Percutaneous electrical nerve stimulation: an alternative to TENS in the management of sciatica.

Sciatica is a common pain problem and current pharmacologic therapies have proven inadequate for many patients. The objective of this sham-controlled investigation was to compare a novel non-pharmacologic technique, percutaneous electrical nerve stimulation (PENS), to transcutaneous electrical nerve stimulation (TENS) in the management of the radicular pain associated with sciatica. Sixty-four consenting patients with sciatica due to lumbar disc herniation were treated with PENS, TENS and sham-PENS according to a randomized, single-blinded, cross-over study. All patients had been maintained on a stable oral non-opioid analgesic regimen for at least 6 weeks prior to entering the study. Each treatment modality was administered for a period of 30 min three times per week for 3 weeks, with 1 week 'off' between each modality. Both PENS and TENS treatments were administered using a stimulation frequency of 4 Hz. The pre-treatment assessment included the health status survey short form (SF-36), as well as visual analog scales (VAS) for radicular pain, physical activity and quality of sleep. The pain VAS was also repeated after each treatment session. At the end of each 3-week treatment block, the SF-36 was repeated. After receiving all three treatment modalities, a global assessment questionnaire was completed. Both PENS (42%) and TENS (23%) were significantly more effective than the sham (8%) treatments in decreasing VAS pain scores. The daily oral analgesic requirements were also significantly reduced compared to the pre-treatment values with PENS (P<0.01) and TENS (P<0.05). However, PENS was significantly more effective than TENS (and sham-PENS) in improving physical activity and quality of sleep. The SF-36 evaluation confirmed the superiority of PENS (versus TENS and sham-PENS) with respect to post-treatment functionality. In the overall assessment, 73% of the patients reported that PENS was the most desirable modality (versus 21% for TENS and 6% for sham-PENS). Finally, 71% of the patients stated that they would be willing to pay extra to receive PENS therapy compared to 22% and 3% for TENS and sham-PENS, respectively. In this sham-controlled study, we concluded that PENS was more effective than TENS when administered at a stimulation frequency of 4 Hz in providing short-term pain relief and improved functionality in patients with sciatica.     

Use of percutaneous electrical nerve stimulation (PENS) in the short-term management of headache

OBJECTIVE: To evaluate the short-term effects of percutaneous electrical nerve stimulation (PENS) in the management of three types of chronic headache. BACKGROUND: Traditional electroanalgesic therapies have been reported to be effective in the management of acute headache symptoms. However, no controlled studies have been performed in patients with chronic headache. METHODS: Thirty patients with either tension headache, migraine, or posttraumatic headache symptoms of at least 6 months' duration were randomized to receive PENS (needles with electricity) or "needles alone" according to a crossover study design. All treatments were administered for 30 minutes, three times a week for 2 consecutive weeks with 1 week off between the two different treatments. For the PENS treatments, an alternating electrical stimulation frequency of 15 and 30 Hz was used. Pain, activity, and sleep scores were assessed using a 10-cm visual analog scale, with 0 corresponding to the best and 10 to the worst, during the 48-hour period prior to the beginning of the two treatments, immediately before and after each treatment session, and 48 hours after completing each treatment modality. RESULTS: Compared with the needles alone, PENS therapy was significantly more effective in decreasing the overall VAS pain scores for tension-type headache, migraine and posttraumatic headache (58%, 59%, and 52% versus 20%, 15%, and 20%, respectively). Similarly, PENS therapy produced greater improvement in the patients' physical activity (41% to 58% for PENS versus 11% to 21% for needles only) and quality of sleep (41% to 48% for PENS versus 12% to 20% for needles only). However, there were no differences in the pattern of the response to PENS therapy among the three headache groups. CONCLUSIONS: Percutaneous electrical nerve stimulation appears to be a useful complementary therapy to analgesic and antimigraine drugs for the short-term management of headache. Interestingly, the analgesic response to PENS therapy appears to be independent of the origin of the headache symptoms.     

Daily repetitive transcranial magnetic stimulation of primary motor cortex for neuropathic pain: A randomized,multicenter, double-blind,crossover, sham-controlled trial

There is little evidence for multisession repetitive transcranial magnetic stimulation (rTMS) on pain relief in patients with neuropathic pain (NP), although single-session rTMS was suggested to provide transient pain relief in NP patients. We aimed to assess the efficacy and safety of 10 daily rTMS in NP patients. We conducted a randomized, double-blind, sham-controlled, crossover study at 7 centers. Seventy NP patients were randomly assigned to 2 groups. A series of 10 daily 5-Hz rTMS (500 pulses/session) of primary motor cortex (M1) or sham stimulation was applied to each patient with a follow-up of 17 days. The primary outcome was short-term pain relief assessed using a visual analogue scale (VAS). The secondary outcomes were short-term change in the short form of the McGill pain questionnaire (SF-MPQ), cumulative changes in the following scores (VAS, SF-MPQ, the Patient Global Impression of Change scale [PGIC], and the Beck Depression Inventory [BDI]), and the incidence of adverse events. Analysis was by intention to treat. This trial is registered with the University hospital Medical Information Network Clinical Trials Registry. Sixty-four NP patients were included in the intention-to-treat analysis. The real rTMS, compared with the sham, showed significant short-term improvements in VAS and SF-MPQ scores without a carry-over effect. PGIC scores were significantly better in real rTMS compared with sham during the period with daily rTMS. There were no significant cumulative improvements in VAS, SF-MPQ, and BDI. No serious adverse events were observed. Our findings demonstrate that daily high-frequency rTMS of M1 is tolerable and transiently provides modest pain relief in NP patients.     

Percutaneous neuromodulation therapy; does the location of electrical stimulation effect the acute analgesic response? (University of Texas Southwestern Medical Center at Dallas,Dallas, TX) Anesth Analg 2000;91:949–954.

This article studied the effect of the location of electrical stimulation on the acute analgesic response to percutaneous neuromodulation therapy in patients with nonradiating neck pain. Sixty‐eight patients received 3 different nonpharmacologic modalities, namely “needles only (neck), local (neck) dermatomal stimulation, and remote (lower back) dermatomal stimulation in a random sequence over the course of an 11‐week study period. All treatments were given for 30 min, 3 times per week for 3 weeks with 1 week “off” between each modality. The assessment tools included the health status survey short form (SF‐36) questionnaire as well as 10‐cm visual analog scales for assessing pain, physical activity, and quality of sleep. The pain visual analog scale was repeated 5‐10 min after each treatment session. The daily oral nonopioid analgesic requirements were recorded in the patient diary during the entire study period. At the end of each 3‐week treatment block, the SF‐36 questionnaire was repeated. Compared with needles only and remote dermatomal stimulation, local dermatomal stimulation produced a significantly greater decrease in pain, increase in physical activity, and improvement in the quality of sleep compared with baseline values (P < 0.05). The posttreatment SF‐36 test results revealed that all 3 modalities produced improvements compared with the prestudy scores for both the physical component summary and mental component summary. However, the magnitude of the changes in the physical component summary and mental component summary with local dermatomal stimulation was significantly greater than needle only or remote dermatomal stimulation. No side effects were reported at the needle insertion sites. Conclude that electrical stimulation at the specific dermatomal levels corresponding to the local pathology produces greater short‐term improvements in pain control, physical activity, and quality of sleep in patients with chronic neck pain. Comment by Alan Kaye, M.D. Percutaneous neuromodulation is a therapy in which percutaneous electrical nerve stimulation is applied for short‐term relief of various pain syndromes. In this study involving 68 patients by White et al, the effects of neuromodulation therapy were studied with nonradiating neck pain. Local dermatomal stimulation consisted of placement of 10 32‐gauge stainless steel acupuncture needle probes to a depth of 2‐4 cm into the soft tissue and paraspinous muscles in the cervical region. For electrical therapy, 10 probes were connected to 5 bipolar leads from a low‐output electrical generator and stimulated for 30 min at 15 and 30 cycles/s. Finally, remote dermatomal electrical therapy consisted of placement of 10 32‐gauge stainless steel acupuncture‐like needle probes to a depth of 2‐4 cm into the soft tissue and/or paraspinous muscle in the lower back region. Each modality was administered to all patients 3 times per week for 3 consecutive weeks with 1 week off between each modality. Most parameters compared after demonstrated improvement locally and a reduction in daily usage of oral nonopioid analgesic medications. Future studies are warranted, in particular those in which long‐term benefits are assessed. The authors should be commended for studying this alternative treatment strategy and its role in mediating or modulating complex pain syndromes.     

Comparison of therapeutic duration of therapeutic ultrasound in patients with knee osteoarthritis

[Purpose] The aim of study was to compare different durations of ultrasound in patients with knee osteoarthritis. [Subjects and Methods] One hundred patients diagnosed with bilateral knee osteoarthritis (OA) were enrolled in this study. Patients were divided into two groups. The first group (G1) received 4 minutes of ultrasound. The second group (G2) received the exact same treatment, but the duration of ultrasound was longer at 8 minutes. Patients in both groups underwent a total of 10 ultrasound over 2 weeks. Following treatment, all patients provided self-evaluations of pain via the Visual Analog Scale (VAS), overall physical function with WOMAC, disability via the Lequesne index (Leq), and depressive symptoms with the Beck Depression Index (BDI). [Results] There were no significant differences in VAS, WOMAC Leq, and BDI values between groups 1 and 2. After treatment, VAS, WOMAC, Leq, and BDI values improved for both treatment groups. However, following treatment, G2 had significantly greater values for WOMAC functional and total scores than G1. No statistically significant differences were observed for VAS scores while inactive, WOMAC pain and stiffness scores, and BDI values after treatment between both groups. VAS pain scores while active and Leq index values were significantly lower in G1 than G2. [Conclusion] Patients in both groups demonstrated improved functionality, pain and psychological status following a consistent, 2-week regimen of 4-minute or 8-minute treatments with ultrasound. Yet, patients that experienced longer treatment durations of 8 minutes demonstrated better outcomes in pain and the ability to carry out activities of daily living.Key words: Knee, Ultrasound, Osteoarthritis     

普瑞巴林治疗老年带状疱疹后神经痛的疗效研究

目的:比较口服普瑞巴林与奥卡西平治疗老年带状疱疹后神经痛(PHN)的临床疗效与安全性。方法:老年PHN患者60例随机分成A、B组各30例,2组均常规给予维生素B1、甲钴胺治疗,A组加口服普瑞巴林治疗,B组则口服奥卡西平,均治疗4周。比较2组患者治疗前、治疗后1、2、4周疼痛视觉模拟评分(VAS)和睡眠评分(汉密尔顿抑郁量表的第4、5、6项)。结果:2组患者治疗后VAS和睡眠评分均低于治疗前(P<0.05),A组在治疗后1周VAS及睡眠评分明显低于B组(P<0.01);A组治疗后疼痛缓解程度优于B组;两组无明显药物不良反应。结论:口服普瑞巴林治疗老年带状疱疹后神经痛起效快、可显著改善睡眠,无严重不良反应发生。     

Elektrostimulationsakupunktur bei peripheren neuropathischen Schmerzsyndromen

AIM: The aim of this pilot study was to investigate the potential value of acupuncture in the treatment of peripheral neuropathic pain. Explorative analysis should provide data for further randomised controlled trials. METHOD: In an uncontrolled clinical trial electroacupuncture was given to 17 patients with chronic neuropathic pain of peripheral origin which was resistant to preceding pain therapy. Patients were treated twice weekly for 4 weeks. Assessment of outcome measurements comprised: Intensity of continuous pain (visual analogue scale, VAS), intensity of pain attacks (VAS), duration of pain attacks, number of pain attacks and changes in mood (VAS). All measures were evaluated by diary (1 week before treatment to 2 weeks after treatment and 1 week at follow up three months after treatment). Changes of global complaints and patients' beliefs in treatment (credibility assessment) were also assessed. RESULTS: At re-evaluation two weeks after treatment, mean continuous pain was reduced by 32.9% and intensity of pain attacks was reduced by 59%. Mean number of daily pain attacks decreased from 4.2 (SD +/- 4.6, 0.14-13.3) before treatment to 2.2 (SD +/- 3.8, 0-7.5) two weeks after treatment. Duration of pain attacks and mood showed no substantial changes. Three months after treatment, continuous pain was reduced by 15.9% and intensity of pain attacks was reduced by 44% compared to baseline. No serious adverse events were observed CONCLUSIONS: On the basis of this small pilot study, trial treatment by electroacupuncture seems to be justified in these patients given a lack of success of standard treatments. The apparent beneficial analgesic effects of electroacupuncture appear to warrant further investigation.     

Anxiety-like behaviour in rats with mononeuropathy is reduced by the analgesic drugs morphine and gabapentin

Anxiety has been described as an important comorbidity in patients suffering from chronic pain. However, in animals the connection between persistent pain and anxiety has hardly been investigated. Therefore, in the current study it was assessed whether chronic pain also causes anxiety-like behaviour in animals and if it can be reversed by analgesic or anxiolytic drugs. Neuropathic pain was induced in rats by partial sciatic nerve ligation (PNL) and chronic constriction injury (CCI). Mechanical hypersensitivity was assessed by the "electronic algometer", while anxiety-like behaviour was measured by using the elevated plus maze. In both neuropathic pain models, rats exhibited mechanical hypersensitivity, whereas a significant increase in anxiety-like behaviour was observed only in CCI rats (time spent in open arms decreased significantly from 99+/-15.8s in sham animals to 33.4+/-7.5s in CCI animals). Furthermore, midazolam (0.5mg/kg; i.p.) significantly reduced anxiety-like behaviour in both sham- and CCI-operated animals without influencing mechanical hypersensitivity. Morphine (3mg/kg; i.p.) and gabapentin (30 mg/kg; i.p.) significantly attenuated anxiety-like behaviour in the CCI lesioned rats: morphine increased entries into open arms from 3.0+/-0.4 to 7.7+/-1.4 (P=0.01), gabapentin elevated this value from 4.7+/-1 to 7.5+/-0.9 (P=0.02). These data suggest that rats subjected to neuropathic pain models develop anxiety-like behaviour which can be reversed by appropriate analgesic treatment. Morphine and gabapentin had no anxiolytic-like effect in sham treated animals, thus their effect on anxiety-like behaviour in the neuropathic pain model is likely indirect via their anti-nociceptive properties.     

High-dose tramadol in comparison to low-dose morphine for cancer pain relief.

Cancer pain treatment following the World Health Organization guidelines is effective and feasible. However, the evidence supporting the use of opioids for mild to moderate pain on the second step of the analgesic ladder is widely discussed. The present evaluation compares the efficacy and safety of high doses of oral tramadol (> or = 300 mg/d) with low doses of oral morphine (< or = 60 mg/d). Patients were included in this nonblinded and nonrandomized study if the combination of a nonopioid analgesic and up to 250 mg/d of oral tramadol was inadequate. 810 patients received oral tramadol for a total of 23,497 days, and 848 patients received oral morphine for a total of 24,695 days. The average dose of tramadol was 428 +/- 101 mg/d (range 300-600 mg/d); the average dose of morphine was 42 +/- 13 mg/d (range 10-60 mg/d). Additional nonopioid analgesics were given on more than 95% of days. Antiemetics, laxatives, neuroleptics, and steroids were prescribed significantly more frequently in the morphine group; the use of other adjuvants was similar in both groups. The mean pain intensity on a 0-100 numerical rating scale (NRS) was 27 +/- 21 (95% CI 26-29) in the tramadol and 26 +/- 20 (95% CI 24-27) in the morphine group (NS). The analgesic efficacy was good in 74% and 78%, satisfactory in 10% and 7%, and inadequate in 16% and 15% of patients receiving tramadol and morphine, respectively (NS). Constipation, neuropsychological symptoms, and pruritus were observed significantly more frequently with low-dose morphine; other symptoms had similar frequencies in both groups. These data suggest that tramadol can be used for the treatment of cancer pain, when nonopioids alone are not effective. High doses of tramadol are effective and safe.     

Effects of Anodal Transcranial Direct Current Stimulation on Chronic Neuropathic Pain in Patients With Multiple Sclerosis

Neuropathic pain in patients with MS is frequent and is associated with a great interference with daily life activities. In the present study, we investigated whether anodal transcranial direct current stimulation (tDCS) may be effective in reducing central chronic pain in MS patients. Patients received sham tDCS or real tDCS in a 5-day period of treatment in a randomized, double blind, sham-controlled study. Pain was measured using visual analog scale (VAS) for pain and the short form McGill questionnaire (SF-MPQ). Quality of life was measured using the Multiple Sclerosis Quality of Life-54 scale (MSQoL-54). Depressive symptoms and anxiety were also evaluated as confounding factors using the Beck Depression Inventory (BDI) and VAS for anxiety. Evaluations were performed at baseline, immediately after the end of treatment, and once a week during a 3-week follow-up period. Following anodal but not sham tDCS over the motor cortex, there was a significant pain improvement as assessed by VAS for pain and McGill questionnaire, and of overall quality of life. No depression or anxiety changes were observed. Our results show that anodal tDCS is able to reduce pain-scale scores in MS patients with central chronic pain and that this effect outlasts the period of stimulation, leading to long-lasting clinical effects.PerspectiveThis article presents a new, noninvasive therapeutic approach to chronic, central neuropathic pain in multiple sclerosis, poorly responsive to current conventional medications. tDCS is known to cause long-lasting changes of neuronal excitability at the site of stimulation and in the connected areas in healthy subjects. This led us to hypothesize that pain decrease may be the result of functional plastic changes in brain structures involved in the pathogenesis of chronic neuropathic pain.     

Low-intensity laser therapy for painful symptoms of diabetic sensorimotor polyneuropathy: a controlled trial

OBJECTIVE: Low-intensity laser therapy (LILT) has been advocated for treatment of chronic pain disorders. Although the mechanism of pain relief is uncertain, this therapy has been suggested for relief of painful symptoms of diabetic sensorimotor polyneuropathy (DSP). The objective of this study was to determine whether LILT relieves the pain of DSP. RESEARCH DESIGN AND METHODS: We conducted a randomized, double-masked, sham therapy-controlled clinical trial in 50 patients with painful DSP diagnosed with the Toronto Clinical Neuropathy Score. All patients received sham therapy over a 2-week baseline period and were then randomized to receive biweekly sessions of either sham or LILT for 4 weeks. The primary efficacy parameter was the difference in the weekly mean pain scores on a visual analog scale (VAS). RESULTS: The patients had similar baseline characteristics for pain intensity, HbA(1c), and duration of DSP. Both groups noted a decrease in weekly mean pain scores during sham treatment. After the 4-week intervention, the LILT group had an additional reduction in weekly mean pain scores of -1.0 +/- 0.4 compared with -0.0 +/- 0.4 for the sham group (P = 0.07). LILT had no effect on the Toronto Clinical Neuropathy Score, nerve conduction studies, sympathetic skin response, or quantitative sensory testing. CONCLUSIONS: Although an encouraging trend was observed with LILT, the study results do not provide sufficient evidence to recommend this treatment for painful symptoms of DSP.     

Morphine, nortriptyline and their combination vs. placebo in patients with chronic lumbar root pain

Although lumbar radicular pain is the most common chronic neuropathic pain syndrome, there have been few randomized studies of drug treatments. We compared the efficacy of morphine (15-90 mg), nortriptyline (25-100 mg), their combination, and a benztropine "active placebo" (0.25-1 mg) in patients with chronic sciatica. Each period consisted of 5 weeks of dose escalation, 2 weeks of maintenance at the highest tolerated doses, and 2 weeks of dose tapering. The primary outcome was the mean daily leg pain score on a 0-10 scale during the maintenance period. Secondary outcomes included a 6-point ordinal global pain relief scale, the Beck Depression Inventory (BDI), the Oswestry Back Pain Disability Index (ODI) and the SF-36. In the 28 out of 61 patients who completed the study, none of the treatments produced significant reductions in average leg pain or other leg or back pain scores. Pain reduction, relative to placebo treatment was, 14% for nortriptyline (95% CI=[-2%, 30%]), 7% for morphine (95% CI=[-8%, 22%]), and 7% for the combination treatment (95% CI=[-4%, 18%]). Mean doses were: nortriptyline alone, 84+/-24.44 (SD) mg/day; morphine alone, 62+/-29 mg/day; and combination, morphine, 49+/-27 mg/day plus nortriptyline, 55 mg+/-33.18 mg/day. Over half of the study completers reported some adverse effect with morphine, nortriptyline or their combination. Within the limitations of the modest sample size and high dropout rate, these results suggest that nortriptyline, morphine and their combination may have limited effectiveness in the treatment of chronic sciatica.     

Double-blind evaluation of short-term analgesic efficacy of orally administered dexketoprofen trometamol and ketorolac in bone cancer pain

The analgesic efficacy and safety of dexketoprofen trometamol (the active enantiomer of the racemic compound ketoprofen) (25mg q.i.d.) vs. ketorolac (10mg q.i.d.) was assessed in 115 patients with bone cancer pain included in a multicenter, randomized, double-blind, parallel group study. A level of >/=40 mm on the 100 mm visual analog scale (VAS) and >/=10 in the pain rating index were required for inclusion. At the end of treatment on day 7 (+1 day), mean values of VAS were 32+/-24 mm for dexketoprofen and 40+/-30 mm for ketorolac (P=0.12) but the pain rating index was significantly lower in patients given dexketoprofen (8.5+/-2.3 vs. 9.7+/-2.9, P=0.04). Moreover, most of the patients reached a pain intensity difference from baseline >/=20 mm (75% of patients for dexketoprofen and 65% of patients for ketorolac). Around half of patients in both treatments had a pain intensity <30 mm on VAS at the end of treatment (55% for dexketoprofen and 47% for ketorolac). In the overall assessment of efficacy, a higher percentage of both patients and physicians rated dexketoprofen as 'quite effective' or 'very effective' compared to ketorolac. The percentage of patients withdrawn from the study for any reason as well as for insufficient therapeutic effect or due to adverse events was lower in the dexketoprofen group than in the ketorolac group. Treatment-related adverse events occurred in 16% of patients given dexketoprofen and in 24% given ketorolac. Serious adverse events occurred in 3.5% of patients from both groups but only one case of gastrointestinal hemorrhage was considered related to ketorolac. We conclude that dexketoprofen trometamol 25 mg q.i.d. oral route is a good analgesic therapy in the treatment of bone cancer pain, comparable to ketorolac 10 mg q.i.d., with a good tolerability profile.     

On the importance of placebo timing in rTMS studies for pain relief

The efficacy of repetitive transcranial magnetic stimulation (rTMS) of the motor cortex for neuropathic pain relief is founded on double-blind studies versus placebo. In these studies, however, the analgesic effect of active interventions remained modest compared with the placebo effect. This observation led us to re-evaluate the intrinsic placebo action on pain relief according to the relative timing of active and sham rTMS interventions. In a randomized controlled study including 45 patients, we compared the analgesic effect of sham rTMS that either preceded or followed an active rTMS, which could be itself either successful or unsuccessful. Placebo analgesia differed significantly when the sham rTMS session followed a successful or an unsuccessful active rTMS. Placebo sessions induced significant analgesia when they followed a successful rTMS (mean pain decrease of 11%), whereas they tended to worsen pain when following an unsuccessful rTMS (pain increase of 6%). Only when the sham intervention was applied before any active rTMS were placebo scores unchanged from the baseline. These results probably reflect an unconscious conditioned learning. The timing of placebo relative to active interventions should be taken into account in rTMS studies for pain relief, and possibly in other conditions too. The fact that placebo effects could be enhanced by a previous rTMS with an analgesic effect as low as 10% suggests that a 30% pain decrease threshold in therapeutic trials may be too severe because smaller analgesic effects may have a clinical significance too.     

Chronic pelvic pain treated with gabapentin and amitriptyline: A randomized controlled pilot study

BACKGROUND: The aim of this study was to compare the efficacy and side effects of gabapentin, amitriptyline, and their combination in women with chronic pelvic pain. METHODS: In this open-label, prospective, randomized trial, 56 women with chronic pelvic pain were investigated with a two-year follow-up at the Vienna Medical University Hospital. If pain intensity assessed by a visual analog scale (VAS) was 5 or more (0, no pain; 10, maximal pain), despite analgesic therapy using the nonopioid drug metamizol together with weak opioids, patients were randomized to receive gabapentin (n = 20), amitriptyline (n = 20), or a combination of both drugs (n = 16). Doses of gabapentin and amitriptyline were increased to maximum daily doses of 3600 mg and 150 mg, respectively, until sufficient pain relief or the occurrence of side effects. VAS and side effects were evaluated before treatment and at 1, 3, 6, 12 and 24 months afterwards. RESULTS: All patients experienced significant pain relief during the observation period. However, after 6, 12 and 24 months, pain relief was significantly better in patients receiving gabapentin either alone or in combination with amitriptyline than in patients receiving monotherapy with amitriptyline (gabapentin: 0 months, 7.7 +/- 1.5; 6 months, 1.6 +/- 0.9; 12 months, 1.5 +/- 0.9; 24 months, 1.9 +/- 0.9; amitriptyline: 0 months, 7.3 +/- 1.5; 6 months, 2.2 +/- 1.6; 12 months, 2.2 +/- 1.6; 24 months; 3.4 +/- 0.9; amitriptyline-gabapentin: 0 months, 7.6 +/- 0.8; 6 months, 1.3 +/- 0.9; 12 months, 1.7 +/- 1.0; 24 months, 2.3 +/- 0.9). Side effects were lower in the gabapentin group than in the two other groups, the difference reaching statistical significance after three months (P < 0.05). CONCLUSION: Gabapentin alone or in combination with amitriptyline is better than amitriptyline alone in the treatment of female chronic pelvic pain.     

Double-blind, placebo-controlled trial of lamotrigine in combination with other medications for neuropathic pain

This randomized, double-blind, placebo-controlled study was undertaken to evaluate the efficacy and tolerability of lamotrigine added to gabapentin, a tricyclic antidepressant, or a nonopioid analgesic in patients whose neuropathic pain was inadequately controlled with these medications. Patients with neuropathic pain from diabetic peripheral neuropathy, postherpetic neuralgia, traumatic/surgical nerve injury, incomplete spinal cord injury, trigeminal neuralgia, multiple sclerosis, or HIV-associated peripheral neuropathy, who had a mean weekly pain score > or =4 on an 11-point numerical rating scale, were randomized to receive a flexible dose of lamotrigine 200, 300, or 400mg daily (n=111) or placebo (n=109) for up to 14 weeks (including eight weeks of dose escalation) in addition to their prestudy regimen of gabapentin, a tricyclic antidepressant, or a nonopioid analgesic. No statistically significant difference in the mean change in pain-intensity score from baseline to Week 14 (primary endpoint) was detected between lamotrigine and placebo (P=0.67). Differences between lamotrigine and placebo were not statistically significant for secondary efficacy assessments, including mean changes from baseline in the Short-Form McGill Pain Questionnaire, the Neuropathic Pain Scale, rescue medication use, and the percentages of patients rated as much improved or very much improved at the end of treatment on the Clinician Global Impression of Change scale and the Patient Global Impression of Change scale. Lamotrigine was generally well tolerated. Lamotrigine (up to 400 mg/day) added to gabapentin, a tricyclic antidepressant, or a nonopioid analgesic did not demonstrate efficacy as an adjunctive treatment of neuropathic pain but was generally safe and well tolerated.     

Efficacy of transdermal nitroglycerin combined with etodolac for the treatment of chronic post-thoracotomy pain: an open-label prospective clinical trial

Chronic post-thoracotomy pain (CPP) is associated with surgical intercostal nerve injury. Like other forms of neuropathic pain, there is no ideal treatment. Nitroglycerin (NTG) has been found efficacious in acute pain, but has not been tested for chronic pain with neuropathic characteristics. The present study investigated the efficacy of NTG combined with the nonsteroidal anti-inflammatory drug etodolac for the treatment of CPP. Thirty of 129 patients who underwent thoracotomy within an 18-month period had moderate to severe pain that did not respond to etodolac. NTG, 5 mg/day, was added to the treatment. A significant reduction in VAS was observed on day 14 of treatment (from 66.7 +/- 11 to 42.1 +/- 5, P< 0.05). Similar changes were noted in breakthrough pain intensity and and sleep efficiency. The only side effect was mild headache, which was self-limited to the first few days of NTG administration. We conclude that NTG added to etodolac appears to be effective for the treatment of CPP, with minimal side effects. Further randomized blinded studies are required.     

rTMS for Suppressing Neuropathic Pain: A Meta-Analysis

This pooled individual data (PID)-based meta-analysis collectively assessed the analgesic effect of repetitive transcranial magnetic stimulation (rTMS) on various neuropathic pain states based on their neuroanatomical hierarchy. Available randomized controlled trials (RCTs) were screened. PID was coded for age, gender, pain neuroanatomical origins, pain duration, and treatment parameters analyses. Coded pain neuroanatomical origins consist of peripheral nerve (PN); nerve root (NR); spinal cord (SC); trigeminal nerve or ganglion (TGN); and post-stroke supraspinal related pain (PSP). Raw data of 149 patients were extracted from 5 (1 parallel, 4 cross-over) selected (from 235 articles) RCTs. A significant (P < .001) overall analgesic effect (mean percent difference in pain visual analog scale (VAS) score reduction with 95% confidence interval) was detected with greater reduction in VAS with rTMS in comparison to sham. Including the parallel study (Khedr et al), the TGN subgroup was found to have the greatest analgesic effect (28.8%), followed by PSP (16.7%), SC (14.7%), NR (10.0%), and PN (1.5%). The results were similar when we excluded the parallel study with the greatest analgesic effect observed in TGN (33.0%), followed by SC (14.7%), PSP (10.5%), NR (10.0%), and PN (1.5%). In addition, multiple (vs single, P = .003) sessions and lower (>1 and ≤10 Hz) treatment frequency range (vs >10 Hz) appears to generate better analgesic outcome. In short, rTMS appears to be more effective in suppressing centrally than peripherally originated neuropathic pain states.PerspectiveThis is the first PID-based meta-analysis to assess the differential analgesic effect of rTMS on neuropathic pain based on the neuroanatomical origins of the pain pathophysiology and treatment parameters. The derived information serves as a useful resource in regards to treatment parameters and patient population selection for future rTMS-pain studies.     

普瑞巴林治疗神经病理性疼痛的疗效与安全性分析

目的：探讨普瑞巴林治疗神经病理性疼痛的疗效其安全性。方法将58例神经病理性疼痛患者随机分为普瑞巴林组和卡马西平组各29例,分别给予普瑞巴林和卡马西平治疗,所有入组患者均在治疗前及治疗1、2、3、4周时应用疼痛视觉模拟评分法（VAS）、睡眠干扰评分法、汉密尔顿抑郁量表（HAMD）及汉密尔顿焦虑量表（HAMA）进行疗效评定,同时观察两组不良反应情况。结果两组患者治疗后VAS评分、睡眠干扰评分、HAMD、HAMA评分较治疗前均有所降低（P＜0.05）;相同治疗时间内普瑞巴林组比卡马西平组评分降低明显（P＜0.05）;治疗过程中普瑞巴林组不良反应发生率较卡马西平组低（P＜0.05）。结论普瑞巴林治疗神经病理性疼痛疗效好,不良反应发生率低。     

The validity of the neuropathic pain scale for assessing diabetic neuropathic pain in a clinical trial

OBJECTIVES: In controlled trials of analgesics for the treatment of neuropathic pain, the primary outcome variable is most often a measure of global pain intensity. However, because neuropathic pain is associated with a variety of pain sensations, the effects of analgesic treatments on different sensations could go undetected if specific pain qualities are not assessed. This study sought to evaluate the utility of assessing the multiple components of neuropathic pain in an analgesic clinical trial. METHODS: One hundred fifty-nine subjects with diabetes-related foot pain were randomly assigned to receive an active analgesic (controlled-release oxycodone) or matching placebo for 6 weeks. A multidimensional measure of neuropathic pain, the Neuropathic Pain Scale (NPS), was administered before, during, and after study treatment. RESULTS: Relative to placebo, the opioid analgesic produced statistically significantly greater decreases in global pain intensity, pain unpleasantness, and sharp, dull, and deep pain sensations. Responder analyses indicated a higher rate of responding to the opioid condition, relative to placebo, for intense, unpleasant, deep, and surface pain. The opioid analgesic did not significantly reduce hot, cold, itchy, or sensitive pain sensations compared with placebo in either analysis. CONCLUSIONS: These findings support the utility of the NPS for characterizing the multidimensional nature of the neuropathic pain experience and for detecting changes in neuropathic pain with treatment.