Circadian pain patterns in human pain conditions - A systematic review.

BACKGROUND: Chronobiology is the science of how physiological processes in the body follow a pattern of time. Pain has been shown to follow a circadian rhythm, with different types of pain having variable expression along this rhythm. OBJECTIVE: This article reviews the nature of diurnal variations in pain along with a discussion of the mechanisms of circadian rhythm of pain. EVIDENCE REVIEW: We conducted a literature search on the PubMed and Google Scholar electronic databases, through April 2022. Publications were screened for English language, full-text availability, and human subjects. Randomized controlled trials and observational trials were included. Data were extracted from studies on patients with acute or chronic pain phenotypes, which provide pain severity data and corresponding diurnal time points. FINDINGS: The literature search led to the inclusion of 39 studies. A circadian pattern of pain was found to be present in nociceptive, neuropathic, central, and mixed pain states. Postoperative pain, fibromyalgia, trigeminal neuralgia, and migraines were associated with higher pain scores in the morning. Temporomandibular joint pain, neuropathic pain, labor pain, biliary colic, and cluster headaches increased throughout the day to reach a peak in the evening or night. Arthritis and cancer pain were not associated with any circadian rhythmicity. Furthermore, the circadian rhythm of pain was not found to be altered in patients on analgesics. CONCLUSION: The results of this review suggest that an understanding of diurnal variation may help improve therapeutic strategies in pain management, for instance through analgesic titration.

Low back pain.

Low back pain covers a spectrum of different types of pain (eg, nociceptive, neuropathic and nociplastic, or non-specific) that frequently overlap. The elements comprising the lumbar spine (eg, soft tissue, vertebrae, zygapophyseal and sacroiliac joints, intervertebral discs, and neurovascular structures) are prone to different stressors, and each of these, alone or in combination, can contribute to low back pain. Due to numerous factors related to low back pain, and the low specificity of imaging and diagnostic injections, diagnostic methods for this condition continue to be a subject of controversy. The biopsychosocial model posits low back pain to be a dynamic interaction between social, psychological, and biological factors that can both predispose to and result from injury, and should be considered when devising interdisciplinary treatment plans. Prevention of low back pain is recognised as a pivotal challenge in high-risk populations to help tackle high health-care costs related to therapy and rehabilitation. To a large extent, therapy depends on pain classification, and usually starts with self-care and pharmacotherapy in combination with non-pharmacological methods, such as physical therapies and psychological treatments in appropriate patients. For refractory low back pain, a wide range of non-surgical (eg, epidural steroid injections and spinal cord stimulation for neuropathic pain, and radiofrequency ablation and intra-articular steroid injections for mechanical pain) and surgical (eg, decompression for neuropathic pain, disc replacement, and fusion for mechanical causes) treatment options are available in carefully selected patients. Most treatment options address only single, solitary causes and given the complex nature of low back pain, a multimodal interdisciplinary approach is necessary. Although globally recognised as an important health and socioeconomic challenge with an expected increase in prevalence, low back pain continues to have tremendous potential for improvement in both diagnostic and therapeutic aspects. Future research on low back pain should focus on improving the accuracy and objectivity of diagnostic assessments, and devising treatment algorithms that consider unique biological, psychological, and social factors. High-quality comparative-effectiveness and randomised controlled trials with longer follow-up periods that aim to establish the efficacy and cost-effectiveness of low back pain management are warranted.

A Retrospective Analysis of Gabapentinoid and Opioids to Opioid Monotherapy for Pain Relief in Patients with Chronic Neck and Low Back Pain.

OBJECTIVE: We compared the reduction in pain and opioid consumption in patients with chronic spinal pain on concomitant gabapentinoids and opioids with patients using opioids only. DESIGN: This was a retrospective chart review of patients with chronic neck or low back pain who were on opioids with at least a 24-month follow-up. SETTING: Single-center pain clinic in an urban setting. SUBJECTS: 167 patients with chronic spinal pain lasting at least six months. METHODS: Patients on gabapentin or pregabalin were included in the gabapentinoid group, while the other patients were included in the non-gabapentinoid group. Primary outcome was assessment of pain scores measured via a numeric rating scale (NRS), and secondary outcomes were response to the treatment (>2 point reduction on NRS) and daily opioid use measured in morphine milliequivalents. RESULTS: Pain scores were reduced in the first six months and plateaued after that in both groups. At the end of 24 months, the average pain score was 6.71 in the gabapentinoid group, while the average pain score was 7.18 in the non-gabapentinoid group. There was no statistical significance between the groups (p = 0.28). There was no difference in response to treatment in gabapentinoid group (33.3%) when compared with non-gabapentinoid group (32.7%). We also failed to find any significant difference in daily opioid usage between the two groups. CONCLUSION: Gabapentinoids may not lead to reduction in pain or opioid consumption in patients with chronic spinal pain. A careful approach must be adopted while prescribing gabapentinoids in the chronic spinal pain patient population.

The Role of the Kynurenine Signaling Pathway in Different Chronic Pain Conditions and Potential Use of Therapeutic Agents.

Tryptophan (TRP) is an essential, aromatic amino acid catabolized by indoleamine 2,3-dioxygenase (IDO) and tryptophan 2,3-dioxygenase (TDO) enzymes into kynurenine. The IDO enzyme is expressed in peripheral tissues and the central nervous system. Another enzyme of interest in the kynurenine signaling pathway is kynurenine 3-monooxygenase (KMO). The purpose of this review is to discuss the role of TRP and the kynurenine signaling pathway in different chronic pain patients. The IDO-1, IDO-2, and KMO enzymes and the kynurenine metabolite have been shown to be involved in the pathogenesis of neuropathic pain and other painful conditions (migraine, cluster headache, etc.) as well as depressive behavior. We highlighted the analgesic potential of novel agents targeting the enzymes of the kynurenine signaling pathway to explore their efficacy in both future basic science and transitional studies. Upcoming studies conducted on animal models will need to take into consideration the differences in TRP metabolism between human and non-human species. Since chronic painful conditions and depression have common pathophysiological patterns, and the kynurenine signaling pathway is involved in both of them, future clinical studies should aim to have outcomes targeting not only pain, but also functionality, mood changes, and quality of life.

Neurogenic Claudication: a Review of Current Understanding and Treatment Options.

PURPOSE OF REVIEW: With an aging population and increased prevalence of the disease, we set out to evaluate the validity of current diagnostic criteria for neurogenic claudication as well as the efficacy of the treatment options for the main cause, lumbar spinal stenosis (LSS). RECENT FINDINGS: Epidural steroid injections (ESI) were most efficacious when the injectate is a steroid combined with lidocaine or lidocaine only. There are promising results regarding the efficacy of the minimally invasive lumbar decompression (MILD) procedure as well as interspinous process spacers (IPS) compared to surgical alternatives. Spinal cord stimulators are gaining ground as an effective alternative to surgery in patients with lumbar spinal stenosis that is not responsive to conservative measures or epidural injections. We found that there continues to be a lack of consensus on the diagnostic criteria, management, and treatment options for patients with LSS. The Delphi consensus is the most current recommendation to assist clinicians with making the diagnosis. Physical therapy, NSAIDs, gabapentin, and other conservative therapy measures are unproven in providing long-lasting relief. In patients with radicular symptoms, an ESI may be indicated when a combination of lidocaine with steroids is used or using lidocaine alone. In addition, there is not enough high-quality evidence to make a recommendation regarding the use of MILD versus interspinous spacers for neurogenic claudication. There remains a need for high-quality evidence regarding the efficacy of different conservative treatments, interventional procedures, and surgical outcomes in patients with neurogenic claudication in LSS.

An Association of Serotonin with Pain Disorders and Its Modulation by Estrogens.

Ovarian hormones play an important role in pain perception, and are responsible, at least in part, for the pain threshold differences between the sexes. Modulation of pain and its perception are mediated by neurochemical changes in several pathways, affecting both the central and peripheral nervous systems. One of the most studied neurotransmitters related to pain disorders is serotonin. Estrogen can modify serotonin synthesis and metabolism, promoting a general increase in its tonic effects. Studies evaluating the relationship between serotonin and disorders such as irritable bowel syndrome, fibromyalgia, migraine, and other types of headache suggest a clear impact of this neurotransmitter, thereby increasing the interest in serotonin as a possible future therapeutic target. This literature review describes the importance of substances such as serotonin and ovarian hormones in pain perception and illustrates the relationship between those two, and their direct influence on the presentation of the aforementioned pain-related conditions. Additionally, we review the pathways and receptors implicated in each disorder. Finally, the objective was to stimulate future pharmacological research to experimentally evaluate the potential of serotonin modulators and ovarian hormones as therapeutic agents to regulate pain in specific subpopulations.

The Role of Genetic Polymorphisms in Chronic Pain Patients.

It is estimated that the total annual financial cost for pain management in the U.S. exceeds 100 billion dollars. However, when indirect costs are included, such as functional disability and reduction in working hours, the cost can reach more than 300 billion dollars. In chronic pain patients, the role of pharmacogenetics is determined by genetic effects on various pain types, as well as the genetic effect on drug safety and efficacy. In this review article, we discuss genetic polymorphisms present in different types of chronic pain, such as fibromyalgia, low back pain, migraine, painful peripheral diabetic neuropathy and trigeminal neuralgia. Furthermore, we discuss the role of CYP450 enzymes involved in metabolism of drugs, which have been used for treatment of chronic pain (amitriptyline, duloxetine, opioids, etc.). We also discuss how pharmacogenetics can be applied towards improving drug efficacy, shortening the time required to achieve therapeutic outcomes, reducing risks of side effects, and reducing medical costs and reliance upon polypharmacy.

New Cancer Pain Treatment Options.

PURPOSE OF REVIEW: Cancer pain is often incapacitating and discouraging to patients; is demoralizing to family members and care takers; and is taxing and difficult to subdue for the pain specialists. The consequences of implementing suboptimal treatment are far-reaching; therefore, effective treatment methods are in a great demand. The face of cancer pain management has changed in considerable ways, and interventional procedures have become an integral part of providing multimodal analgesia in cancer pain treatment. The goals of this review are to draw attention to the critical role that regional anesthetic nerve blocks and interventional pain management techniques play in treating malignancy-related pain and emphasize the benefits provided by the aforementioned treatment strategies. RECENT FINDINGS: A large proportion of cancer patients continues to struggle with an inadequately treated pain despite a strict adherence to the WHO analgesic step ladder. The previous pain treatment algorithm has been modified to include peripheral neural blockade, neuro-destructive techniques, neuromodulatory device use, and intrathecal drug delivery systems. The accumulated evidence highlights the opioid-sparing qualities and other benefits afforded by these modalities: decreasing medication-induced side effects, reducing economic burden of poor analgesia, and overall improvement in quality of life of the patients afflicted with a painful neoplastic disease. The rising prevalence of cancer-related pain syndromes is paralleled by an unmatched growth of innovative treatment strategies. Modified WHO analgesic ladder represents one of the greatest paradigm shifts within the domain of oncologic pain treatment. The cancer patient population requires a prompt and liberal, albeit judicious, delivery of unorthodox pain treatment options freed from the rigid bonds of conventional guidelines and standard practices.

Can Chronic Pain Patients Be Adequately Treated Using Generic Pain Medications to the Exclusion of Brand-Name Ones?

According to the Food and Drug Administration (FDA) reports, approximately 8 in 10 prescriptions filled in the United States are for generic medications, with an expectation that this number will increase over the next few years. The impetus for this emphasis on generics is the cost disparity between them and brand-name products. The use of FDA-approved generic drugs saved 158 billion dollars in 2010 alone. In the current health care climate, there is continually increasing pressure for prescribers to write for generic alternative medications, occasionally at the expense of best clinical practices. This creates a conflict wherein both physicians and patients may find brand-name medications clinically superior but nevertheless choose generic ones. The issue of generic versus brand medications is a key component of the discussion of health payers, physicians and their patients. This review evaluates some of the important medications in the armamentarium of pain physicians that are frequently used in the management of chronic pain, and that are currently at the forefront of this issue, including Opana (oxymorphone; Endo Pharmaceuticals, Inc., Malvern, PA), Gralise (gabapentin; Depomed, Newark, CA), and Horizant (gabapentin enacarbil; XenoPort, Santa Clara, CA) that are each available in generic forms as well. We also discuss the use of Lyrica (pregabalin; Pfizer, New York, NY), which is currently unavailable as generic medication, and Cymbalta (duloxetine; Eli Lilly, Indianapolis, IN), which has been recently FDA approved to be available in a generic form. It is clear that the use of generic medications results in large financial savings for the cost of prescriptions on a national scale. However, cost-analysis is only part of the equation when treating chronic pain patients and undervalues the relationships of enhanced compliance due to single-daily dosing and stable and reliable pharmacokinetics associated with extended-duration preparations using either retentive technologies or delayed absorption strategies. Medications given to chronic pain patients should be individualized to best serve analgesic needs and assure patient safety primarily, based on high levels of scientific and economic evidence. Decisions regarding utilization should not be made based solely on limited or faulty assessments of cost-benefit analyses.

Ultrasonography Leads to Accurate Diagnosis and Management of Painful Acromioclavicular Joint Cyst.

BACKGROUND: Acromioclavicular joint (ACJ) cysts are uncommon causes of shoulder pain. Type 1 ACJ cysts are limited to the ACJ and form in the presence of intact rotator cuff musculature, while type 2 cysts form secondary to biomechanical instability following rotator cuff tear or rupture. CASE PRESENTATION: A 36-year-old overweight male with history of chronic left grade 2 (Rockwood classification) ACJ separation presented with intermittent pain at the distal superoanterior left clavicle. Physical examination revealed small step off at the ACJ and multiple subcutaneous cysts surrounding the ACJ. Ultrasound examination revealed a mild separation of the left ACJ, mild distension of the joint capsule, and a small, well-circumscribed, compressible hypo-echoic cyst overlying the clavicle. Palpation of the cyst against the clavicle reproduced the patient's symptoms of intermittent pain. He opted for ultrasound-guided aspiration and subsequently had full resolution of his symptoms. DISCUSSION: Musculoskeletal ultrasound is useful for diagnosis and management of refractory musculoskeletal conditions that are commonly misdiagnosed on physical examination and translucent to radiographic imaging. Musculoskeletal ultrasound allowed us to exclude rotator cuff pathology, identify ACJ cyst as the pain generator, classify it as a type 1 ACJ cyst, and aid in needle guidance for successful aspiration leading to full resolution of our patient's pain.

Celiac plexus block in the management of chronic abdominal pain.

Chronic abdominal pain is a devastating problem for patients and providers, due to the difficulty of effectively treating the entity. Both benign and malignant conditions can lead to chronic abdominal pain. Precision in diagnosis is required before effective treatment can be instituted. Celiac Plexus Block is an interventional technique utilized for diagnostic and therapeutic purposes in the treatment of abdominovisceral pain. The richly innervated plexus provides sensory input about pathologic processes in the liver, pancreas, spleen, omentum, alimentary tract to the mid-transverse colon, adrenal glands, and kidney. Chronic pancreatitis and chronic pain from pancreatic cancer have been treated with celiac plexus block to theoretically decrease the side effects of opioid medications and to enhance analgesia from medications. Historically, the block was performed by palpation and identification of bony and soft tissue anatomy; currently, various imaging modalities are at the disposal of the interventionalist for the treatment of pain. Fluoroscopy, computed tomography (CT) guidance and endoscopic ultrasound assistance may be utilized to aid the practitioner in performing the blockade of the celiac plexus. The choice of radiographic technology depends on the specialty of the interventionalist, with gastroenterologists favoring endoscopic ultrasound and interventional pain physicians and radiologists preferring CT guidance. A review is presented describing the indications, technical aspects, and agents utilized to block the celiac plexus in patients suffering from chronic abdominal pain.

A randomized, placebo-controlled trial of long-acting dexamethasone viscous gel delivered by transforaminal injection for lumbosacral radicular pain.

TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03372161.

Cervical epidural steroid injections for the treatment of cervical spinal (neck) pain.

Cervical epidural steroid injections (CESI) are an accepted treatment for neck pain with a radicular component, and may be accomplished by using either transforaminal (CTFESI) or interlaminar (CILESI) approaches. CESIs are routinely performed using real-time fluoroscopic-guidance in conjunction with the injection of water soluble, iodine-based contrast media to enhance visualization of intravascular injections. Digital subtraction angiography (DSA) imaging is an adjuvant to fluoroscopic methods for visualizing blood vessels while performing spinal injections. However, as with any neuraxial procedure, various complications associated with CESIs have been reported. Complications are directly associated with the technical procedures of CESIs. Particulate steroids may have a prolonged duration of action but non-particulate steroids are safer for CESIs. Blunt-beveled needles are less likely than sharp-beveled needles to penetrate blood vessels to cause bleeding complications during CTFESI procedures. Small doses of local anesthetics appear to be safe and assist in identifying intravascular injections previously overlooked by conventional techniques.

Thoracic epidural steroid injection for rib fracture pain.

Treatment for rib fracture pain can be broadly divided into pharmacologic approaches with oral and/or parenteral medication and interventional approaches utilizing neuraxial analgesia or peripheral nerve blocks to provide pain relief. Both approaches attempt to control nociceptive and neuropathic pain secondary to osseous injury and nerve insult, respectively. Success of treatment is ultimately measured by the ability of the selected modality to decrease pain, chest splinting, and to prevent sequelae of injury, such as pneumonia. Typically, opioids and NSAIDs are the drugs of first choice for acute pain because of ease of administration, immediate onset of action, and rapid titration to effect. In contrast, neuropathic pain medications have a slower onset of action and are more difficult to titrate to therapeutic effect. Interventional approaches include interpleural catheters, intercostal nerve blocks, paravertebral nerve blocks, and thoracic and lumbar epidural catheters. Each intervention has its own inherent advantages, disadvantages, and success rates. Rib fracture pain management practice is founded on the thoracic surgical and anesthesiology literature. Articles addressing rib fracture pain are relatively scarce in the pain medicine literature. As life expectancy increases, and as healthcare system modifications are implemented, pain medicine physicians may be consulted to treat increasing number of patients suffering rib fracture pain and may need to resort to novel therapeutic measures because of financial constraints imposed by those changes. Here we present the first published case series of thoracic epidural steroid injections used for management of rib fracture pain.

Overcoming clinical challenges of refractory neuropathic pain.

INTRODUCTION: Refractory neuropathic pain (ReNP), and its definition, is widely disputed among clinicians due in part to unclear diagnosing guidelines, overall duration of neuropathic pain, and the exhaustiveness of treatment options. Usually, ReNP is defined as chronic, intractable, and unresponsive neuropathic pain that has otherwise been untreatable. AREAS COVERED: In this narrative review, we discuss and summarize the effectiveness of prospective ReNP research conducted over the past 10 years. This research looks at pharmacological and interventional therapies in clinical trial settings. The pharmacological therapies discussed include the use of adjuvant treatments to improve the safety and efficacy of conventional approaches. Different modalities of administration, such as injection therapy and intrathecal drug delivery systems, provide targeted drug delivery. Interventional therapies such as neuromodulation, pulse radiofrequency, and nerve lesioning are more invasive; however, they are increasingly utilized in the field, as reflected in ongoing clinical trials. EXPERT OPINION: Based on the current data from RCTs and systematic reviews, it is clear that single drug therapy cannot be effective and has significant limitations. Transitioning to interventional modalities that showed more promising results sooner rather than later may be even more cost efficient than attempting different conservative treatments with a high failure rate.

Utility of Cervical Sympathetic Block in Treating Post-Traumatic Stress Disorder in Multiple Cohorts: A Retrospective Analysis.

BACKGROUND: Post-traumatic stress disorder (PTSD) is a prevalent and debilitating condition in the United States. Success rates for evidence-based therapies are inconsistent, and many suffer in silence due to the stigmata associated with seeking traditional mental health care. This has led clinicians to explore new therapeutic options, with cervical sympathetic blockade (CSB), performed at the stellate and/or superior cervical ganglion levels, recently emerging as a promising treatment option. Rapid therapeutic onset, improved compliance, and high clinical efficacy rates have made this an attractive approach for both providers and patients. However, to date, CSB as a treatment of PTSD has primarily been used in male patients with military-related trauma. OBJECTIVE: To evaluate the efficacy of CSB as a treatment option for PTSD in both genders and multiple etiologies of psychological trauma. STUDY DESIGN: Retrospective cohort study. SETTING: An established anesthesia pain clinic in Chicago, IL, USA. METHODS: Following retroactive IRB approval, 484 consecutive cases of patients diagnosed with PTSD and treated with CSB, performed by a single provider (December 2016 - February 2020) were analyzed. The primary outcome measurement was the PTSD Checklist Score version DSM IV (PCL-4). Patient demographic and clinical information collected included age, gender, type of trauma leading to PTSD, history of suicidal attempts, and psychiatric medication use. RESULTS: After exclusion of cases due to missing data points, 327 patients were included in the final statistical analysis, having completed both PCL-4 pre and post CSB, between 7- and 30-days post-intervention. The patient population included military men (n = 97), civilian men (n = 85), military women (n = 13) and civilian women (n = 132). We identified 21 types of self-reported trauma leading to PTSD. Average decrease in PCL score for men and women was 28.59 and 29.2, respectively. Statistical analysis of the male population with a military background showed a significantly greater change in corresponding PCL scores than civilians (PCL-M change = -31.83 vs PCL-C change = -24.89). Likewise, women who had a military background had a significantly greater reduction in PCL score than civilians (39.15 vs 28.23). Statistically significant improvements in PTSD symptoms were noted independent of the causative trauma type, gender, age greater than 20, previous suicide attempts, or use of prescription medications for PTSD. Among the 21 types of reported trauma, 19 types reached statistical significance. LIMITATIONS: Limitations include the limited scope of observation giving exclusive focus on pre- and post-PCL data, the limited duration of observation, the self-reported nature of the patient-provided data, and the provision of treatment by a single physician. CONCLUSION: CSB seems to be an effective treatment for PTSD symptoms irrespective of gender, trauma type, PTSD-related drug use, suicide attempt, or age.

No Differences in Pain Scores and Treatment Response in Patients from Different Socioeconomic Areas Within the City of Chicago.

BACKGROUND: It is well established that the experience of chronic pain significantly differs among ethnic-racial groups. There is mixed evidence to suggest that societal influences may contribute to pain prevalence among cultural groups and their treatment response. One possible explanation for differences in pain experience are the differences in socioeconomic status among patients with chronic pain. OBJECTIVE: To determine whether there is any difference in pain scores or treatment responses among patients with different socioeconomic status. STUDY DESIGN: Retrospective analysis. SETTING: Outpatient pain clinic. METHODS: After approval from the Advocate Healthcare Institutional Review Board, we included 1,149 patients treated for different chronic pain conditions who were followed for at least 12 months. Patients were stratified into quartiles determined by median income according to ZIP code. RESULTS: Of the sampled patients, 207 patients lived in ZIP codes with median incomes > $51,294; 515 in ZIP codes with median incomes between $40,083 and $51,294; 332 in ZIP  codes with median incomes between $30,625 and $40,083; and 95 in ZIP codes with median incomes < $30,625. Groups differed in age (P = 0.047), race (P < 0.001), body mass index (BMI) (P = 0.019), utilization of opioid medications (P = 0.011), morphine milligram equivalents (MME) on first visit (P = 0.036), and utilization of membrane stabilizers such as gabapentin (P = 0.019). There were no significant differences among groups in terms of gender (P = 0.531), type of pain experienced (P = 0.679), or time since pain onset (P = 0.174). Groups were treated similarly, with no statistically significant differences in the proportions of patients who had taken various nonopioid medications throughout their treatment course other than membrane stabilizers, the number of patients who received interventional pain management procedures, or MME at last visit. Average pretreatment numeric rating scale pain scores were not significantly different among quartiles (P = 0.079), posttreatment pain scores (P = 0.767), and subjective percent improvement (P = 0.434). LIMITATIONS: This is a single center study and may have limitations in extrapolating to the general population. CONCLUSION: The results of our study show that there are no differences in pain perception or treatment responses in patients from different socioeconomic statuses despite differences among groups in age, BMI, race, utilization of opioid medications, and MME at first visit. Patients at this pain practice appear to have been treated with similar modalities regardless of socioeconomic status.

Identifying molecular mechanisms of acute to chronic pain transition and potential drug targets.

INTRODUCTION: Chronic pain is pain that lasts more than the normal physiologic healing time at the time of initial insult. The transition from acute to chronic pain has been studied thoroughly. Understanding the mechanisms underlying chronic pain formation is essential for the development of novel treatments and therapeutics for chronic pain prevention. AREA COVERED: The transition from acute to chronic pain has been associated with the intracellular changes caused by repeated stimulus application, or neuronal priming, allowing for the chronicity of pain. Ongoing research studies have shown this priming to occur at various sites along the pathway for the neural transmission of pain. The purpose of this review is to not only elucidate the transition from acute to chronic pain and discuss current studies/trials related to this transition but also to highlight mechanisms involved in the process that could serve as potential targets for chronic pain prevention. EXPERT OPINION: We are providing an overview of novel treatment strategies for preventing the transition from acute to chronic pain. A multifaceted and multimodal approach that invokes multiple targets, at least one from each section (the periphery, the spinal cord, and the brain), would be the best option for tackling this problem.

Dehiscence and Deep Wound Infection After Spinal Cord Stimulator Implant Managed Without Explantation: A Case Report.

Deep infections of spinal cord stimulator devices usually result in explantation, as recommended by some professional societies. However, alternative options should be explored to avoid potential complications that are associated with explantation, and possibly additional procedures required in consideration of reimplantation. In this case, the patient presented with wound dehiscence after implantation. There was suspicion for deep wound infection based on a wound culture that was positive for Staphylococcus aureus, but no purulent material was noted on further inspection. The patient was treated with standard wound-care management and oral antibiotics without removing the device, and recovered while preserving the original system.