Chronic pain and the thoracic spine

Complex Regional Pain Syndrome (CRPS) is a challenging and often disabling condition marked by persistent pain, most commonly in a limb following injury or surgery. It presents with a wide array of symptoms, including intense pain, swelling, alterations in skin color and temperature, motor dysfunction, and trophic changes such as skin and tissue atrophy. While the precise cause of CRPS is not fully understood, it is thought to stem from abnormal nervous system activity, leading to heightened pain sensitivity and inflammatory responses. A thorough understanding of CRPS is essential for accurate diagnosis, effective treatment, and enhancing patients' quality of life.Although attempts have been made to distinguish between acute and chronic CRPS, there are currently no established diagnostic criteria specific to chronic CRPS in medical literature. This ASIPP guidance document offers updated, evidence-based recommendations for the diagnosis and management of Chronic Complex Regional Pain Syndrome (CRPS), with a primary focus on introducing novel, time-based diagnostic criteria specific to the chronic phase. These proposed criteria address significant gaps in the current literature, where existing standards, such as the Budapest Criteria, do not sufficiently differentiate between the acute and chronic stages of the condition. An expert panel convened by the American Society of Interventional Pain Physicians (ASIPP) conducted a comprehensive literature review and employed a structured consensus process to develop recommendations. Acknowledging that the clinical and pathological characteristics of CRPS change significantly beyond 12 months, the panel proposed chronic-specific diagnostic criteria based on disease duration, clinical history, physical examination findings, and optional diagnostic tests. These draft criteria were refined through multidisciplinary input and expert consensus. The diagnostic framework for chronic CRPS consists of four key components:General Criteria - Require fulfillment of the Budapest Criteria for at least 12 months, continued recognition of CRPS as a diagnosis of exclusion, and differentiation from generalized nociplastic pain syndromes.History-Based Criteria - Mandate the presence of at least three out of five specific historical features.Physical Examination Criteria - Include asymmetric limb findings, sensory disturbances, and musculoskeletal changes.Optional Diagnostic Testing - May involve assessments such as intraepidermal nerve fiber density (IENFD) and imaging evidence of regional bone demineralization.This framework builds upon the Budapest Criteria by incorporating time-dependent features of chronic CRPS, including musculoskeletal dystrophy, neurogenic inflammation, and sympathetic dysfunction. Emerging objective tools-such as quantitative sensory testing (QST), skin biopsy for IENFD, functional MRI, and serum biomarkers of neuroinflammation-may further support diagnosis in complex or uncertain cases.Treatment recommendations highlight a multimodal strategy that integrates physical rehabilitation, pharmacologic management of neuropathic pain, sympathetic nerve blocks, and advanced neuromodulation. Emphasis is placed on individualized care pathways tailored to disease stage and patient-specific characteristics. This article presents the first structured, time-sensitive diagnostic criteria for chronic CRPS, aimed at improving diagnostic accuracy and informing treatment strategies. Adoption of these criteria may enhance clinical outcomes and promote further research into the natural history and pathophysiology of CRPS progression.

Patients with complex regional pain syndrome suffer from chronic neuropathic pain and also show a decrease in sensorimotor performance associated with characteristic central and peripheral neural system parameters. In the brain imaging domain, these comprise altered functional sensorimotor representation for the affected hand side. With regard to neurophysiology, a decrease in intracortical inhibition for the sensorimotor cortex contralateral to the affected hand has been repetitively verified, which might be related to increased primary somatosensory cortex functional activation for the affected limb. Rare longitudinal intervention studies in randomized controlled trials have demonstrated that a decrease in primary somatosensory cortex functional MRI activation coincided with pain relief and recovery in sensorimotor performance. By applying a randomized wait-list control crossover study design, we tested possible associations of clinical, imaging and neurophysiology parameters in 21 patients with complex regional pain syndrome in the chronic stage (>6 months). In more detail, we applied graded motor imagery over 6 weeks to relieve movement pain of the affected upper limb. First, baseline parameters were tested between the affected and the non-affected upper limb side and age-matched healthy controls. Second, longitudinal changes in clinical and testing parameters were associated with neurophysiological and imaging parameters. During baseline short intracortical inhibition, as assessed with transcranial magnetic stimulation, was decreased only for hand muscles of the affected hand side. During movement of the affected limb, primary somatosensory cortex functional MRI activation was increased. Hand representation area size for somatosensory stimulation in functional MRI was smaller on the affected side with longer disease duration. Graded motor imagery intervention but not waiting, resulted in a decrease of movement pain. An increase of somatosensory hand representation size over graded motor imagery intervention was related to movement pain relief. Over graded motor imagery intervention, pathological parameters like the increased primary somatosensory cortex activation during fist movement or decreased short intracortical inhibition were modified in the same way as movement pain and hand performance improved. No such changes were observed during the waiting period. Overall, we demonstrated characteristic changes in clinical, behaviour and neuropathology parameters applying graded motor imagery in patients with upper limb complex regional pain syndrome, which casts light on the effects of graded motor imagery intervention on biomarkers for chronic neuropathic pain.

Graded motor imagery (GMI) shows promising results for patients with complex regional pain syndrome (CRPS). In a case with chronic unilateral CRPS type I, we applied GMI for 6 weeks and recorded clinical parameters and cerebral activation using functional magnetic resonance imaging (fMRI; pre-GMI, after each GMI block, and after 6 mo). Changes in fMRI activity were mapped during movement execution in areas associated with pain processing. A healthy participant served as a control for habituation effects. Pain intensity decreased over the course of GMI, and relief was maintained at follow-up. fMRI during movement execution revealed marked changes in S1 and S2 (areas of discriminative pain processing), which seemed to be associated with pain reduction, but none in the anterior insula and the anterior cingulate cortex (areas of affective pain processing). After mental rotation training, the activation intensity of the posterior parietal cortex was reduced to one third. Our case report develops a design capable of differentiating cerebral changes associated with behavioral therapy of CRPS type I study.

Pain is defined by the International Association for the Study of Pain as ‘an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage’. Acute pain is predictable following surgical intervention; chronic pain is less so. Chronic pain, persisting for longer than 3 months, or beyond expected wound healing, is a worldwide problem affecting around 20% of the adult population. Chronic postsurgical pain is multifactorial, although it often involves some form of nerve damage, with clinical signs consistent with this. Neuropathic pain may have a greater impact on quality of life than other chronic pain syndromes. It is important, therefore, to identify neuropathic pain as early as possible, in order to initiate appropriate management and reduce longer-term impact. This chapter focuses on two types of neuropathic pain: chronic postsurgical pain and complex regional pain syndrome.

Therapeutic neuroscience education (TNE) aims to alter a patient's thoughts and beliefs about pain and has shown efficacy in treating chronic pain. To date, TNE sessions mainly consist of one-on-one verbal communication. This approach limits availability of TNE to pain patients in remote areas. A 32-year-old patient with chronic low back pain (CLBP) who underwent surgery for thoracic outlet syndrome (TOS) attended a single clinic one-on-one TNE session followed by TNE via electronic mail (e-mail), pacing and graded exposure over a 4-month period. A physical examination, Numeric Rating Scale (NRS), Oswestry Disability Index (ODI), the Disabilities of Arm, Shoulder and Hand (DASH), and Fear-Avoidance Beliefs Questionnaire (FABQ) were assessed during her initial physical therapy visit as well as 1 and 4 months later. Pre-TNE, the patient reported: NPRS (arm) = 7/10; NPRS (leg) = 4/10; ODI = 10.0%; DASH = 36.7%; FABQ-W = 24; and FABQ-PA = 17. After 5 e-mail sessions all outcome measures improved, most noticeably NRS (arm) = 2/10; NRS (leg) = 0/10; DASH = 16.7%; FABQ-W = 8; and FABQ-PA = 7. TNE can potentially be delivered to suffering pain patients in remote areas or to individuals who have time and financial constraints, and likely at a significant reduced cost via e-mail.

Secular Mindfulness-Based Interventions: Efficacy and Neurobiology.

Background: Stellate Ganglion Blocks (SGB) involve injecting local anesthetic near the stellate ganglion, which includes the C6, C7, and T1 ganglia. This procedure induces a sympathetic blockade and has been employed to address various conditions, such as post-traumatic stress disorder (PTSD), ventricular arrhythmias, and chronic pain syndromes like complex regional pain syndrome (CRPS). Central to this case series is the exploration of SGB as a unified treatment for PTSD and chronic low back pain-two conditions linked by central sensitization. Case Series Overview: The study presents three female veterans with histories of PTSD, chronic low back pain, and myofascial pain. These patients had not responded to conventional treatments, including medications and interventional procedures. They underwent SGB with a combination of 10 mg preservative-free dexamethasone sodium phosphate, 4 mL preservative-free lidocaine 2% with epinephrine, and 1 mL preservative-free bupivacaine 0.25%. The procedure was well tolerated without adverse effects. All three patients experienced significant improvements. The first and third patients reported reductions in PTSD symptoms, low back pain, and myofascial pain. The second patient experienced relief from PTSD symptoms and prolonged reduction in myofascial pain. This case series is the first to document SGB's effectiveness in treating chronic low back pain alongside PTSD. Conclusions: The findings suggest that SGB could be an effective therapy for chronic overlapping conditions like PTSD, chronic low back pain, and myofascial pain, all of which share central sensitization mechanisms. The literature supports the notion that these conditions involve both physical and psychiatric components potentially responsive to SGB. By targeting sympathetic hyperactivity and reducing norepinephrine levels, SGB may alleviate symptoms across these interconnected syndromes. This case series highlights the potential of SGB as a novel approach for managing comorbid PTSD and chronic pain conditions. Further research is warranted to confirm its efficacy and explore its broader applications in treating central sensitization-related disorders and chronic overlapping pain conditions (COPC), potentially responsive to sympathetic blockade.

To systematically identify and summarize possible subtypes of complex regional pain syndrome (CRPS), we searched MEDLINE, Embase, Cochrane, Scopus, and Web of Science for original studies reporting or investigating at least one subtype within a group of patients with CRPS. The search retrieved 4239 potentially relevant references. Twenty-five studies met our inclusion criteria and were included in the analysis. Complex regional pain syndrome phenotypes were investigated based on the following variables: clinical presentation/sensory disturbances, dystonia, skin temperature, disease duration, onset type, CRPS outcome, and neuropsychological test performance. Support was found for the following CRPS subtypes: CRPS type I, CRPS type II, acute CRPS, chronic CRPS, centralized CRPS, cold CRPS, warm CRPS, inflammatory CRPS, dystonic CRPS, nondystonic CRPS, familial CRPS, and nonfamilial CRPS. It is unclear whether these are distinct or overlapping subtypes. The results of this comprehensive review can facilitate the formulation of well-defined CRPS subtypes based on presumed underlying mechanisms. Our findings provide a foundation for establishing and defining clinically meaningful CRPS subtypes, with the ultimate goal of developing targeted and enhanced treatments for CRPS.

Although the association of chronic pain (CP) with a poor work-life balance has been well studied, the interaction effect of multiple pain sites on work-life balance is unknown. To evaluate the most prevalent CP site among healthcare workers, the demographic characteristics of the individuals with the predominant pain type, and to assess the interaction of multiple pain sites on work-life balance. Using data from the National Health Interview Survey, 2,458 healthcare works were identified for this study. The independent variables were chronic low back and hip pain. The dependent variables were (1) if pain affected their family or significant other, (2) if pain limited their life or work activities, and (3) Usually working >35 hours/week. Multiple logistic regression and an interaction analysis were used to analyze the impact of different pain sites on work-life balance. Among healthcare workers, chronic low back pain was more prevalent than chronic hip pain (69.4% vs 61.4%, p-value<0.001). Respondents with chronic low back pain were mostly 40 - 64 years of age (49.6%), females (71.2%), white (77.6%), married (55.5%), had no college degree (85.4%), earn greater than $75,000 (50.0%). In the interaction analysis, in the presence of chronic hip pain, those with chronic low back pain had an AOR of 2.20 (1.05 - 4.64), p-value 0.038 of chronic low back pain affecting their family and significant others, and an AOR of 2.18 (1.17- 4.05), p-value 0.014 of chronic low back pain affecting their life or work. Chronic low back pain was more prevalent than chronic hip pain among healthcare workers. Together both pain sites had a significant impact on the work-life balance of this population. Further studies should assess other dimensions of work-life balance and chronic pain.

Chronic low back pain (CLBP) significantly impairs quality of life and increases mortality among older adults, making its effective management essential for healthy aging. This quasi-randomized trial compared Pain Neuroscience Education emphasizing physical activity (PNE-PA) with traditional biomechanical treatments (BM) in older women with CLBP over 12 weeks. Community-dwelling women aged 65–90 years with CLBP were assigned to either group based on recruitment timing, using a double-blinded design. PNE-PA aimed to reduce pain-related fear by educating patients about pain neuroscience and encouraging physical activity. Outcomes included physical function, pain intensity, self-reported disability and psychological factors. Analyses used intention-to-treat and bootstrap resampling methods. Between-group differences were assessed using mean differences, 95% confidence intervals (CI), and Cohen’s d. The PNE-PA group (n = 24) showed significantly greater improvements than the BM group (n = 18) in Chair Stand Test (95% CI: 1.53 to 7.76, d = 0.88), step count (95% CI: 475.97 to 2550.42, d = 0.87), pain catastrophizing (95% CI: -10.64 to -1.95, d = -0.87), and fear-avoidance beliefs (95% CI: -7.40 to -0.14, d = -0.65). These findings suggest that Pain Neuroscience Education emphasizing physical activity was associated with better physical and psychological outcomes among older women with chronic low back pain.

Management of long-term complex regional pain syndrome with allodynia: A case report

Complex regional pain syndrome (CRPS) is a debilitating chronic pain condition that may develop after fractures, surgery, or soft tissue trauma. It is characterized by pain disproportionate to the initial injury, often accompanied by sensory, motor, autonomic, and trophic changes. Despite extensive research, pathophysiology remains unclear, and treatment approaches are varied, with inconsistent supporting evidence. Given its complexity and the potential for chronic disability, identifying effective therapies remains a clinical priority.This review systematically evaluated the analgesic efficacy of pharmacological and non-pharmacological therapies for CRPS, based on randomized controlled trials (RCTs) published between 2003 and 2025. The protocol was developed previously and registered in PROSPERO (CRD420251026503).A structured literature search using a PICO (Population, Intervention, Comparator, Outcome) framework was conducted across MEDLINE, PubMed, and the Cochrane Library. Search terms included “Complex Regional Pain Syndrome,” its earlier term “Reflex Sympathetic Dystrophy,” and intervention-specific keywords. Included were English-language RCTs in adults with clinically diagnosed CRPS (type I or II), assessing pain reduction as the primary outcome and function, quality of life, and pain medication use as secondary outcomes. Two reviewers independently screened and extracted studies. Risk of bias was assessed using the Cochrane Risk of Bias (ROB) 2. Publication bias was evaluated using funnel plots of standard errors and effect sizes.In total, 45 RCTs met the inclusion criteria and included 2,125 patients. Among pharmacological interventions, bisphosphonates showed consistent and significant pain reduction over six months. Intravenous ketamine demonstrated strong short-term analgesia, though findings were limited by small samples, variable protocols, and lack of long-term data. Combinations of local anesthetics and other medications (e.g., lidocaine with citalopram or parecoxib) were especially effective in acute CRPS. Steroid treatments (oral or regional) offered short-term pain relief and functional improvement, particularly in early or post-stroke CRPS.Non-pharmacological therapies also showed promise in reducing CRPS pain. Mirror therapy (MT) and graded motor imagery (GMI) consistently improved pain and motor function, especially when applied early. Pain exposure physical therapy (PEPT) improved range of motion but had a limited impact on overall functional outcomes. Neuromodulation methods, including spinal cord stimulation (SCS), dorsal root ganglion (DRG) stimulation, and transcutaneous electrical nerve stimulation (TENS), provided durable pain relief in select patients but were technically complex and associated with complications, particularly with SCS.In conclusion, CRPS remains a complex and difficult-to-treat condition, with substantial variability in treatment response. RCT evidence supports the use of bisphosphonates, ketamine, and early use of mirror or motor imagery therapies. Neuromodulation via electrical stimulation may benefit select cases but carries procedural risks. Physiotherapeutic strategies offer low-cost, low-risk benefits, especially when started early or combined with pharmacotherapy. However, many studies were limited by small size, short follow-up, or methodological flaws. There is an urgent need for large, high-quality, and mechanistically informed RCTs to guide long-term CRPS management.

BACKGROUND: Graded motor imagery (GMI) is a treatment for patients with chronic pain. GMI was initially developed for pain conditions of the extremities (eg, hand, elbow), but has limited application for chronic neck pain. CASE PRESENTATION: A 40-year-old female with an 11-year history of right-sided neck pain and migraines was referred to physical therapy. She reported ongoing symptoms despite engaging with various interventions over an 11-year period. OUTCOME AND FOLLOW-UP: A 4-stage modified GMI program, as part of a multimodal treatment program, resulted in a reduced Neck Disability Index score from 17/50 to 6/50, increased average Patient-Specific Functional Scale score on 5 items from 4.4 to 7.6, and significant reduction in pain and migraine frequency and intensity. DISCUSSION: A multimodal treatment program that included a modified-GMI program yielded clinical benefits in a patient with chronic nonspecific neck pain. JOSPT Cases 2025;5(2):96-102. Epub 27 February 2025. doi:10.2519/josptcases.2025.0083

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BackgroundAttentional distraction from pain has been shown to be largely ineffective for obtaining a hypoalgesic effect in patients with chronic pain when compared to a control condition. It has been hypothesized that this may be due to the non-engaging types of distraction that have been used so far. Moreover, it is suggested that the hypoalgesic effects of distraction may be attenuated by pain-related cognitions and emotions, as they may increase the attention to pain.MethodsIn this randomized controlled trial, patients with chronic nonspecific low back pain in the intervention group (n = 42) performed a single exercise session with nonimmersive VR games, while those in the control group (n = 42) performed the same exercises without VR games. We investigated whether VR distraction had a hypoalgesic effect during and immediately after the exercises, and whether it reduced the time spent thinking of pain during the exercises. We further explored whether pain-related fear, pain catastrophizing and baseline pain intensity moderated the effects of VR distraction.ResultsVR distraction had a hypoalgesic effect during (Cohen’s d = 1.29) and immediately after (Cohen’s d = 0.85) the exercises, and it also reduced the time spent thinking of pain (Cohen’s d = 1.31). Preliminary exploratory analyses showed that pain-related fear, pain catastrophizing and baseline pain intensity did not moderate the effects of VR distraction.ConclusionsLarge effect sizes of VR distraction induced hypoalgesia were observed. This suggests that nonimmersive VR games can be used when it is deemed important to reduce the pain during exercises in patients with chronic nonspecific low back pain.Trial registrationNCT02679300. This trial was registered on 10 February 2016.