Evaluation of thoracic sympathetic ganglion block as a predictor for response to ketamine infusion therapy and spinal cord stimulation in patients with chronic upper extremity pain.

OBJECTIVE: To investigate the predictive value of thoracic sympathetic ganglion block (TSGB) in response to ketamine infusion therapy (KIT) and spinal-cord stimulation (SCS) in patients with chronic upper-extremity pain including complex regional pain syndrome (CRPS). DESIGN: Retrospective. SETTING: Tertiary hospital single-center. SUBJECTS: Patients who underwent TSGB receiving KIT or SCS within a 3-year window. METHODS: Positive TSGB outcomes were defined as ≥ 2 0-10 Numerical Rating Scale (NRS) score reduction at 2 weeks post-procedure. Positive KIT and SCS outcomes were determined by ≥ 2 NRS score reduction at 2-4 weeks post-KIT and ≥4 NRS score reduction at 2-4 weeks post-SCS implantation, respectively. RESULTS: Among 207 patients who underwent TSGB, 38 received KIT and 34 underwent SCS implantation within 3 years post-TSGB; 33 patients receiving KIT and 32 patients receiving SCS were included. Among 33 patients who received KIT, 60.6% (n = 20) reported a ≥ 2 0-10 NRS pain-score reduction. Positive response to TSGB occurred in 70.0% (n = 14) KIT responders, significantly higher than that in 30.8% (n = 4) KIT non-responders. Multivariable analysis revealed a positive association between positive responses to TSGB and KIT (OR 7.004, 95% CI 1.26-39.02). Among 32 patients who underwent SCS implantation, 68.8% (n = 22) experienced short-term effectiveness. Positive response to TSGB was significantly higher in SCS responders (45.5%, n = 10) than in non-responders (0.0%). However, there were no associations between pain reduction post-TSGB and that post-KIT or post-SCS. CONCLUSIONS: A positive response to TSGB is a potential predictor for positive KIT and SCS outcomes among patients with chronic upper-extremity pain, including CRPS.

Thoracic sympathetic ganglion blocks: real-world outcomes in 207 chronic pain patients.

BACKGROUND: Thoracic sympathetic ganglion block (TSGB) is a procedure to manage sympathetically maintained upper extremity pain (sympathetically maintained pain). To date, only a few studies have evaluated the clinical effectiveness of TSGB in pain medicine. This study investigated (1) the relationship between technical success of TSGB and pain reduction in patients with chronic upper extremity pain and (2) relevant clinical factors for a positive TSGB outcome. METHODS: We retrospectively reviewed medical data in 232 patients who received TSGB from 2004 to 2020. Technical success and a positive outcome of TSGB were defined as a temperature increase of ≥1.5°C at 20 min and a pain reduction with ≥2 points on the 11-point Numerical Rating Scale at 2 weeks post-TSGB, respectively. Correlations were assessed using correlation coefficients (R), and multivariable regression model was used to identify factors relevant to TSGB outcomes. RESULTS: 207 patients were ultimately analyzed; among them, 115 (55.5%) patients positively responded to TSGB, and 139 (67.1%) achieved technical success after TSGB. No significant relationship existed between the pain reduction and the temperature increase after TSGB (R=0.013, p=0.855). Comorbid diabetes (OR 4.200) and adjuvant intake (OR 3.451) were positively associated, and psychiatric comorbidity (OR 0.327) and pain duration (OR 0.973) were negatively associated with TSGB outcome. CONCLUSIONS: We found no significant association between the temperature increase and pain reduction after TSGB. Further studies are warranted to identify significant factors associated with TSGB outcomes in patients with complex regional pain syndrome and neuropathic pain diseases.

Soft Pneumatic Haptic Wearable to Create the Illusion of Human Touch.

The ability to deliver sensations of human-like touch within virtual reality remains an important challenge to immersive, realistic experiences. Since conventional haptic actuators impart distinctively unnatural effects, we instead tackle this challenge through the design of a rendering mechanism using soft pneumatic actuators (SPA), embedded within a wearable jacket. The resulting system is then evaluated for its ability to mimic realistic touch gesture sensations of grab, touch, tap, and tickle as performed by human fingertips. The results of our experiments indicate that the stimuli produced by our design were reasonably effective in presenting realistic human-generated sensations.

Nonorganic (Behavioral) Signs and Their Association With Epidural Corticosteroid Injection Treatment Outcomes and Psychiatric Comorbidity in Cervical Radiculopathy: A Multicenter Study.

OBJECTIVE: To determine the association between cervical nonorganic pain signs and epidural corticosteroid injection outcomes and coexisting pain and psychiatric conditions. PATIENTS AND METHODS: Seventy-eight patients with cervical radiculopathy who received epidural corticosteroid injection were observed to determine the effects that nonorganic signs have on treatment outcome. A positive outcome was a decrease of 2 or more points in average arm pain, coupled with a score of 5 on a 7-point Patient Global Impression of Change scale 4 weeks after treatment. Nine tests in 5 categories (abnormal tenderness, regional disturbances deviating from normal anatomy, overreaction, discrepancies in examination findings with distraction, and pain during sham stimulation) were modified from previous studies and standardized. Other variables examined for their association with nonorganic signs and outcomes included disease burden, psychopathology, coexisting pain conditions, and somatization. RESULTS: Of the 78 patients, 29% (n=23) had no nonorganic signs, 21% (n=16) had signs in 1 category, 10% (n=8) had signs in 2 categories, 21% (n=16) had signs in 3 categories, 10% (n=8) had signs in 4 categories, and 9% (n=7) had signs in 5 categories. The most common nonorganic sign was superficial tenderness (44%; n=34). Mean number of positive nonorganic categories was higher in individuals with negative treatment outcomes (2.5±1.8; 95% CI, 2.0 to 3.1) compared with those with positive outcomes (1.1±1.3; 95% CI, 0.7 to 1.5; P=.0002). Negative treatment outcomes were most strongly associated with regional disturbances and overreaction. Positive associations were noted between nonorganic signs and multiple pain (P=.011) and multiple psychiatric (P=.028) conditions. CONCLUSION: Cervical nonorganic signs correlate with treatment outcome, pain, and psychiatric comorbidities. Screening for these signs and psychiatric symptoms may improve treatment outcomes. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT04320836.

Sympathetic Blocks as a Predictor for Response to Ketamine Infusion in Patients with Complex Regional Pain Syndrome: A Multicenter Study.

BACKGROUND: Ketamine infusions are frequently employed for refractory complex regional pain syndrome (CRPS), but there are limited data on factors associated with treatment response. Sympathetic blocks are also commonly employed in CRPS for diagnostic and therapeutic purposes and generally precede ketamine infusions. OBJECTIVES: We sought to determine whether demographic and clinical factors, and technical and psychophysical characteristics of sympathetic blocks are associated with response to ketamine infusion. METHODS: In this multi-center retrospective study, 71 patients who underwent sympathetic blocks followed by ketamine infusions at 4 hospitals were evaluated. Sympathetically maintained pain (SMP) was defined as ≥ 50% immediate pain relief after sympathetic block and a positive response to ketamine was defined as ≥ 30% pain relief lasting over 3 weeks. RESULTS: Factors associated with a positive response to ketamine in univariable analysis were the presence of SMP (61.0% success rate vs 26.7% in those with sympathetically independent pain; P = .009) and post-block temperature increase (5.66 ± 4.20 in ketamine responders vs 3.68 ± 3.85 in non-responders; P = .043). No psychiatric factor was associated with ketamine response. In multivariable analysis, SMP (OR 6.54 [95% CI 1.83, 23.44]) and obesity (OR 8.75 [95% 1.45, 52.73]) were associated with a positive ketamine infusion outcome. CONCLUSIONS: The response to sympathetic blocks may predict response to ketamine infusion in CRPS patients, with alleviation of the affective component of pain and predilection to a positive placebo effect being possible explanations.

Myth and Truth in Opioid Consumption with Intrathecal Morphine Pump Implantation in Chronic Pain: A Retrospective Cohort Study with Claims Database in South Korea.

OBJECTIVE: To investigate the opioid consumption and the healthcare resource utilization in patients with the intrathecal drug delivery system (IDDS) therapy and the comprehensive medical management (CMM) alone. DESIGN: A retrospective cohort study with a customized claims database. SETTING: In a university-based hospital. SUBJECTS: Patients with complex regional pain syndrome, post-laminectomy syndrome, and fibromyalgia. METHODS: Using propensity score matching (1:3), we selected patients with morphine infusion through IDDS (IDDS group) and CMM alone (CMM group). The primary endpoints were comparisons of average morphine equivalents daily dosages (MEDD, mg/day) for 6 and 12 months from an index date. The number of emergency room (ER) visits and hospitalizations and the total medical expenditures were compared as secondary outcomes. RESULTS: In total, 82 patients (N = 23 in the IDDS group and N = 59 in the CMM group) were analyzed. Although a 6-month average MEDD did not reach statistical significance, a 12-month average MEDD was significantly decreased in the IDDS group compared to the CMM group (53.2 ± 46.3 vs 123.9 ± 176.4, respectively; P = 0.008). ER visits were more frequent in the IDDS group than the CMM group at baseline (5.4 vs 0.5, respectively; P = .002), which was maintained for 12 months (P < 0.001). Otherwise, the number of hospitalization and the medical expenditures for pain management were not different between the groups for 12 months. CONCLUSIONS: The combined IDDS therapy had some benefits in reducing opioid consumption for 1-year follow-up compared to the CMM alone in chronic noncancer pain patients.

Can the Rhomboid Major Muscle Be Used to Identify the Thoracic Spinal Segment on Ultrasonography? A Prospective Observational Study.

OBJECTIVE: We investigated the thoracic segment corresponding to the inferior margin of the rhomboid major muscle (RMM) using ultrasound (US) to evaluate its potential as a reliable anatomic landmark for segment identification. DESIGN: A prospective observational study. SETTING: An operating room. SUBJECTS: Patients who underwent procedures around the thoracic spine. METHODS: Four hundred segments corresponding to the RMM's inferior margin were identified through the use of paravertebral sagittal US and confirmed by fluoroscopy in 100 participants in the prone position with upward and downward shoulder rotation, comprising four datasets (up-right, up-left, down-right, and down-left). The US identification of the RMM's inferior margin was dichotomously scored (clear vs ambiguous). Each dataset was divided into two groups (dominant segment group vs remaining segments group), which were compared. Factors relevant to the dominant segment associated with the RMM's inferior border were determined through univariable analyses. RESULTS: The T6 segment was observed most commonly (59.5%) along the RMM's inferior border on paravertebral sagittal US acquired in the prone position, followed by T5 (25.0%), T7 (12.8%), and T4 (2.7%). The segments corresponding to the RMM remained unchanged by shoulder posture in most participants (n = 74, 74%). The RMM's inferior border was clearly distinguishable in 330 cases (82.5%). When the RMM's inferior border was clearly identified, the corresponding segment was likely to match T6 in all datasets, with odds ratios ranging from 3.24 to 6.2. CONCLUSIONS: The RMM's inferior border over the transverse process corresponded to T6 most frequently on paravertebral sagittal US, and its deep fascia was clearly visible in most cases.

Perceived Intensity Model of Dual-Frequency Superimposed Vibration: Pythagorean Sum.

This paper presents a model for estimating the perceived intensity of a superimposed dual-frequency vibration from the perceived intensities of its two component vibrations. Based on the previous findings in the literature, we hypothesize that the three variables follow the Pythagorean relationship. Two psychophysical experiments were performed for verification with a wide range of single-frequency and superimposed vibrations applied to the fingertip. In Experiment I, we measured the perceived intensities of a large number of single-frequency vibrations and found a psychophysical magnitude function. Experiment II was designed based on the results of Experiment I in order to test the research hypothesis. For the 108 dual-frequency vibrations tested, the Pythagorean model showed 4.0% of average error in estimating the perceived intensity of a dual-frequency vibration from those of its two components. This model is robust and practical, and can be useful for any tactile interaction applications that make use of superimposed vibrations.

Botulinum Toxin Type A for Lumbar Sympathetic Ganglion Block in Complex Regional Pain Syndrome: A Randomized Trial.

BACKGROUND: The present study was designed to test the hypothesis that botulinum toxin would prolong the duration of a lumbar sympathetic block measured through a sustained increase in skin temperature. The authors performed a randomized, double-blind, controlled trial to investigate the clinical outcome of botulinum toxin type A for lumbar sympathetic ganglion block in patients with complex regional pain syndrome. METHODS: Lumbar sympathetic ganglion block was conducted in patients with lower-extremity complex regional pain syndrome using 75 IU of botulinum toxin type A (botulinum toxin group) and local anesthetic (control group). The primary outcome was the change in the relative temperature difference on the blocked sole compared with the contralateral sole at 1 postoperative month. The secondary outcomes were the 3-month changes in relative temperature differences, as well as the pain intensity changes. RESULTS: A total of 48 participants (N = 24/group) were randomly assigned. The change in relative temperature increase was higher in the botulinum toxin group than in the control group (1.0°C ± 1.3 vs. 0.1°C ± 0.8, respectively; difference: 0.9°C [95% CI, 0.3 to 1.5]; P = 0.006), which was maintained at 3 months (1.1°C ± 0.8 vs. -0.2°C ± 1.2, respectively; P = 0.009). Moreover, pain intensity was greatly reduced in the botulinum toxin group compared with the control group at 1 month (-2.2 ± 1.0 vs. -1.0 ± 1.6, respectively; P = 0.003) and 3 months (-2.0 ± 1.0 vs. -0.6 ± 1.6, respectively; P = 0.003). There were no severe adverse events pertinent to botulinum toxin injection. CONCLUSIONS: In patients with complex regional pain syndrome, lumbar sympathetic ganglion block using botulinum toxin type A increased the temperature of the affected foot for 3 months and also reduced the pain.

Ultrasound-Guided Thoracic Paravertebral Block as a Sympathetic Blockade for Upper Extremity Neuropathic Pain: A Prospective Pilot Study.

PURPOSE: Ultrasound-guided thoracic paravertebral block (US-TPVB) is considered a treatment option for the management of acute pain in various pain-related conditions. We conducted a prospective pilot study to evaluate the possibility of US-TPVB as a sympathetic blockade in patients with neuropathic pain disorders in the upper extremities. PATIENTS AND METHODS: A total of 12 patients underwent US-TPVB between the T2 and T3 paravertebral space with 10 mL of 1% mepivacaine. The temperature change (°C) before and after the procedure was compared between the ipsilateral and contralateral hands. We counted the proportion of patients showing a temperature increase ≥1.5°C and compared a change in the pain intensity before and after the procedure. RESULTS: The median increase in the temperature change between the ipsilateral and contralateral hands was 1.54°C (interquartile range, 1.28-2.20). There were seven patients (58.3%) who showed a temperature difference ≥1.5°C between both hands after the US-TPVB. Eleven patients (91.7%) reported a reduction in pain according to the score on the 11-point numerical rating scale. No serious complications relevant to the procedure were reported. CONCLUSION: US-TPVB could be a useful technique for sympathetic blockade in patients with upper extremity pain.

Evaluation of an effectiveness and safety of the electroacupuncture in the management of intractable neuropathic pain: A prospective, open-labeled, randomized, cross-over clinical trial.

BACKGROUND: There is no sufficient evidence on the effectiveness of acupuncture for neuropathic pain. This protocol describes a study that aims to evaluate the effectiveness and safety of electroacupuncture combined with conventional medicine for patients with intractable neuropathic pain, when compared with conventional medicine alone. METHODS/DESIGN: This study is a prospective, open-labeled, randomized, cross-over clinical trial. A total of 40 patients with neuropathic pain who had a numeric rating scale (NRS) score of over 4 despite receiving conventional treatment for more than 3 months will be enrolled. Participants will receive conventional treatment for neuropathic pain (treatment C) or treatment C combined with 12 additional sessions of electroacupuncture treatment (treatment A) for 6 weeks. Participants will be randomly assigned to 1 of the 2 sequence groups (AC and CA group) with a 1:1 allocation. The differences of responder in the composite efficacy outcomes, which consist of the NRS, Brief Pain Inventory-Short Form (BPI-SF) pain subscale, and global assessment at 6 weeks after randomization will be examined as the primary outcome. Secondary outcomes include differences in the NRS, the Short-Form McGill Pain Questionnaire, BPI-SF, Fatigue Severity Scale, Hospital Anxiety and Depression Scale, Medical Outcomes Study Sleep Scale, global assessment, EQ-5D, and incremental cost-effective ratio at 6 and 15 weeks after randomization. Adverse events, vital signs, and physical examinations will be recorded to evaluate safety. DISCUSSION: The study protocol for this trial will provide up-to-date evidence on the effectiveness and safety of electroacupuncture for patients with intractable neuropathic pain. The results will be disseminated through a peer-reviewed journal and conference presentations. TRIAL REGISTRATION: Clinical Research Information Service, ID: KCT0003615. Registered on March 12, 2019. https://cris.nih.go.kr/cris/search/search_result_st01_kren.jsp?seq=13410& ltype=&rtype=.

Electroacupuncture May Improve Burning and Electric Shock-Like Neuropathic Pain: A Prospective Exploratory Pilot Study.

Objective: To test the effectiveness of electroacupuncture (EA) for managing intractable neuropathic pain (NeP) and assess the protocol for a larger confirmatory trial. Design: A prospective, multicenter, single-armed, add-on, pilot study. Settings/location: At two tertiary university-based hospitals in Seoul, Republic of Korea. Subjects: Patients with chronic peripheral NeP, who have received conventional oral medications but complained of moderate to severe pain. Interventions: Two Korean medicine doctors conducted 12 sessions of EA (2 sessions per week for 4 weeks, followed by 1 session per week for the second month) in addition to conventional treatment. Outcome measures: During the 8-week treatment period, pain intensity, pain natures such as burning, electric shock-like, temperature or mechanical hyperalgesia, and numbness, Short Form of the McGill Pain Questionnaire (SF-MPQ) and the Brief Pain Inventory (BPI-SF), the EuroQol five dimensions questionnaire, patients' satisfaction, and adverse events were evaluated. The primary endpoint was a change in pain intensity (%) at 4 weeks from the baseline. Results: Among 22 patients, 19 finished the protocol. The eight EA sessions over a month reduced pain intensity from 6.0 ± 1.6 at baseline to 3.2 ± 0.9 at 4 weeks, which was a 46.7% reduction (p < 0.001). The incidences of severe burning, electric shock-like pain, and mechanical hyperalgesia reduced at 8 weeks [36%-16% (p = 0.04), 53%-21% (p = 0.009), and 53%-26% (p = 0.03), respectively]. The affective dimensions in the SF-MPQ (p = 0.007) and the pain interference parameters, including mood (p = 0.02), relations with other people (p = 0.03), and enjoyment of life (p = 0.002) in the BPI-SF, were improved at 4 and 8 weeks. The majority of patients (68%) responded that their pain was "much or somewhat improved." Overall, 84.2% expressed "satisfaction" with their multidisciplinary management. Conclusions: EA might decrease the intensity of NeP, in particular, such as burning, electric shock-like pain, and mechanical hyperalgesia, which was accompanied by psychosocial and functional improvement. A larger study is warranted to prove the effectiveness of EA for managing refractory NeP. Trial registration: ClinicalTrials.gov: NCT03315598. Retrospectively registered on October 20, 2017.

The Long-term Effectiveness of the Automatic Position-Adaptive System in Spinal Cord Stimulation: A Retrospective Comparative Study with a Two-Year Follow-up.

OBJECTIVE: To compare the nonadaptive manual system with the position-adaptive system in subjects with permanent spinal cord stimulator (SCS) implantation over a two-year follow-up period. DESIGN: Retrospective study. SETTING: Tertiary university-based national hospital. SUBJECTS: Patients who underwent permanent SCS implantation procedures. METHODS: Patients were divided into an adaptive group and a nonadaptive group according to the type of implanted SCS device. The primary outcome was the change (%) in pain intensity from baseline between the adaptive and nonadaptive groups at 24 months after SCS implantation. The secondary outcomes were comparisons of detailed clinical variables such as the scores of patient pain and satisfaction during the two-year follow-up after SCS therapy. Further, the number of subjects with SCS removal or revision within two years after SCS implantation was investigated. RESULTS: Of 187 patients with permanent SCS implantation, 85 in the nonadaptive group and 64 in the position-adaptive group were finally analyzed. The reduction in pain intensity at 24 months was higher in the adaptive group (-38.6%) than in the nonadaptive group (-30.8%, P = 0.05). Similarly, patient satisfaction with the SCS treatment at 24 months was superior in the adaptive group than in the nonadaptive group (85.7% vs 67.5% were satisfied in each group, respectively, P = 0.024). During the two years, 5.3% of patients (N = 10) underwent SCS removal and 7.0% (N = 13) underwent revision procedures. CONCLUSIONS: There was a trend of a sustained reduction in pain intensity as well as improvement in patient satisfaction at two-year follow-up in the position-adaptive system, suggesting long-term benefit over the nonadaptive manual system during SCS treatment.

Current status of pain medicine training in anesthesiology and pain medicine residency programs in university hospitals of Korea: a survey of residents' opinions.

BACKGROUND: In Korea, anesthesiologists are expected to be mainstream pain medicine (PM) practitioners. However, anesthesiology and pain medicine (APM) residency programs mostly emphasize anesthesia learning, leading to insufficient PM learning. Therefore, this study evaluated the current status of PM training in APM residency programs in 10 Korean university hospitals. METHODS: Overall, 156 residents undergoing APM training participated anonymously in our survey, focusing on PM training. We assessed the aim, satisfaction status, duration, opinion on duration, desired duration, weaknesses of the training programs and plans of residents after graduating. We divided the residents into junior (first and second year) and senior (third and fourth year). Survey data were compared between groups. RESULTS: Senior showed significantly different level of satisfaction grade than did junior (p=0.026). Fifty-seven (81.4%) residents in junior and forty (46.5%) residents in senior underwent PM training for ≤2 months. Most (108; 69.2%) residents felt that the training period was too short for PM learning and 95 (60.9%) residents desired a training period of ≥6 months. The most commonly expressed weakness of the training was low interventional opportunity (29.7%), followed by short duration (26.6%). After residency, 80 (49.1%) residents planned to pursue a fellowship. CONCLUSIONS: Dissatisfaction with PM training was probably due to a structural tendency of the current program towards anesthesia training and insufficient clinical experience, which needs to be rectified, with a change in PM curriculum.

Complex regional pain syndrome in the young male population: a retrospective study of 200 Korean young male patients.

BACKGROUND: The aim of this study was to investigate the clinical characteristics of complex regional pain syndrome (CRPS) in young male patients in South Korea, especially focusing on the association with military service. METHODS: From January 2007 to May 2017, we investigated the electronic medical records of 430 consecutive patients, aged 18 to 30 years, who visited Seoul National University Hospital Pain Center, with a suspected diagnosis of CRPS at the initial visit. The following patient details were available for analysis: demographic and disease-related variables, relevance to military service, medications, and the treatment modalities received. RESULTS: Out of 430 patients, 245 (57.0%) were diagnosed with CRPS, of which, 200 were male patients and 45 were female patients. Of the male patients, 95 (47.5%) developed CRPS during military service. CRPS during military service was more likely to result from sprain/strain, and the incidence of CRPS was significantly higher in the lower extremities in patients from the military service group than in those from the non-military service group. During the follow-up period, 37.9% of male CRPS patients (n = 61/161) were treated successfully. Patients with moderate to severe initial pain intensity, and diagnosed during their military service, showed better outcomes. CONCLUSIONS: Our results demonstrated that manifestation of CRPS in the young Korean population was more common in male and among those male CRPS patients, about half the cases developed during the military service period.

A Randomized Comparison between 4, 6 and 8 mL of Local Anesthetic for Ultrasound-Guided Stellate Ganglion Block.

BACKGROUND: Because it affords greater accuracy than landmark-based techniques, ultrasound guidance may reduce the volume of local anesthetic required for sympathetic blockade of the upper extremity. We hypothesized that 4 mL would provide a similar clinical effect when compared to larger volumes. METHODS: One hundred and two patients with chronic neuropathic pain of the upper extremity or face were randomly assigned to receive an ultrasound-guided (USG) stellate ganglion block (SGB) with either 4 mL (group A), 6 mL (group B) or 8 mL (group C) mL of 1.0% lidocaine. Skin temperatures of the face, hand, and axillary fold were measured bilaterally at baseline, 10, 20, and 30 min after the block. Our primary outcome was the relative increase in hand temperature on the blocked side at 30 min and our non-inferiority margin was -0.6 °C. Secondary outcomes included success rate (as defined by a relative temperature increase of ≥1.5 °C), pain relief, degree of ptosis and side-effects. RESULTS: The 95% confidence intervals for the difference of the means exceeded our non-inferiority margin (A versus B: -0.76 to 0.24; A versus C: -0.89 to 0.11) for temperature changes in the hand; however, success rates were similar (44, 45 and 55% for A, B and C respectively, p = 0.651). No intergroup differences were found in temperature-related outcomes for the other measurement sites (face, axilla). The incidence of minor side-effects was significantly higher in group C and no block-related complications were noted. CONCLUSIONS: We were unable to establish the non-inferiority of a 4 mL volume for sympathetic blockade of the hand. The clinical significance of these findings is unclear as success rates were similar between the different groups. In contrast, the 6- and 8 mL volumes were not associated with greater temperature changes in the face and axilla.

Clinical outcome of percutaneous lumbar foraminoplasty using a safety-improved device in patients with lumbar foraminal spinal stenosis.

Lumbar foraminal spinal stenosis (LFSS) is defined as the narrowing of the nerve root exit associated with a herniated intervertebral disc, osteoarthritic changes in the facet joints, or a hypertrophied ligamentum flavum, which can provoke neurogenic claudication. To achieve effective and safe decompression of the lumbar spinal foramen, a specially designed instrument (Claudicare, SEAWON Meditech, Bucheon-si, Gyeonggi-do, Republic of Korea) for percutaneous lumbar foraminoplasty (PLF) was invented. The purpose of this study was to evaluate the clinical efficacy and safety of the newly devised instrument in patients with LFSS.PLF was performed for LFSS by a single pain physician. For each patient, an 11-point numerical rating scale (NRS) pain score-the Oswestry Disability Index (ODI)-and the duration of walking without radicular pain were evaluated at the 3-month follow-up. The successful responder percentage was defined as ≥50% reduction from the baseline NRS score with improvement in ODI and duration of walking.Among 24 patients who underwent PLF, 15 patients showed successful responses. The NRS pain score and duration of walking without radicular pain were improved significantly from baseline at the 3-month follow-up (P < .01). The ODI was also decreased, but the difference was not statistically significant (P = .09). The NRS pain score and walking duration without pain at 3 months were statistically significantly different between the groups (P < .001 and P = .01, respectively), whereas there was no statistically significant difference in improvement in ODI between the groups (P = .23). No serious adverse events occurred in the study.In conclusion, PLF using the Claudicare device may be an optimal and safe option for managing intractable LFSS on an outpatient basis.

Predictive Factors of Successful Percutaneous Cervical Nucleoplasty for the Treatment of Pain with Cervical Herniated Disk.

BACKGROUND: Percutaneous cervical nucleoplasty (PCN) is an effective treatment for cervical herniated intervertebral disc (C-HIVD). In this retrospective study, we evaluated clinical predictors that affect the successful outcome of PCN. METHODS: Fluoroscopically guided PCN was conducted for C-HIVD by one pain physician. Successful outcome was defined as a combination of greater than 50% pain relief on the numerical rating scale pain score, no increase in analgesics, and no cervical epidural steroid injection during the 3-month follow-up period. The relationship between outcomes and independent variables, including patient demographics, comorbid diseases, pain duration, type of disc herniation, presence of spinal stenosis, pain location, analgesics, and shape of the PCN needle tip, were investigated using multivariable analyses. RESULTS: Of 201 patients, 134 experienced a successful outcome after PCN. In the positive outcome group, shorter pain durations, rarer central canal stenosis, increased unilateral radiculopathy versus axial pain, and more frequent use of the curved tip technique, were reported. Multivariable analyses revealed that unilateral radiculopathy (P = 0.013) and use of the curved-tip technique (P = 0.027) were independent positive predictors of successful PCN outcomes; conversely, longer pain duration (P = 0.014) and concurrent spinal stenosis (P < 0.001) were negative predictors. No serious complications related to PCN occurred. CONCLUSIONS: In this study, the success rate of PCN was 66.7% in patients with C-HIVD. Shorter pain duration, the absence of cervical central canal stenosis, pain location (i.e., unilateral radiculopathy vs. axial pain), and the use of the curved-tip technique were positive predictors of successful PCN.

Does Temperature Increase by Sympathetic Neurolysis Improve Pain in Complex Regional Pain Syndrome? A Retrospective Cohort Study.

BACKGROUND: Lumbar sympathetic neurolysis (LSN) is a treatment option for complex regional pain syndrome (CRPS). We examined whether LSN-related temperature changes are associated with clinical outcome and investigated relationships between the outcome of LSN and clinical variables in patients with CRPS-I. METHODS: We included 95 patients with CRPS-I affecting a single lower extremity, by the Budapest criteria, and who underwent LSN after successful lumbar sympathetic blocks, in this retrospective study. Fluoroscopy-guided LSN was conducted with 1.5 mL of 99% alcohol at L2 and L3 vertebral levels. Positive outcome was defined as a reduction of ≥50% on a numeric rating scale pain score at 6 months after LSN. The relationship between successful outcome and clinical variables was analyzed. RESULTS: Positive LSN outcome occurred in 49.5% of patients, and it was suggested that Sympathetically maintained pain may accompany CRPS-I in 28% of patients. The overall temperature in the affected limb was increased after LSN, without contralateral limb temperature changes, but did not differ significantly between the positive and negative outcome groups (P = 0.590). Temperature after LSN in warm-type CRPS was reduced in the affected limb, without contralateral limb temperature changes. The absolute temperature change was significantly greater in cold-type than in warm-type CRPS (P = 0.026). In multivariate analysis, a short duration of pain and concurrent cold intolerance were significant factors predicting a positive outcome after LSN. CONCLUSIONS: LSN may be effective in some patients with CRPS, irrespective of temperature changes and temperature asymmetry pattern. A short duration of pain and concurrent cold intolerance significantly predict successful LSN.

Opioid sparing effect and safety of nefopam in patient controlled analgesia after laparotomy: A randomized, double blind study.

OBJECTIVES: A double-blind randomised study to evaluate the opioid sparing effect and safety of nefopam when administered via intravenous patient controlled analgesia (PCA) with fentanyl. METHODS: Patients planned for elective open laparotomy, were randomly assigned to receive into fentanyl 25 µg/ml (SF group) or nefopam 2.4 mg/ml plus fentanyl 25 µg/ml (NF group). Patients were assessed before surgery and for 24 h postoperatively. RESULTS: Total PCA fentanyl consumption was significantly lower in the NF group (n = 35) than the SF group (n = 36). Pain scores were significantly lower and patients' satisfaction with treatment significantly better in the NF group than the SF group. Dry mouth and dizziness were significantly more frequent in the NF group than the SF group. There were no other statistically significant between-group differences in the incidence of adverse events. CONCLUSIONS: Intravenous PCA using nefopam + fentanyl following laparotomy has an opioid sparing effect and is associated with a low incidence of some of the typical opioid related adverse events. TRIAL REGISTRY: Clinicaltrials.gov Registration No: NCT02596269.