Complex regional pain syndrome should be aggressively treated as soon as it is diagnosed.

COMPLEX regional pain syndrome (CRPS), previously known as reflex sympathetic dystrophy (RSD), is used to describe a syndrome of pain and sudomotor or vasomotor instability. This pain syndrome usually has an initiating noxious event in the periphery, is not limited to the distribution of a single nerve, and is disproportionate to the inciting event. The Consensus Conference of the International Association for the Study of Pain has subclassified CRPS into two forms: CRPS I (formerly RSD) and CRPS II (formerly causalgia). According to the International Association for the Study of Pain, the diagnosis of CRPS I requires (1) continuing pain, allodynia, or hyperalgesia disproportionate to the injury; (2) evidence at some time of edema, changes in skin blood flow, or abnormal sudomotor activity in the region of pain; and (3) no other conditions that would otherwise account for the degree of pain and dysfunction. Motor disturbances and trophic changes, such as altered nail and hair growth, may be observed in some cases. CRPS II is a pain syndrome that starts after a nerve injury and is not necessarily limited to the distribution of the injured nerve. The diagnostic criteria are the same as those of CRPS I. Patients with CRPS I or CRPS II can have sympathetically maintained pain or sympathetically independent pain. Sympathetically maintained pain, a term introduced in 1986 by Roberts, is pathologic pain that is supported by sympathetic efferent activity, circulating catecholamines, and/or increased sensitivity of -adrenergic receptors. Sympathetically maintained pain is identified by the ability to lessen the pain by sympatholytic blocks or interventions. Sympathetically independent pain has components of pain from sources other than sympathetic innervation and is believed to be most commonly observed in advanced cases of CRPS that do not respond to sympathetic blocks. Patients with CRPS may present with components of only sympathetically maintained pain or sympathetically independent pain or, more commonly, a combination of pain from each. Despite increasing research interest, little is known regarding which patients are at increased risk for development of postoperative CRPS and what the optimal perioperative treatment strategy is for those patients undergoing surgery who have a previous history of CRPS. This review outlines the surgical procedures that are believed to increase risk for development of CRPS and describes pharmacologic and regional analgesic techniques that may be of benefit for preventing the development of CRPS after surgery.

Complex regional pain syndrome (CRPS) is a painful and disabling condition that usually manifests in response to trauma or surgery. When it occurs, it is associated with significant pain and disability. It is thought to arise and persist as a consequence of a maladaptive pro-inflammatory response and disturbances in sympathetically-mediated vasomotor control, together with maladaptive peripheral and central neuronal plasticity. CRPS can be classified into two types: type I (CRPS I) in which a specific nerve lesion has not been identified, and type II (CRPS II) where there is an identifiable nerve lesion. Guidelines recommend the inclusion of a variety of physiotherapy interventions as part of the multimodal treatment of people with CRPS, although their effectiveness is not known. To determine the effectiveness of physiotherapy interventions for treating the pain and disability associated with CRPS types I and II. We searched the following databases from inception up to 12 February 2015: CENTRAL (the Cochrane Library), MEDLINE, EMBASE, CINAHL, PsycINFO, LILACS, PEDro, Web of Science, DARE and Health Technology Assessments, without language restrictions, for randomised controlled trials (RCTs) of physiotherapy interventions for treating pain and disability in people CRPS. We also searched additional online sources for unpublished trials and trials in progress. We included RCTs of physiotherapy interventions (including manual therapy, therapeutic exercise, electrotherapy, physiotherapist-administered education and cortically directed sensory-motor rehabilitation strategies) employed in either a stand-alone fashion or in combination, compared with placebo, no treatment, another intervention or usual care, or of varying physiotherapy interventions compared with each other in adults with CRPS I and II. Our primary outcomes of interest were patient-centred outcomes of pain intensity and functional disability. Two review authors independently evaluated those studies identified through the electronic searches for eligibility and subsequently extracted all relevant data from the included RCTs. Two review authors independently performed 'Risk of bias' assessments and rated the quality of the body of evidence for the main outcomes using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. We included 18 RCTs (739 participants) that tested the effectiveness of a broad range of physiotherapy-based interventions. Overall, there was a paucity of high quality evidence concerning physiotherapy treatment for pain and disability in people with CRPS I. Most included trials were at 'high' risk of bias (15 trials) and the remainder were at 'unclear' risk of bias (three trials). The quality of the evidence was very low or low for all comparisons, according to the GRADE approach.We found very low quality evidence that graded motor imagery (GMI; two trials, 49 participants) may be useful for improving pain (0 to 100 VAS) (mean difference (MD) -21.00, 95% CI -31.17 to -10.83) and functional disability (11-point numerical rating scale) (MD 2.30, 95% CI 1.12 to 3.48), at long-term (six months) follow-up, in people with CRPS I compared to usual care plus physiotherapy; very low quality evidence that multimodal physiotherapy (one trial, 135 participants) may be useful for improving 'impairment' at long-term (12 month) follow-up compared to a minimal 'social work' intervention; and very low quality evidence that mirror therapy (two trials, 72 participants) provides clinically meaningful improvements in pain (0 to 10 VAS) (MD 3.4, 95% CI -4.71 to -2.09) and function (0 to 5 functional ability subscale of the Wolf Motor Function Test) (MD -2.3, 95% CI -2.88 to -1.72) at long-term (six month) follow-up in people with CRPS I post stroke compared to placebo (covered mirror).There was low to very low quality evidence that tactile discrimination training, stellate ganglion block via ultrasound and pulsed electromagnetic field therapy compared to placebo, and manual lymphatic drainage combined with and compared to either anti-inflammatories and physical therapy or exercise are not effective for treating pain in the short-term in people with CRPS I. Laser therapy may provide small clinically insignificant, short-term, improvements in pain compared to interferential current therapy in people with CRPS I.Adverse events were only rarely reported in the included trials. No trials including participants with CRPS II met the inclusion criteria of this review. The best available data show that GMI and mirror therapy may provide clinically meaningful improvements in pain and function in people with CRPS I although the quality of the supporting evidence is very low. Evidence of the effectiveness of multimodal physiotherapy, electrotherapy and manual lymphatic drainage for treating people with CRPS types I and II is generally absent or unclear. Large scale, high quality RCTs are required to test the effectiveness of physiotherapy-based interventions for treating pain and disability of people with CRPS I and II. Implications for clinical practice and future research are considered.

Background: Sympathetic block is commonly performed in clinical practice for management of intractable pain conditions. However, stellate ganglion block (SGB) alone often does not achieve sufficient sympatholysis of the upper extremity. The paravertebral space continues up to the cervical sympathetic chain and includes the stellate ganglion. We compared the sympatholytic and analgesic effect of paravertebral block performed at the T2 level (T2 PVB) with that of SGB in patients with complex regional pain syndrome (CRPS) of the upper extremity. Objectives: The aim of this study was to compare the sympatholytic property of T2 PVB with that of the conventional SGB in patients with CRPS of the upper extremity. Study Design: Prospective, randomized cross-over trial. Setting: University hospital pain center in Korea. Methods: Fifteen patients with upper extremity CRPS were randomly assigned to 1 of 2 intervention methods (SGB or T2 PVB). After effects of the first block receded, the patients were crossed over to the second procedure. A difference in temperature increase between the treated side and the opposite side (ΔT) ≥ 1.5°C was considered as a successful primary outcome. Rate of successful primary outcome, degree of pain reduction, duration of effect, and patient satisfaction scores were compared between the 2 intervention methods. Results: Rate of successful primary outcome (ΔT ≥ 1.5°C) was significantly higher in the T2 PVB cases than in the SGB cases (80.0% vs. 20.0%; P = 0.003). Numeric Rating Scale scores after the procedure were significantly lower in the T2 PVB group. Patient satisfaction scores were significantly higher, and the duration of the block was significantly longer in the T2 PVB cases than in the SGB cases. Limitations: The relatively small sample size from a single center, and the lack of standardization of the injected volume of T2 PVB and SGB were limitations. Conclusions: T2 PVB showed superior sympatholytic effect than SGB; other clinical outcomes were also better with T2 PVB than with SGB. T2 PVB can be a useful option for producing sympatholytic and analgesic effect in patients with CRPS of the upper extremity. Key words: Sympathetic block, Complex Regional Pain Syndrome, paravertebral block, stellate ganglion block

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.

Localized hypertrichosis after index finger revascularization and complex regional pain syndrome.

Complex regional pain syndrome (CRPS) is frequently diagnosed in patients recovering from surgery or injury. The symptoms and signs included in consensus diagnostic criteria for CRPS are expected after injury. Categorizing symptoms and signs that occur on a continuum as disproportionate or not is subjective and prone to bias. Psychiatrists and psychologists do not diagnose CRPS and instead measure and treat anxiety and catastrophic thinking on its continuum. Given the expected variation in subjective diagnoses such as CRPS, this study addresses factors associated with use of this diagnosis and how it influences care. (1) Among patients recovering from fracture of the distal radius, what factors are associated with the diagnosis of CRPS? (2) Are patients diagnosed with CRPS after distal radius fractures, as opposed to those without CRPS, more likely to have a bone scan, stellate ganglion block, therapy, or subsequent surgery? Using the Truven database, we identified 59,765 patients treated for a distal radius fracture from 2012 to 2014, of whom 114 (0.19%) were diagnosed with CRPS. The Truven Health MarketScan database is an administrative claims data set of commercially insured patients and this analysis only included patients with complete enrollment from 2012 through 2014. Bivariate analyses sought differences between patients diagnosed with and patients not diagnosed with CRPS. All factors with p < 0.05 were included in a multivariable logistic regression model. The covariates older age (odds ratio [OR], 1.029; 95% confidence interval [CI], 1.011-1.048; p = 0.002), gender (women at greater risk, OR, 3.86; CI, 1.99-7.49; p < 0.001), concomitant fracture of the distal ulna (OR, 1.54; CI, 1.05-2.23; p = 0.029), open fracture (OR, 0.414; CI, 0.192-0.895; p = 0.025), and comorbid fibromyalgia (OR, 16.0; CI, 4.92-51.8; p < 0.001) were independently associated with a diagnosis of CRPS among patients recovering from a fracture of the distal radius. Patients diagnosed with CRPS are more likely than other patients with a distal radius fracture to have had a bone scan (OR, 66.0; CI, 8.19-532; p < 0.001), physical or occupational therapy (OR, 3.89; CI, 2.68-5.67; p < 0.001), and subsequent wrist surgery (OR, 2.52; CI, 1.65-3.84; p < 0.001). No one had a stellate ganglion injection. We found that a coded diagnosis of CPRS is uncommonly applied to patients on the higher range of pain, stiffness, and limitations after fracture of the distal radius-most commonly in women and in association with another nonspecific, objectively unverifiable diagnosis (fibromyalgia)-and that this label may lead to more testing and invasive treatment. Future research should address the utility and value of diagnoses that create subjective categories for aspects of human illness that occur on a continuum. Level III, prognostic study.

Complex Regional Pain Syndrome (CRPS) is a Neuropathic Pain (Neu-P) Syndrome that lacks clear comprehension and could potentially have diverse causal origins. The occurrence of this syndrome following trauma is frequent, as reported in the literature. We report a patient with a history of spinal cord injury at C6/7 &amp; C7/T1 levels in RTA, who underwent cervical spine fixation surgery, and developed hyperalgesia, allodynia, edema, and color changes in the upper limb 3-4 weeks after surgery. A multimodal therapeutic technique was implemented in the present study, incorporating a stellate ganglion block intervention, which resulted in notable benefits. These benefits included a reduction in pain scores and an improvement in mobility of the affected limb.

We read with interest the review article by Dr. Reuben entitled “Preventing the Development of Complex Regional Pain Syndrome after Surgery.”1The author mentioned that in his practice, he administers a stellate ganglion block to patients with a history of complex regional pain syndrome (CRPS) undergoing upper extremity surgical procedures in an effort to prevent its recurrence. Although the literature supports this practice, the efficacy of a stellate ganglion block has broader applications to patients without a history of CRPS. No study has examined its use in the acute postoperative setting. Nevertheless, we report the first case using a stellate ganglion block to treat acute postoperative pain successfully in a patient without a history of CRPS who underwent an open reduction and internal fixation of his left humerus.A 46-yr-old, 70-kg male with a medical history significant for recent cocaine abuse underwent general anesthesia for an open reduction and internal fixation of a left humerus fracture. The 3-h intraoperative course was uneventful during a 3% desflurane in 50% nitrous and oxygen anesthetic. Fentanyl, 500 μg, and 5 mg morphine were also given intraoperatively. In the postanesthesia care unit, an additional 20 mg morphine was titrated for pain relief, although to no avail: The patient’s pain score remained 10 out of 10. On further evaluation, his left upper extremity appeared cold, clammy, and edematous, whereas the pain characteristic was described as burning.After informed consent, a left stellate ganglion block was performed using 10 ml bupivacaine, 0.25%, with a sterile technique. Pain relief (0 out of 10) was achieved 5 min after injection. Evidence of successful blockade included ptosis and miosis, temperature increase in the ipsilateral extremity, and an increase in perfusion index.Numerous publications in the literature support the use of a stellate ganglion block for chronic sympathetically mediated pain; however, to the best of our knowledge, we report the first case in which a stellate ganglion block was used in the acute postoperative setting. Furthermore, the success of the block in absence of a history of CRPS illustrates primary prevention—interventions to prevent a disease from occurring. Activation of the sympathetic pain pathways could have taken place before the patient’s operating room visit or even intraoperatively. Nevertheless, the challenge is to recognize the clinical symptoms that differentiate acute CRPS from postsurgical pain, despite the close resemblance.2Further review of the case revealed that the patient’s fracture was a week old, which may have contributed to an alteration of central nociceptive processing pathways, thus increasing his risk for development of postsurgical CRPS.3Overall, we share the same enthusiasm of Dr. Ruben on regional anesthetic techniques to prevent the occurrence of CRPS. In our clinical practice, it is not only important to focus on CRPS prevention, but also to understand the pathophysiology so that we know which patients are at greatest risk.* Harbor-UCLA Medical Center, Torrance, California. ckakazu@hotmail.com

Baystate Medical Center and the Tufts University School of Medicine, Springfield, Massachusetts. scott.reuben@bhs.orgI appreciate the comments by Drs. Kakazu and Julka. Although the role of the sympathetic nervous system in certain chronic pain states, including complex regional pain syndrome (CRPS), has been well documented,1,2its role in acute pain and inflammation is still controversial.3,4A coupling between the sensory afferent and sympathetic efferent system after peripheral nerve lesions has been previously described as a causative mechanism for neuropathic pain, including CRPS.1,2However, the role of the sympathetic nervous system in acute pain still must be elucidated. The sympathetic nervous system may influence the nociceptive response to acute tissue injury in two ways.4First, there is a potentiation of the chemical mediator cascade after trauma as well as augmentation of sensitization to substance P. Second, norepinephrine and α2agonism in the dorsal horn neurons and in the locus ceruleus in the medulla play a major role in the descending medullospinal inhibition of nociception. Experimental studies in rats indicate that sympathetic postganglionic neurons may be involved in the generation of pain, hyperalgesia, and inflammation after tissue damage or trauma.5,6Sensitization of nociceptive afferent fibers in the knee joints of rats involves a cascade of events in which the mast cell and the sympathetic terminal are sequentially activated, resulting in plasma extravasation in the synovium.5,6Further, adrenal medullary-derived epinephrine can exacerbate and surgical or pharmacologic sympathectomy can decrease the severity of experimental arthritis.5Although these behavioral studies in rats point to a potential role of the sympathetic nervous system in acute inflammatory pain, neurophysiologic studies of nociceptors in rats and psychophysical studies in humans have failed to provide confirmatory evidence for the role of sympathetic efferents in inflammatory pain and hyperalgesia.3The use of a stellate ganglion block for acute postoperative pain as described by Drs. Kakazu and Julka is intriguing. I agree with the authors that because this patient sustained his fracture 1 week before surgical correction, prolonged sensitization and alteration of nociceptive afferent pathways may have increased the risk for the development of postsurgical CRPS. However, the authors did not report whether this patient had any clinical symptoms consistent with CRPS before surgical intervention. Perhaps the surgical intervention exacerbated an underlying disease process that may have been initiated before surgery. Interestingly, since the success of our original report on the efficacy of stellate ganglion blocks for CRPS patients undergoing surgery,7many of our surgeons now request that we routinely perform this sympathetic block for non-CRPS patients who are undergoing surgical procedures and are at increased risk for development of this disease. Although stellate ganglion block may be effective for treating acute postoperative neuropathic pain, it may also be useful in the management of acute nociceptive pain. Matsuura et al. 8describe the efficacy of stellate ganglion block in 29 patients undergoing ocular surgery. These authors report a significant reduction in postoperative pain and nonsteroidal antiinflammatory drugs with the use of stellate ganglion block. These case studies highlight the importance of moving from symptom control toward a mechanism-specific pharmacologic management of postoperative pain.9We have only begun to identify the multiple neurobiologic mechanisms responsible for different pain states. We hope to be able to develop diagnostic tools that will allow us to identify these mechanisms in individual patients and target them with appropriate analgesic interventions. Future research is needed in defining the clinical significance of the interaction of the sympathetic nervous system and the somatic afferent system in the development of postoperative pain. At that time, we may have available not only the resources for eliminating acute pain but also the tools necessary for preventing the occurrence of chronic postsurgical pain.Baystate Medical Center and the Tufts University School of Medicine, Springfield, Massachusetts. scott.reuben@bhs.org

Complex regional pain syndrome I (reflex sympathetic dystrophy).

Immune activation and autoimmunity in chronic pain conditions and response to immunoglobulin G.

Complex regional pain syndrome (CRPS) is a chronic pain disorder characterized by pain that is disproportionate to the inciting event. Autonomic and inflammatory responses predominate, and treatment plans that explicitly target these responses reduce symptoms for longer periods of time, are typically better tolerated, and have more favorable outcomes.Our patient was a young male who presented with a four-month history of a road traffic accident (RTA) that resulted in a fractured left distal radius and scaphoid. His main complaint was pain and discomfort, even after surgical forearm stabilization, as well as hyperesthesia, restricted range of motion, and new-onset tremors. The patient was provisionally diagnosed with complex regional pain syndrome (CRPS) and booked for a fluoroscopically guided stellate ganglion block when the oral medication regime provided minimal relief. A stellate ganglion block was administered using a combination of ropivacaine, methylprednisolone, and dexmedetomidine under fluoroscopic guidance. During our routine outpatient follow-ups, our patient's pain score on the visual analog scale (VAS) fell to zero, the burning, vasomotor, and temperature abnormalities subsided, and he gradually regained the use of his left forearm and hand.The etiology of complex regional pain syndrome is multifaceted. Early identification and therapy typically halt the progression. Long-term outcomes are improved by treatment strategies that target inflammatory and autonomic responses. Dexmedetomidine has a mild anti-nociceptive action when used as an adjuvant in peripheral nerve blocks and ganglion blocks, blocking pain transmission in Aδ and C fibers. We feel that by combining dexmedetomidine and a stellate ganglion block, we could provide immediate and long-term relief to our patient. More research is needed to monitor and analyze the efficacy of dexmedetomidine as a treatment for chronic pain syndromes such as CRPS.

Complex regional pain syndrome (CRPS) is a debilitating condition with severe chronic pain in the affected regions of the body. Stellate ganglion block is used as one of the treatment modalities for sympathetically mediated chronic pain like Complex regional pain syndrome(CRPS) and various peripheral vascular diseases. 5%dextrose injection as compared to steroid injections have various beneficial effects for stellate ganglion block. We report a case of Complex regional pain syndrome (CRPS) with various motor, sensory and autonomic changes in her right upper limb.Ultrasound guided diagnostic right stellate ganglion block with 5% dextrose was done with immediate pain relief. Patient reported significant reduction in her symptoms (&gt;80% ).Later after 1 week C-arm guided radiofrquency of T2-T3 sympathetic gangion was performed .Use of 5% dextrose injection in pain medicine could be one of the promising methods for diagnosing and treating various painful conditions. Perineural dextrose injection in stellate gangion seems to be more beneficial compared to steroid injections due to the close vicinity of the gangion to various vascular structures in the neck.

Objectives:To study reduction in pain score after treatment with intravenous regional anesthesia (IVRA) and Stellate ganglion block (SGB) combination on complex regional pain syndrome (CPRS) patients and to quantify patients’ satisfaction with treatment and occurrence of complications.Methods:This is a record-based retrospective review carried out in 2020, targeting patients treated in the University of Jordan Hospital, Amman, Jordan, over the years 2002-2020.Results:Among 99 patients, a significant drop in pain scores occurred in 88% of the patients’ sample. Gender, age, type of CRPS, and duration of symptoms didn’t affect statistical results. An average of 8.6 sessions needed to achieve 50% drop in pain score, and 2-3 sessions for first clinical improvement. Patients with previous application of plaster of Paris had increased success rates.Conclusion:We find it practical, inexpensive, safe, and straightforward to combine SGB with IVRA for CRPS patients.

Surgery on the affected upper extremity of patients with a history of complex regional pain syndrome: a retrospective study of 100 patients.