• The Korean Journal of Pain
• /
• v.33 no.3
• /
• pp.226-233
• /
• 2020

Background: We aimed to compare interlaminar epidural steroid injections (ILESI) and bilateral transforaminal epidural steroid injections (TFESI) on pain intensity, functional status, depression, walking distance, and the neuropathic component in patients with lumbar central spinal stenosis (LCSS). Methods: The patients were divided into either the ILESI or the bilateral TFESI groups. Prime outcome measures include the numerical rating scale (NRS), Oswestry disability index (ODI), Beck depression inventory (BDI), and pain-free walking distance. The douleur neuropathique en 4 questions score was used as a secondary outcome measure. Results: A total of 72 patients were finally included. NRS, ODI, and BDI scores showed a significant decline in both groups in all follow-ups. Third-month NRS scores were significantly lower in the ILESI group (P = 0.047). The percentages of decrease in the ODI and BDI scores between the baseline and the third week and third month were significantly higher in the ILESI group (P = 0.017, P = 0.001 and P = 0.048, P = 0.030, respectively). Pain-free walking distance percentages from the baseline to the third week and third month were significantly higher in the ILESI group (P = 0.036, P < 0.001). The proportion of patients with neuropathic pain in the bilateral TFESI group significantly decreased in the third week compared to the baseline (P = 0.020). Conclusions: Both ILESI and TFESI are reliable treatment options for LCSS. ILESI might be preferred because of easier application and more effectiveness. However, TFESI might be a better option in patients with more prominent neuropathic pain.

• Journal of Korean Neurosurgical Society
• /
• v.40 no.3
• /
• pp.143-147
• /
• 2006

Objective : Brachial plexus injury can produce a intractable chronic neuropathic pain. This study was undertaken to assess the long term outcome of microsurgical dorsal root entry zonotomy[MDT]. Methods : Between October 1997 and December 2002, 21 patients received MDT because of a intractable pain resulting from brachial plexus injury. Of these, 19 patients were followed for more than 2 years. Fourteen of 19 patients were male and patient ages ranged from 22 to 69 years. Mean pain duration was 36.8 months and all patients had severe pain of $9{\sim}10$ visual analogue scale. To achieve complete destruction of abnormal dorsal horns, thermocoagulation of the posterolateral sulcus were performed and careful gluing was done to prevent postoperative adhesion and pain recurrence. Results : Of the 19 patients, 15 patients had excellent [>75% reduction in pain] and good [$51{\sim}75%$ pain relief] results in a average postoperative period of 4.1 years. One patient had a poor [less than 25% pain relief] result. Three patients were considered to have a fair result [$26{\sim}50%$ pain relief]. Postoperative complications were 2 transient ipsilateral ataxia and 1 CSF fistula that resolved without surgical revision. Conclusion : These results indicate that MDT provides excellent long-term pain relief in medically intractable chronic neuropathic pain following brachial plexus injury without significant complications.

• The Korean Journal of Pain
• /
• v.27 no.4
• /
• pp.326-333
• /
• 2014

Background: Nefopam is a centrally acting non-opioid analgesic agent. Its analgesic properties may be related to the inhibitions of monoamine reuptake and the N-methyl-D-aspartate (NMDA) receptor. The antinociceptive effect of nefopam has been shown in animal models of acute and chronic pain and in humans. However, the effect of nefopam on diabetic neuropathic pain is unclear. Therefore, we investigated the preventive effect of nefopam on diabetic neuropathic pain induced by streptozotocin (STZ) in rats. Methods: Pretreatment with nefopam (30 mg/kg) was performed intraperitoneally 30 min prior to an intraperitoneal injection of STZ (60 mg/kg). Mechanical and cold allodynia were tested before, and 1 to 4 weeks after drug administration. Thermal hyperalgesia was also investigated. In addition, the transient receptor potential ankyrin 1 (TRPA1) and TRP melastatin 8 (TRPM8) expression levels in the dorsal root ganglion (DRG) were evaluated. Results: Pretreatment with nefopam significantly inhibited STZ-induced mechanical and cold allodynia, but not thermal hyperalgesia. The STZ injection increased TRPM8, but not TRPA1, expression levels in DRG neurons. Pretreatment with nefopam decreased STZ-induced TRPM8 expression levels in the DRG. Conclusions: These results demonstrate that a nefopam pretreatment has strong antiallodynic effects on STZ-induced diabetic rats, which may be associated with TRPM8 located in the DRG.

• The Korean Journal of Pain
• /
• v.26 no.2
• /
• pp.164-168
• /
• 2013

It is easy to overlook osteochondral lesions (OCLs) of the ankle in patients with chronic lower limb pain, such as complex regional pain syndrome (CRPS) or thromboangiitis obliterans (TAO, Buerger's disease). A 57-year-old woman diagnosed with type 1 CRPS, and a 58-year-old man, diagnosed with TAO, complained of tactile and cold allodynia in their lower legs. After neurolytic lumbar sympathethic ganglion block and titration of medications for neuropathic pain, each subject could walk without the aid of crutches. However, they both complained of constant pain on the left ankle during walking. Focal tenderness was noted; subsequent imaging studies revealed OCLs of her talus and his distal tibia, respectively. Immediately after percutaneous osteoplasties, the patients could walk without ankle pain. It is important to consider the presence of a hidden OCL in chronic pain patients that develop weight-bearing pain and complain of localized tenderness on the ankle.

• The Korean Journal of Pain
• /
• v.22 no.1
• /
• pp.21-27
• /
• 2009

Background: The neuropathic pain arising from nerve injury is difficult to treat and the therapeutic effects of opioid drugs remain debatable. Agonists acting at the ${\alpha}_2$ adrenergic and opioid receptors have analgesic properties and they act synergistically when co-administered in the spinal cord. The lack of subtype-selective pharmacological agents has previously impeded the synergistic effects that are mediated by the adrenergic receptor subtypes. Methods: We created neuropathic pain model by ligating the L5 spinal nerve in Sprague-Dawley rats (n = 18). We divided the rats into three groups (n = 6 for each group), and we administered intraperitoneal morphine (1 mg/kg, 3 mg/kg, 5 mg/kg) and then we measured the mechanical allodynia with using von-Frey filaments for 8 hours. We then injected morphine (5 mg/kg) intraperitoneally, twice a day for 2 weeks. We measured the tactile and cold allodynia in the morphine group (n = 9) and the saline group (n = 9). After 2 weeks, we decapitated the rats and harvested the spinal cords at the level of lumbar enlargement. We compared the ${\alpha}_2$ subtype mRNA expression with that of control group (n = 6) by performing real time polymerase chain reaction (RTPCR). Results: Intraperitoneal morphine reduced the neuropathic pain behavior in the dose-dependent manner. Chronic morphine administration showed an antiallodynic effect on the neuropathic pain rat model. The rats did not display tolerance or hyperalgesia. The expression of the mRNAs of the ${\alpha}_{2A}$, ${\alpha}_{2B}$, ${\alpha}_{2C}$ subtypes decreased, and morphine attenuated this effect. But we could not get statistically proven results. Conclusions: Systemic administration of morphine can attenuate allodynia during both the short-term and long-term time course. Morphine has an influence on the expression of ${\alpha}_2$ receptor subtype mRNA. Yet we need more research to determine the precise effect of morphine on the ${\alpha}_2$ subtype gene expression.

• Journal of Dental Anesthesia and Pain Medicine
• /
• v.20 no.6
• /
• pp.403-408
• /
• 2020

Trigeminal neuralgia (TN) involves chronic neuropathic pain, characterized by attacks of repeating short episodes of unilateral shock-like pain, which are abrupt in onset and termination. Anticonvulsants, such as carbamazepine, are the gold standard first-line drugs for pharmacological treatment. Microvascular decompression (MVD) surgery is often the course of action if pharmacological management with anticonvulsants is unsuccessful. MVD surgery is an effective therapy in approximately 83% of cases. However, persistent neuropathic pain after MVD surgery may require reintroduction of pharmacotherapy. This case report presents two patients with persistent pain after MVD requiring reintroduction of pharmacological therapy. Although MVD is successful for patients with failed pharmacological management, it is an invasive procedure and requires hospitalization of the patient. About one-third of patients suffer from recurrent TN after MVD. Often, alternative treatment protocols, including the reintroduction of medications, may be necessary to achieve improvement. This case report presents two cases of post-MVD recurrent pain. Further research is lacking on the success rates of subsequent medication therapy after MVD has proven less effective in managing TN.

• The Korean Journal of Pain
• /
• v.29 no.4
• /
• pp.239-248
• /
• 2016

Background: The present study was undertaken to evaluate the incidence of chronic persistent post-surgical pain (CPPP) and the role of signal transduction genes in patients undergoing staging laparotomy for carcinoma ovary. Methods: The present observational study was undertaken following institutional ethical committee approval and informed consent from all the participants. A total 21 patients of ASA grade I to III with age 20-70 years, scheduled for elective staging laparotomy for carcinoma ovary were included. Patients were excluded if had other causes of pain, cognitive dysfunction or chronic neurological disorders. Statistical analysis of pool data was done using SPSS version-17. For various scales like GPE, PDQ, NPSI, the visual analogue scale (VAS), global perceived effect (GPE), the pain DETECT questionnaire (PDQ), and neuropathic pain symptoms inventory (NPSI), one factor repaeted measure ANOVA applied with simple contrast with baseline as on post-operative day 1 (considered as reference and compared with subsequent time-interval), and the P values were adjusted according to "Bonferroni adjustments". In patients with CPPP, the ${\Delta}ct$ values of mRNA expressions of genes at the end of postoperative day 90 were compared with the baseline control values by one factor repeated ANOVA. P value < 0.005 significant. Results: The present study demonstrates 38.1% (8 out of 21 patients) incidence of CPPP. The functional status and quality of life as were observed to be significantly diminished in all patients with chronic pain. An up-regulation in the mRNA expression of signal transduction and a positive correlation was noted between the mRNA expression of signal transduction genes and VAS score in all patients with CPPP at the end of postoperative day 90. Conclusions: The reported incidence of CPPP in patients with carcinoma ovary was 38.1%. An up-regulation and positive correlation between mRNA expression of signal transduction genes and VAS score depicts its potential role in the pathogenesis of CPPP.

• The Korean Journal of Pain
• /
• v.12 no.1
• /
• pp.123-127
• /
• 1999

Chronic pain is a frequent complication after spinal cord injury. Various medical and surgical approaches have been applied for management of spinal cord injury pain but none of them are definitive. The N-methyl-D-Aspartate (NMDA) receptor antagonist, ketamine has been reported to have a significant effect in the management of neuropathic pain. We used small divided doses of intravenous ketamine (30 mg divided by 6 equals 5 mg, 5 min interval) in spinal cord injury patients suffering from chronic pain, and accomplished significant pain relief without side effects.

• Journal of Korean Neurosurgical Society
• /
• v.47 no.2
• /
• pp.151-154
• /
• 2010

The efficacy of spinal cord stimulation (SCS) for treatment of various chronic painful conditions is well established. Very few reports have documented the use of SCS for treatment of chronic pain after spinal cord injury. We present a case showing a good outcome after such treatment, and suggest that high cervical stimulation may be efficacious. A 53-year-old male underwent SCS on the C1-3 level for treatment of intractable neuropathic pain below the T3 level, and in the upper extremities, arising from spinal cord injury resulting from transverse myelitis caused by schistosomiasis. High cervical SCS significantly improved the pain in the upper extremities and at the T3-T10 dermatome level. The patient continues to report excellent pain relief 9 months later. The present case suggests that high cervical stimulation may improve chronic pain in the upper extremities and the T3-T10 dermatome level arising from spinal cord injury.

• The Korean Journal of Physiology and Pharmacology
• /
• v.12 no.6
• /
• pp.299-306
• /
• 2008

Sometimes, spinal cord injury (SCI) results in various chronic neuropathic pain syndromes that occur diffusely below the level of the injury. It has been reported that behavioral signs of neuropathic pain are expressed in the animal models of contusive SCI. However, the observation period is relatively short considering the natural course of pain in human SCI patients. Therefore, this study was undertaken to examine the time course of mechanical and cold allodynia in the hindpaw after a spinal cord contusion in rats for a long period of time (30 weeks). The hindpaw withdrawal threshold to mechanical stimulation was applied to the plantar surface of the hindpaw, and the withdrawal frequency to the application of acetone was measured before and after a spinal contusion. The spinal cord contusion was produced by dropping a 10 g weight from a 6.25 and 12.5 mm height using a NYU impactor. After the injury, rats showed a decreased withdrawal threshold to von Frey stimulation, indicating the development of mechanical allodynia which persisted for 30 weeks. The withdrawal threshold between the two experimental groups was similar. The response frequencies to acetone increased after the SCI, but they were developed slowly. Cold allodynia persisted for 30 weeks in 12.5 mm group. The sham animals did not show any significant behavioral changes. These results provide behavioral evidence to indicate that the below-level pain was well developed and maintained in the contusion model for a long time, suggesting a model suitable for pain research, especially in the late stage of SCI or for long term effects of analgesic intervention.