In order to quantify the physical impairments associated with different types of headache, 77 subjects belonging to four different groups (postmotor vehicle accident cervicogenic headache subjects, cervicogenic headache subjects nontraumatic, migraine patients and control subjects) were evaluated using the following variables: posture, cervical range of motion, strength of the neck flexors and extensors, endurance of the short neck flexors, manual segmental mobility, proprioception of the neck, and pain (McGill Pain Questionnaire and the skin roll test). The results of this study showed that postmotor vehicle accident cervicogenic patients have significantly limited active cervical range of motion (in flexion/extension and rotations), present decreased strength and endurance of neck flexors and decreased strength of the extensor muscles. Our results suggest that there are enough differences between the postmotor vehicle accident and nontraumatic cervicogenic headache subjects to warrant caution when analysing the data of these two subgroups together, as several studies have done in the past. The onset of headache is therefore an important variable that should be controlled for when attempting to characterize the physical impairments associated with cervicogenic headache.

Patients with chronic cluster headache or patients with episodic cluster headache whose headaches are uncontrolled on conventional therapy do not appear to gain therapeutically from the addition of melatonin to their usual treatment regimens. It is perhaps the phase-shifting properties of melatonin that mediate its effect in patients with episodic cluster headache, and it may be necessary to treat from the beginning of the cluster bout to reset the circadian pacemaker, thus producing a more positive outcome.

The aim was to evaluate the test-retest reliability of the French translation of the Migraine Disability Assessment (MIDAS) and Headache Impact Test (HIT)-6 questionnaires as applied to episodic and chronic headaches and to assess the correlation between these two questionnaires. The MIDAS and HIT-6 questionnaires, which assess the degree of migraine-related functional disability, are widely used in headache treatment clinics. The French translation has not been checked for test-retest reliability. MIDAS involves recall, over the previous 3 months, of the number of days with functional disability with regard to work and to home and social life. HIT-6 involves a more subjective and general assessment of headache-related disability over the previous 4 weeks. We expect that there may be greater impact recall bias for chronic headaches than for episodic headaches and considered it important to be able to determine if the reliability of these questionnaires is equally good for these two patient populations. Given that both questionnaires have the same objective, that of assessing headache impact, it was thought useful to determine if their results might show a correlation and if they could thus be used interchangeably. The study was approved by an external ethics committee. The subjects were patients who regularly visit the Clinique de la Migraine de Montréal, which specializes in the treatment of headaches. The MIDAS and HIT-6 questionnaires were completed by the patients during their regular visit. Twelve days later, the same questionnaires were mailed with a prepaid return envelope. Sixty-five patients were required in both the episodic and chronic headache groups, assuming an 80% questionnaire return rate. One hundred and eighty-five patients were enrolled, and 143 completed the study, 75 with episodic headaches and 68 with chronic headaches. The questionnaire return rate was 78.9%. On average, questionnaires were completed a second time 21 days after the first, with a median of 19 days. The Shrout-Fleiss intraclass correlation coefficients for MIDAS and HIT-6 were, respectively, 0.76 and 0.77 for episodic headaches and 0.83 and 0.80 for chronic headaches. The Pearson correlation coefficient between the MIDAS and HIT-6 questionnaires was 0.48 for episodic headaches and 0.58 for chronic headaches at the first compilation and 0.42 and 0.59 at the second compilation. The test-retest intraclass correlation of the French versions for both MIDAS and HIT-6 questionnaires indicates moderate reliability for episodic headache and substantial reliability for chronic headache. The correlation between the MIDAS and HIT-6 questionnaires is weak for episodic headaches, but approaches a level of 'good' for chronic headaches.

Outpatient intravenous DHE is a safe treatment. It is useful for refractory cluster headache, is more effective for the episodic form than the chronic form, and has a rapid onset of action. It did not change the evolution of the episodic form, but it did appear to induce remission in the chronic form or transform it to the episodic form. We advance a hypothesis to explain this.

Greater occipital nerve blockade for cluster headacheDear Sir I read with great interest the article of Peres et al. (1) on the effect of 'Greater occipital nerve blockade for cluster headache' and a recent letter to the editor (2). There is more precision in a subsequent publication by Dr M. Anthony (3) on the effect of blockade of the greater occipital nerve. He injected local anaesthetic during cluster attack on 20 patients and headache stopped for 16 of them. He injected local anaesthetic into 10 of the 20 patients outside attack and headache returned to 10 of them in the next 24 h. He injected depomedrol (160 mg, i.m.), the same dosage as he injected around the occipital nerve, in 10 patients and headache returned to 10 of them. This information does not give definite proof of the positive effect of occipital nerve blockade in cluster headache but we get closer than what is suggested in the letter.