Ultrasound-guided Pararadicular Injection in the Lumbar Spine: A Comparative Study of the Paramedian Sagittal and Paramedian Sagittal Oblique Approaches.

BACKGROUND: Ultrasound-guided nerve root blocks and transforaminal injections are well established, and several procedural feasibility studies have been reported. However, the contrast dispersion pattern during ultrasound-guided pararadicular injection has not been reported. We hypothesized that the paramedian sagittal oblique approach provides a superior intraforaminal contrast-spread pattern compared to the paramedian sagittal approach during ultrasound-guided pararadicular injections in the lumbar spine. METHODS: Ninety injections were performed in 42 adult patients using pararadicular injections. Each injection was allocated to 1 of 2 groups. In the paramedian sagittal approach group, the transducer was positioned perpendicularly over the skin, and a bent needle was inserted using an in-plane technique. In the paramedian sagittal oblique approach group, the needle was advanced with the transducer tilted ~20 to 25° toward the pararadicular aditus plane. In both groups, the needle was advanced until the intertransverse ligament was punctured. Nonionic contrast media was injected under fluoroscopic guidance. RESULTS: The contrast was injected in the targeted pararadicular compartment in 83 of 90 injections (92.2%). Among the successful pararadicular injections, the intraforaminal contrast pattern was detected in 17 cases (39.5%) in the paramedian sagittal approach group and in 35 cases (87.5%) in the paramedian sagittal oblique approach group (P < 0.001). Both groups showed significant pain reduction compared to the baseline (P < 0.001); however, the visual analog scale for pain showed significantly lower pain in the paramedian sagittal oblique approach group compared to the paramedian sagittal approach group (P = 0.036). Rates of ventral epidural flow, intra- and extraepineural pattern of contrast, and intravascular injections were similar between the two approaches. CONCLUSION: The paramedian sagittal oblique approach delivered a superior intraforaminal contrast-spread pattern and significantly greater pain relief than the paramedian sagittal approach during ultrasound-guided pararadicular injections in the lumbar spine.

Pain acceptance-based coping in complex regional pain syndrome Type I: daily relations with pain intensity, activity, and mood.

This study aimed to examine the temporal patterning of pain acceptance-based coping, activity, and mood in patients with complex regional pain syndrome Type I (CRPS-I), by using a daily diary method. A total of 30 patients with CRPS-I seeking treatment in a tertiary pain management center located in Seoul, Korea participated in the study. Multilevel random effects analyses indicated that (a) engagement in pain acceptance-based coping was significantly associated with lower same-day pain and negative mood and greater same-day activity and positive mood; (b) pain acceptance-based coping predicted increases in activity on the following day; (c) greater pain intensity was significantly associated with lower same-day pain acceptance-based coping and activity and greater same-day negative mood; and (d) pain intensity did not predict pain acceptance-based coping, activity, or mood on the following day. These findings suggest that patients with CRPS-I may benefit from responding to pain with acceptance. Further study and eventual application of this process in CRPS-I may improve upon the success of current approaches to this problem.

Psychometric properties of a Korean version of the Chronic Pain Acceptance Questionnaire in chronic pain patients.

PURPOSE: Accepting pain rather than trying to control it has been the focus of recent pain management research. Pain acceptance often has been assessed using the chronic pain acceptance questionnaire (CPAQ). This study aimed to evaluate the factor structure and other psychometric properties of a Korean language version of the CPAQ (KCPAQ). METHODS: This study used two archival data sets collected over two different time periods at the same site in Korea, generating two samples (Total N = 361). RESULTS: Exploratory factor analysis using sample 1 (N = 182) provided support for the same two-factor structure as the original English CPAQ. Confirmatory factor analysis using sample 2 (N = 179) demonstrated the adequacy of the two-factor model obtained from sample 1. Samples 1 and 2 were combined for the reliability and validity analyses. The results indicated that the KCPAQ has good internal consistency and test-retest stability. The KCPAQ was significantly correlated with pain intensity, pain-related anxiety, depressive symptoms, physical adjustment, and psychosocial adjustment. CONCLUSION: The KCPAQ has reliability and construct validity support for the measurement of pain acceptance in a Korean patient sample with chronic pain.

Ginkgo biloba extract attenuates hyperalgesia in a rat model of vincristine-induced peripheral neuropathy.

BACKGROUND: Chemotherapy-induced peripheral neuropathy is a common, dose-limiting side effect of cancer chemotherapeutic drugs. Hyperalgesia is a common component of neuropathic pain. Ginkgo biloba extract (GBE) is an oriental herbal medicine that has various pharmacological actions. In this study, we evaluated the effects of oral GBE on hyperalgesia in a rat model of vincristine-induced neuropathy. METHODS: Male Sprague-Dawley rats (200-250 g) were injected intraperitoneally with vincristine or saline (0.1 mg/kg/d) using a 5-day-on, 2-day-off schedule over 12 days. All the behavioral tests for mechanical, cold, and heat hyperalgesia were conducted before the daily injection during the course of vincristine treatment. Rats that developed hyperalgesia 14 days after vincristine injection were randomly assigned into 4 groups. Distilled water and GBE (50, 100, and 150 mg/kg) were administered, respectively, to the individual groups. We examined the hyperalgesia at preadministration and at 15, 30, 60, 90, 120, 150, and 180 minutes after oral drug administration. RESULTS: Saline injection did not have any significant effect on mechanical, cold, and heat hyperalgesia. Vincristine injection produced mechanical and cold hyperalgesia. For the GBE groups, the paw withdrawal threshold to mechanical stimuli was significantly increased and withdrawal frequency to cold stimuli was significantly reduced versus the control group dose-dependently (P < 0.05). CONCLUSIONS: This study demonstrates that oral administration of GBE is associated with a dose-dependent antihyperalgesic effect on mechanical and cold stimuli in a rat model of vincristine-induced neuropathy.

Analgesic effects of dexmedetomidine in vincristine-evoked painful neuropathic rats.

Dexmedetomidine, which is a selective α2-adrenoceptor agonist, was recently introduced into clinical practice for its analgesic properties. The purpose of this study was to evaluate the effects of dexmedetomidine in a vincristine-evoked neuropathic rat models. Sprague-Dawley rats were injected intraperitoneally with vincristine or saline (0.1 mg/kg/day) using a 5-day-on, 2-day-off schedule for 2 weeks. Saline and dexmedetomidine (12.5, 25, 50, and 100 µg/kg) were injected to rats developed allodynia 14 days after vincristine injection, respectively. We evaluated allodynia at before, 15, 30, 60, 90, 120, 180, and 240 min, and 24 hr after intraperitoneal drug (normal saline or dexmedetomidine) injection. Saline treatment did not show any differences for all the allodynia. Maximal paw withdrawal thresholds to mechanical stimuli were 3.0 ± 0.4, 9.1 ± 1.9, 13.0 ± 3.6, 16.6 ± 2.4, and 24.4 ± 1.6 g at saline, 12.5, 25, 50, and 100 µg/kg dexmedetomidine injection, respectively. Minimal withdrawal frequency to cold stimuli were 73.3 ± 4.2, 57.1 ± 6.8, 34.3 ± 5.7, 20.0 ± 6.2, and 14.3 ± 9.5 g at saline, 12.5, 25, 50, and 100 µg/kg dexmedetomidine injection, respectively. Dexmedetomidine shows a dose-dependent antiallodynic effect on mechanical and cold stimuli in vincristine-evoked neuropathic rat models (P < 0.05).

Reversible posterior leukoencephalopathy syndrome after cervical transforaminal epidural steroid injection presenting as transient blindness.

Transforaminal epidural steroid injections have been introduced as a nonsurgical treatment for cervical pain syndromes; however, they have also raised safety concerns. We present a patient who developed a headache and bilateral visual disturbance after cervical transforaminal epidural steroid injections. Brain magnetic resonance imaging showed a high signal intensity in the posterior region on T2-weighted and fluid-attenuated inversion recovery images, and the findings of diffusion-weighted imaging and the apparent diffusion coefficient map suggested vasogenic edema. The symptoms and abnormal imaging findings disappeared during follow-up. The clinical and imaging characteristics and their complete reversibility corresponded to reversible posterior leukoencephalopathy syndrome.

The effects of preoperative intravenous acetaminophen in patients undergoing abdominal hysterectomy.

PURPOSE: Although intravenous acetaminophen is commonly used for the management of postoperative pain, very limited evidence supports the usefulness of preoperative administration. The aim of this study was to determine the analgesic effect of preoperative acetaminophen on opioid consumption, pain scores, and side effects in patients receiving an elective abdominal hysterectomy. METHODS: A randomized, double-blinded, placebo-controlled clinical trial was performed in 76 women undergoing abdominal hysterectomy. Patients received either acetaminophen 2 g (group A) or placebo (group C) intravenously 30 min before surgery under general anesthesia. Postoperative pain was treated with patient-controlled intravenous hydromorphone 0.2 mg bolus. Hydromorphone consumption, pain scores during rest and movement, and any adverse effects were recorded at 1, 2, 6, 12, and 24 h after the operation. RESULTS: Overall hydromorphone consumption was significantly lower in group A compared with group C at all the time points (P = 0.013). The total 24-h hydromorphone consumption was reduced by 30% in group A. There was no significant difference in pain scores. The incidence of postoperative nausea and vomiting after the operation were significantly lower in group A than in group C (P < 0.05). CONCLUSIONS: Premedication with acetaminophen reduced hydromorphone consumption and opioid-related side effect in patients undergoing abdominal hysterectomy, but did not significantly reduce pain intensity.

Assessment of Clinical Outcome of Lumbar Transforaminal Foraminoplasty in Patients with Lumbar Spinal Stenosis.

BACKGROUND: Lumbar spinal stenosis (LSS), a common spinal disorder that negatively affects quality of life, is a disabling condition accompanied by back pain, leg pain, and claudication. Lumbar foraminal stenosis (LFS) is often accompanied by lumbar central stenosis (LCS) and conservative treatment is often ineffective. A surgical approach, including a minimally invasive technique, is usually recommended for the conservative treatment of refractory conditions. To achieve effective decompression of LSS, a specially designed new instrument for lumbar transforaminal foraminoplasty (TFFP) can be considered before opting for surgical treatment. OBJECTIVE: To evaluate the clinical outcomes and safety of TFFP with a specially designed instrument. STUDY DESIGN: Retrospective design. SETTING: This research was conducted in a hospital outpatient surgical center. METHODS: The medical records of 112 patients who underwent TFFP from December 1, 2018 to January 1, 2020, were reviewed. Outcome measures were obtained using the numeric rating scale for pain (NRS pain), Oswestry Disability Index (ODI), and walking distance without pain for functional ability at preprocedure and 1, 3, and 6 months postprocedure. The clinical data and radiologic findings were analyzed to evaluate correlations between predictive factors and efficacy of TFFP. RESULTS: Among 112 patients who underwent TFFP, 110 were accessed and analyzed. The percentage of successful responders was 59.1%, 73.6%, and 74.5 % of 110 patients at one, 3, and 6 months, respectively. The NRS pain score, ODI, and duration of walking without radicular pain were improved significantly at the one-, 3-, and 6-month follow-up periods (all P < 0.001). No serious adverse events occurred during this study. LIMITATIONS: The limitations of this study include the possibility of bias due to nonrandomized patient selection. CONCLUSION: TFFP using the Foramoon® device (Mcarekorea, Seongnam-si, Gyeonggi-do, Republic of Korea) appeared to be effective for managing patients with LFS and LCS, who were refractory to conservative care.

Attenuation of neuropathy-induced allodynia following intraplantar injection of pregabalin.

PURPOSE: Pregabalin exhibits potent anticonvulsant, analgesic, and anxiolytic activity in animal models. However, few studies have evaluated pregabalin's potential peripheral effects on neuropathic pain. The aim of this study was to evaluate the peripheral analgesic effects of pregabalin in a rat model of neuropathic pain. METHODS: Male Sprague-Dawley rats were prepared by ligating the left L5 and L6 spinal nerves to produce neuropathic pain. Sixty rats with neuropathic pain were randomly assigned to six groups. Normal saline (control) and pregabalin (10, 20, 30, and 50 mg.kg(-1)) were administered to the plantar surface of the affected left hind paw. Pregabalin (50 mg.kg(-1)) was administered into the unaffected contralateral paw in order to determine its systemic effect. Responses to mechanical, cold, and heat stimulation were recorded at 15, 30, 60, 90, 120, 150, and 180 min after drug administration. Rotarod performance was measured to detect drug-induced side effects, including sedation and reduced motor coordination. RESULTS: Saline injected into the affected paw and a pregabalin dose of 50 mg.kg(-1) injected into the contralateral paw showed no differences for mechanical, cold, and heat allodynia. Administration of pregabalin to the affected left hind paw in the dose range of 10-50 mg.kg(-1) resulted in a dose-dependent increase in thresholds to mechanical, cold, and heat stimulation. CONCLUSION: Peripherally administered pregabalin attenuates mechanical, cold, and heat allodynia in a rat model of neuropathic pain.

Psychometric properties of a Korean version of the Pain Anxiety Symptoms Scale-20 in chronic pain patients.

BACKGROUND: The Pain Anxiety Symptoms Scale (PASS-20) consists of 20 items designed to assess four aspects of pain-related anxiety: cognitive anxiety, escape-avoidance behaviors, fear of pain, and physiological symptoms of anxiety. Although the PASS-20 is a well-established measure of pain-related anxiety in Western samples, different cultures may yield a different factor structure or different associations with pain-related outcome variables. PURPOSE: The purposes of this study were (1) to examine the factor structure of a Korean language version of the PASS-20 (KPASS-20); (2) to examine reliability and construct validity of the KPASS-20; and (3) to compare the findings of this study with those of the original psychometric study using a Western sample. METHOD: A total of 166 patients seeking treatment in a university pain management center located in Seoul, Korea participated. RESULTS: Results indicated that the KPASS-20 consists of three factors, "fearful thinking," "physiological response," and "avoidance," and has adequate reliability and construct validity estimates. On the mean total score of the KPASS-20, the Korean sample had a significantly higher score than the original Western sample. In addition, in correlation analyses between the total score of the KPASS-20, physical functioning, and pain severity, the Korean sample had significantly higher coefficients, whereas similar differences were not found in the analyses of psychological functioning and depression. CONCLUSION: The findings provide preliminary support for the reliability and validity of the KPASS-20.

Sacral nerve stimulation for the treatment of sacroiliac joint dysfunction: A case report.

INTRODUCTION: Sacroiliac joint (SIJ) dysfunction is a significant contributing factor in 10-30% of individuals with lower back pain. However, definitive diagnostic methods and treatments are still controversial. METHODS: We present a case of a 41-year-old woman with left buttock pain, referred pain to the left leg, and dyspareunia. Her visual analogue scale (VAS) pain score was 9/10. Although we performed intramuscular injection into piriformis muscle, intra-articular injection into SIJ, and radiofrequency denervation for the treatment of SIJ pain, her pain repeatedly improved and was reaggravated. Sacral nerve stimulation to the left first sacral foramen via the retrograde cephalocaudal approach was performed. RESULTS: Her VAS pain score decreased to 2-3/10 following sacral nerve stimulation to the left first sacral foramen via the retrograde cephalocaudal approach. Before undergoing sacral nerve stimulation, she had taken anti-depressants, anti-anxietics, analgesics, and anti-convulsants. After the procedure, she required intermittent analgesics only. CONCLUSIONS: Sacral nerve stimulation with a percutaneous retrograde cephalocaudal approach is considered to be a useful therapeutic option in the treatment of intractable SIJ dysfunction.

The effects of Ginkgo biloba extract EGb 761 on mechanical and cold allodynia in a rat model of neuropathic pain.

BACKGROUND: Neuropathic pain is chronic pain that is caused by an injury to the peripheral or central nervous system. The symptoms of neuropathic pain are continuing pain, hyperalgesia, and allodynia. Ginkgo biloba extract is an oriental herbal medicine that has various pharmacological actions. We examined the effect of Ginkgo biloba extract, EGb 761, on the mechanical and cold allodynia in a rat model of neuropathic pain. METHODS: Male Sprague-Dawley rats were prepared by tightly ligating the left L5 and L6 spinal nerves. All the rats developed mechanical and cold allodynia 7 days after surgery. Fifty neuropathic rats were assigned into five groups for the intraperitoneal administration of drugs. The study was double-blind and the order of the treatments was randomized. Normal saline and EGb 761 (50, 100, 150, and 200 mg/kg) were administered, respectively, to the individual groups. We examined mechanical and cold allodynia at preadministration and at 15, 30, 60, 90, 120, 150, and 180 min after intraperitoneal drug administration. Mechanical allodynia was quantified by measuring the paw withdrawal threshold to stimuli with von Frey filaments of 1.0, 1.4, 2.0, 4.0, 6.0, 8.0, 10.0, 12.0, 15.0, and 26.0 g. Cold allodynia was quantified by measuring the frequency of foot lift with applying 100% acetone. We measured the locomotor function of the neuropathic rats by using the rotarod test to reveal if EGb 761 has side effects, such as sedation or reduced motor coordination. RESULTS: The control group showed no differences for mechanical and cold allodynia. For the EGb 761 groups, the paw withdrawal thresholds to mechanical stimuli and withdrawal frequencies to cold stimuli were significantly reduced versus the preadministration values and versus the control group. The duration of antiallodynic effects increased in a dose-dependent fashion, and these were maintained for 120 min at the highest dose (P < 0.05). Only at the highest dose (200 mg/kg) did EGb 761 reduce the rotarod performance time. CONCLUSION: We conclude that Ginkgo biloba extract, EGb 761, attenuates mechanical and cold allodynia in a rat model of neuropathic pain, and it may be useful for the management of neuropathic pain.

Contrast Runoff Correlates with the Clinical Outcome of Cervical Epidural Neuroplasty Using a Racz Catheter.

BACKGROUND: Epidural neuroplasty using a Racz catheter has a therapeutic effect. Studies have found no correlation between foraminal stenosis and the outcome of epidural neuroplasty, which is thought to depend on contrast runoff. OBJECTIVE: To examine the correlation between the contrast spread pattern and pain reduction in cervical epidural neuroplasty using a Racz catheter. STUDY DESIGN: Retrospective study. SETTING: An interventional pain-management practice in a university hospital. METHODS: Fluoroscopic images were reviewed retrospectively. The spread of contrast from the neural foramen to a nerve root was called contrast runoff. If the contrast did not spread in this manner, then there was no contrast runoff. We defined successful epidural neuroplasty as a 50% or greater reduction from the pre-procedure numeric rating scale (NRS) score for total pain, and an at least 40% reduction in the neck pain and disability scale (NPDS) score. RESULTS: This study reviewed 169 patients. Among the patients who had a contrast runoff pattern, the epidural neuroplasty was rated as successful in 96 (74.4%), 97 (75.2%), 86 (66.7%), and 79 (61.2%) cases one, 3, 6, and 12 months after the procedure, respectively. When there was no contrast runoff, the epidural neuroplasty was successful in 12 (30%), 12 (30%), 10 (25%), and 10 (25%) cases at one, 3, 6, and 12 months after the procedure (P < 0.001). Logistic regression of the contrast spread pattern and predicting successful epidural neuroplasty gave similar results. Patients with a contrast runoff pattern had odds ratios of 6.788, 7.073, 6.000, and 4.740 at one, 3, 6, and 12 months, respectively (P < 0.001). LIMITATIONS: This study lacked a control group, and the patients were not classified by their diagnosed disease, such as spinal stenosis, herniated nucleus pulposus, and post-spinal surgery syndrome. CONCLUSIONS: Cervical epidural neuroplasty with a contrast runoff pattern had a higher success rate. Contrast runoff should be observed during neuroplasty, even in the presence of foraminal stenosis. KEY WORDS: Cervical spinal pain, contrast, contrast runoff, epidural neuroplasty, percutaneous adhesiolysis, Racz catheter.

Assessment of clinical outcomes of cervical epidural neuroplasty using a Racz-catheter and predictive factors of efficacy in patients with cervical spinal pain.

BACKGROUND: Epidural neuroplasty using the Racz catheter has a therapeutic effect in patients with cervical disc herniation and central stenosis who do not respond to fluoroscopically guided epidural injections. OBJECTIVE: To evaluate the clinical outcomes of cervical epidural neuroplasty in patients with posterior neck and upper extremity pain and to demonstrate correlations between predictive factors and unsuccessful results of cervical epidural neuroplasty. STUDY DESIGN: Observational study. SETTING: An interventional pain management practice in a university hospital. METHODS: Outcome measures were obtained using the numeric rating scale (NRS) for total pain, neck pain, arm pain, and sleep disturbance; and the neck pain and disability scale (NPDS); as well as opioid consumption at preprocedure, one month, 3, 6, and 12 months after procedure. Successful epidural neuroplasty was defined as 50% or greater reduction from the preprocedure NRS for total pain, and at least a 40% reduction in the NPDS. We obtained clinical data and radiologic findings to evaluate correlations between predictive factors and efficacy of epidural neuroplasty. RESULTS: Of the 169 patients, successful outcomes were observed in 108 patients (63.9%) at one month following the procedure, in 109 patients (64.5%) at 3 months, in 96 patients (56.8%) at 6 months, and in 89 patients (52.7%) at 12 months. Previous surgery, spondylolisthesis, and ossification of the posterior longitudinal ligament were significantly associated with unsuccessful outcomes as measured by NRS and NPDS (P < 0.05). LIMITATIONS: Limitations of this evaluation include the lack of a placebo group. CONCLUSIONS: Cervical epidural neuroplasty may be an effective treatment for pain reduction and functional improvement in patients with cervical spinal pain who did not respond to conservative treatment, and may decrease surgical demand. Previous surgery, spondylolisthesis, and ossification of the posterior longitudinal ligament are associated with unsuccessful outcomes of epidural neuroplasty.

Radiologic Analysis and Clinical Study of the Upper One-third Joint Technique for Fluoroscopically Guided Sacroiliac Joint Injection.

BACKGROUND: Sacroiliac intraarticular injection by the traditional technique can be challenging to perform when the joint is covered with osteophytes or is extremely narrow. OBJECTIVE: To examine whether there is enough space for the needle to be advanced from the L5-S1 interspinous space to the upper one-third sacroiliac joint (SIJ) by magnetic resonance image (MRI) analysis as an alternative to fluoroscopically guided SIJ injection with the lower one-third joint technique, and to determine the feasibility of this novel technique in clinical practice. STUDY DESIGN: MRI analysis and observational study. SETTING: An interventional pain management practice at a university hospital. METHODS: We analyzed 200 axial T2-weighted MRIs between the L5 and S1 vertebrae of 100 consecutive patients. The following measurements were obtained on both sides: 1) the thickness of fat in the midline; 2) the distance between the midline (Point C) and the junction (Point A) of the skin and the imaginary line that connects the SIJ and the most medial cortex of the ilium; 3) the distance between the midline (Point C) and the junction (Point B) of the skin and the imaginary line that connects the SIJ and the L5 spinous process; 4) the distance between the SIJ and midline (Point C) on the skin, or between the SIJ and the midpoint (Point C') of the line from Point A to Point B; and 5) the angle between the sagittal line and the imaginary line that connects the SIJ and the midline on the skin. The upper one-third joint technique was performed to establish the feasibility of the alternative technique in 20 patients who had unsuccessful sacroiliac intraarticular injections using the lower one-third joint technique. RESULTS: The mean distances from the midline to Point A and to Point B were 21.9 ± 13.7 mm and 27.8 ± 13.6 mm, respectively. The mean distance between the SIJ and Point C (or Point C') was 81.0 ± 13.3 mm. The angle between the sagittal line and the imaginary line that connects the SIJ and the midline on the skin was 42.8 ± 5.1°. The success rate of sacroiliac intraarticular injections with the upper one-third joint technique was 90% (18/20). LIMITATIONS: This was an observational study and lacked a control group. CONCLUSIONS: Sacroiliac intraarticular injections with the upper one-third joint technique are advisable when it is hard to perform them with the lower one-third joint technique.

Adrenergic sensitivity of the sensory receptors modulating mechanical allodynia in a rat neuropathic pain model.

This study focuses on changes in adrenergic sensitivity in untransected sensory axons that innervate an area of skin made neuropathic by transection of neighboring nerves. The segmental nerve injury model is favorable for this since all axons in the L5 and L6 nerves are transected whereas the L4 axons are intact. Earlier findings are that pain behaviors develop after this injury and that these behaviors are ameliorated by sympathectomy. The present study shows that behavior indicating mechanical allodynia can be rekindled after sympathectomy by intradermal norepinephrine and alpha-2 but not alpha-1 adrenergic ligands and the rekindling can be blocked by alpha-2 but not alpha-1 adrenergic antagonists. By contrast neither intradermal norepinephrine nor other adrenergic agonists or antagonists have any demonstrable effects in the normal or after either neuropathic surgery or sympathectomy alone. These data suggest that the combination of neuropathic surgery and sympathectomy results in an upregulation of active alpha-2 adrenergic receptors on the undamaged sensory axons that provide the remaining sensory innervation to a neuropathic area partially denervated by segmental nerve lesions. These changes on undamaged axons presumably compliment similar changes on the transected axons and, thus play a role in the development of neuropathic pain.

Motor cortex stimulation in a patient with intractable complex regional pain syndrome type II with hemibody involvement. Case report.

The authors describe the effectiveness of motor cortex stimulation (MCS) in a patient with complex regional pain syndrome (CRPS) Type II, formerly known as causalgia, with hemibody allodynia. During MCS, a subjective sensation of warm paresthesia developed in the painful hand and forearm and spread toward the trunk. Pain and allodynia in the areas associated with this sensation were alleviated significantly. The analgesic effect of stimulation proved to be long lasting and was still present at the 12-month follow up. The authors speculate that MCS might exert its effect through the modulation of thalamic activity in this particular case of CRPS with hemisensory deficit. A central mechanism associated with functional disturbance in noxious-event processing in the thalamus might have an important role in the pathogenesis of the condition.

Assessment of factors affecting the difficulty of caudal epidural injections in adults using ultrasound.

BACKGROUND: In unaided caudal epidural block (CEB), incorrect needle insertion has been reported to occur in 15% to 38% of attempts. OBJECTIVE: To statistically analyze the anatomical variables affecting difficult CEB using ultrasonographic measurement. METHODS: Preprocedural ultrasonography was performed and the following measurements were obtained in 146 patients: the distance from the skin to the apex of the sacral hiatus; the depth of the sacral canal at the apex of the sacral hiatus; the length of the sacrococcygeal ligament between the apex of the sacral hiatus and sacral base; the distance from the skin to the apex of the sacral cornu; and the distance between the apexes of bilateral cornua. One clinician, unaware of the ultrasonographic findings, performed the injections using the landmark technique. The procedures were videotaped and were subsequently reviewed by an independent investigator. RESULTS: The means (± SDs) of the abovementioned measurements were 12.1±3.7 mm, 6.1±2.1 mm, 25.9±7.4 mm, 10.0±4.0 mm and 16.4±3.2 mm, respectively. Injections failed in 16 (11%) patients and were defined as difficult in 21 (14.4%) patients. The depth of the sacral canal at the apex of sacral hiatus (P<0.001) and the length of the sacrococcygeal ligament between the apex of the sacral hiatus and sacral base (P=0.001) were significant predictors of difficult CEB. Of all patients, 85.7% and 75.2% were correctly classified as difficult or not difficult, respectively. The cutoff values of the depth of the sacral canal at the apex of the sacral hiatus and the length of the sacrococcygeal ligament between the apex of the sacral hiatus and the sacral base to predict a difficult CEB were 3.7 mm and 17.6 mm, respectively. CONCLUSIONS: Both the depth of the sacral canal at the apex of the sacral hiatus and the length of the sacrococcygeal ligament between the apex of the sacral hiatus and sacral base are significant variables affecting the difficulty of the CEB.

Ultrasound-guided Pulsed Radiofrequency of the Third Occipital Nerve.

A C2-3 zygapophygeal joint is a major source of cervicogenic headache. Radiofrequency (RF) neurotomy is preformed widely for zygapophygeal joint pain. Conventional RF denervation technique is generally performed under fluoroscopic control. Recently, ultrasound-guided radiofrequency on zygapophygeal joint has emerged as an alternative method. We report our experiences of two successful ultrasound-guided pulsed radiofrequencies on 39-year-old and 42-year-old males, who complained occipital headache and posterior neck pain.

Stevens-johnson syndrome induced by carbamazepine treatment in a patient who previously had carbamazepine induced pruritus - a case report -.

Stevens-Johnson syndrome (SJS) is a rare but life-threatening skin reaction disease and carbamazepine is one of its most common causes. We report a case of SJS secondary to carbamazepine in a patient with previous pruritus due to carbamazepine which was given for treatment of trigeminal neuralgia. We would like to caution all providers that carbamazepine readministration should be avoided in the patient with a previous history of SJS or adverse skin reaction. In addition, we strongly recommend gradual titration when initiating treatment with carbamazepine.