investigations have used varied or ill-defined approaches to case definition. This chapter describes our current understanding of the epidemiology of regional pain disorders and details the strengths and weaknesses of the available data. Pain syndromes can be divided anatomically into those which cause generalized pain, such as fibromyalgia syndrome and myofascial pain syndromes, and those which are confined to one regional anatomical area. The latter group comprise those of the neck, shoulder, elbow, wrist/hand, hip, knee and ankle/foot. Current information is considered on the known risk factors for disorders at these sites, in addition to their impact upon both the individual and society.