Pain
-
Randomized Controlled Trial Multicenter Study
The efficacy of a glial inhibitor, minocycline, for preventing persistent pain after lumbar discectomy: a randomized, double-blind, controlled study.
Minocycline strongly inhibits microglial activation, which contributes to central sensitization, a major mechanism underlying chronic pain development. We hypothesized that the perioperative administration of minocycline might decrease persistent pain after lumbar discectomy. We randomly assigned 100 patients undergoing scheduled lumbar discectomy to placebo and minocycline groups. ⋯ The incidence and intensity of neuropathic pain and functional scores did not differ between the minocycline and placebo groups. Exploratory analysis suggested that minocycline might be effective in a subgroup of patients with predominantly deep spontaneous pain at baseline. Perioperative minocycline administration for 8 days does not improve persistent pain after lumbar discectomy.
-
Randomized Controlled Trial
Oxycodone alters temporal summation but not conditioned pain modulation: preclinical findings and possible relations to mechanisms of opioid analgesia.
Opioid analgesia is mediated primarily by modulating (inhibiting and enhancing) pain mechanisms at the spinal and supraspinal levels. Advanced psychophysical paradigms of temporal summation (TS) and conditioned pain modulation (CPM) likely represent pain mechanisms at both levels. Therefore, the study of opioid effects on TS and CPM can shed light on their analgesic mechanisms in humans. ⋯ In contrast, no significant effects of either oxycodone (F=0.871, P=.458) or placebo (F=2.086, P=.106) on the magnitude of CPM were found. These results suggest that under the current experimental conditions, oxycodone exerted spinal, rather than supraspinal, analgesic effects. Furthermore, compared with CPM, TS seems more suitable for studying the mechanisms of opioid analgesia in humans.
-
Randomized Controlled Trial Multicenter Study
Efficacy and safety of tanezumab versus naproxen in the treatment of chronic low back pain.
Tanezumab is a humanized monoclonal antibody that specifically inhibits nerve growth factor as a treatment for chronic pain. This phase IIB study investigated the efficacy and safety of tanezumab for chronic low back pain vs placebo and naproxen. Patients (N=1347) received intravenous tanezumab (5, 10, or 20mg every 8weeks), naproxen (500mg twice daily), or placebo. ⋯ The most frequently reported adverse events resulting in discontinuation of tanezumab treatment were arthralgia and paresthesia; the highest frequency was observed with tanezumab 20mg (both 1.4%). Serious adverse event incidence was similar across treatments. In conclusion, tanezumab provided significantly greater improvement in pain, function, and global scores vs placebo and naproxen in patients with chronic low back pain.
-
Randomized Controlled Trial Multicenter Study
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. ⋯ 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.
-
Randomized Controlled Trial
The extent of neurocognitive dysfunction in a multidisciplinary pain centre population. Is there a relation between reported and tested neuropsychological functioning?
Patients with chronic nonmalignant pain syndromes frequently report cognitive dysfunction, in particular with respect to concentration and attention. Such complaints have, in general, been attributed to depressive symptoms. In this study we showed that cognitive complaints in chronic pain patients are significantly associated with objective test performance in the area of inhibitory control after partialling out degree of depressive symptoms. ⋯ A larger proportion of patients with generalized and neuropathic pain performed below this cut-off, whereas patients with localized pain exhibited impaired function to a lesser degree. Chronic pain patients receiving opioids did not perform worse than patients off opioid treatment. Systematic assessment of basic neurocognitive functions in centres treating chronic pain patients is warranted.