Few studies have directly compared the clinical features of neuropathic and non-neuropathic pains. For this purpose, the French Neuropathic Pain Group developed a clinician-administered questionnaire named DN4 consisting of both sensory descriptors and signs related to bedside sensory examination. This questionnaire was used in a prospective study of 160 patients presenting with pain associated with a definite neurological or somatic lesion. The most common aetiologies of nervous lesions (n=89) were traumatic nerve injury, post herpetic neuralgia and post stroke pain. Non-neurological lesions (n=71) were represented by osteoarthritis, inflammatory arthropathies and mechanical low back pain. Each patient was seen independently by two experts in order to confirm the diagnosis of neuropathic or non-neuropathic pain. The prevalence of pain descriptors and sensory dysfunctions were systematically compared in the two groups of patients. The analysis of the psychometric properties of the DN4 questionnaire included: face validity, inter-rater reliability, factor analysis and logistic regression to identify the discriminant properties of items or combinations of items for the diagnosis of neuropathic pain. We found that a relatively small number of items are sufficient to discriminate neuropathic pain. The 10-item questionnaire developed in the present study constitutes a new diagnostic instrument, which might be helpful both in clinical research and daily practice.

That sumatriptan tablets are effective and well tolerated in the acute treatment of migraine has been established, but the relationship between dose and efficacy has not been adequately defined to date in clinical trials. This multinational double-blind trial (N = 1003) in which patients treated up to three migraine attacks with sumatriptan 25 mg, 50 mg, 100 mg, or placebo, with a second independently randomized dose for headache recurrence, evaluated the efficacy and tolerability of three doses of sumatriptan. The results demonstrate that all doses of sumatriptan were superior (P < 0.05) to placebo in reducing moderate or severe predose headache to mild or no headache 4 hours postdose for each of the three treated attacks; sumatriptan 50 mg and 100 mg were each superior (P < 0.05) to sumatriptan 25 mg 4 hours postdose for two of three attacks. Sumatriptan (all doses) was similarly effective at relieving nausea and photophobia or phonophobia or both and at reducing clinical disability. Headache recurrence was experienced by similar proportions of patients across treatment groups (35% to 48% after placebo; 26% to 39% after sumatriptan). Relief of recurrent headache 2 hours after the second dose of study medication occurred in greater percentages of patients using any dose of sumatriptan compared with patients using placebo to treat recurrence. The incidence of adverse events with 25-mg and 50-mg sumatriptan tablets was similar to the incidence with placebo and lower than the incidence with 100-mg sumatriptan tablets. These data provide the first demonstration from a large well-controlled clinical trial that both the 50- and 100-mg doses are more effective than the 25-mg dose and that the 50-mg dose is associated with a lower incidence of adverse events than the 100-mg dose.

We used functional magnetic resonance imaging (fMRI) to analyze changes in brain activity associated with stimulation of the cutaneous trigger zone in patients with classic trigeminal neuralgia (CTN). Fifteen consecutive patients with CTN in the second or third division of the nerve, were included in this study. The fMRI paradigm consisted of light tactile stimuli of the trigger zone and the homologous contralateral area. Stimulation of the affected side induced pain in seven patients, but was not painful in eight patients on the day of the experiment. Painful stimuli were associated with significantly increased activity in the spinal trigeminal nucleus (SpV), thalamus, primary and secondary somatosensory cortices (S1, S2), anterior cingulate cortex (ACC), insula, premotor/motor cortex, prefrontal areas, putamen, hippocampus and brainstem. Nonpainful stimulation of the trigger zone activated all but three of these structures (SpV, brainstem and ACC). After a successful surgical treatment, activation induced by stimulation of the operated side was confined to S1 and S2. Our data demonstrate the pathological hyperexcitability of the trigeminal nociceptive system, including the second order trigeminal sensory neurons during evoked attacks of CTN. Such sensitization may depend on pain modulatory systems involving both the brainstem (i.e. periaqueductal gray and adjacent structures) and interconnected cortical structures (i.e. ACC). The fact that large portions of the classical 'pain neuromatrix' were also activated during nonpainful stimulation of the trigger zone, could reflect a state of maintained sensitization of the trigeminal nociceptive systems in CTN.

FBS must be identified by the head and neck surgeon and distinguished from the usual postoperative pain. The generally accepted hypothesis is that of sympathetic denervation with parasympathetic secretory hyperactivity, but Horner's sign was present in only 12 of the 17 patients of our series, suggesting that other pathogenic mechanisms may be involved. FBS is difficult to treat, but the pain gradually becomes less severe. The patient must be informed about this rare complication that can impact on postoperative quality of life.

These results demonstrate the osteoconductivity of coral in granular form for vertebral filling. Interestingly, interconnectivity between adjacent bone trabeculae and newly formed bone was restored; however, its mechanical significance remains to be determined. Further investigations are needed to evaluate the efficacy of coral in osteopenic animals and in relieving pain.