changes in muscle activity in patients with primary chronic headache

Objective:According to the Global Burden of Disease Study,updated in 2018,headache disorders are the second leading cause in the world and impaired quality of life and lead to reduce daily activity and can be the cause of headache-related disability.So,we desperately need to develop new painless and minimally invasive methods to facilitate diagnosis to improve the quality of headache care.Methods:Our study involved 92 participants over 18 years of age with a diagnosis of primary chronic headache.Among those,36 were with chronic tension type headache,26 were with a chronic migraine,and 30 were healthy participants.All patients were selected according to the criteria of the International Headache Society.Clinical questionnaires,instrumental data,and characteristics of headache episodes were collected from all participants.We evaluated the muscle activity of the pericranial and cervical muscles in patients with chronic headache to compare with healthy participants using Surface electromyography to determine if there is an alteration in muscle activity.Results:Surface electromyography data showed that there was a statistically significant difference in results between the target group and the control group,where patients with primary chronic headache had high amplitude and velocity in the studied muscles on the electromyogram.Among the participants,there was a difference in the intensity of headache attacks on the visual analog scale chronic tension type headache 5.2±1.4,chronic migraine 7.7±1.3,control group 1.6±0.7 and in the frequency of headache attacks per month chronic tension type headache 14.4±1.9,chronic migraine 17.3±2.9,the control group of participants had headache attacks of≤1 per month.Conclusion:We concluded that the patients with primary chronic headaches there are changes in the muscle activity of the pericranial and cervical muscles.In contrast to patients without chronic headaches,which,in turn,the method of surface electromyography may encourage further research in this area.

Vestibular-evoked myogenic potentials recorded from miniature pigs and rats

Objective:To report vestibular evoked myogenic potentials from different recording sites(neck extensor or masseter muscles) in miniature pigs and rats.Methods:Potentials were recorded using 1000 Hz tone bursts from the neck extensor muscle or masseter muscle in normal adult Bama miniature pigs and rats anesthetized with 3%pentobarbital sodium and Sumianxin Ⅱ.Results:At 80 dB SPL,the first positive wave(P wave) of VEMPs was recognizable in 58%of rats with a latency of 6.45±0.23 ms and an amplitude of 1.45±0.49 μV when recorded from the neck extensor muscle,and in 50%of rats with a latency of 6.38±0.34 ms and an amplitude of 1.57±0.35 μV when recorded from the masseter muscle.In miniature pigs,at the same stimulus intensity,P wave was recognizable in 58%of the animals with a latency of 7.65±0.64 ms and an amplitude of 1.66±0.34 μV when recorded from the neck extensor muscle,and in 50%of the animals with a latency of 7.65±0.64 ms and an amplitude of 0.31±0.28 μV when recorded from the masseter muscle.Conclusion:VEMP can be induced from both neck extensor and masseter muscles in the miniature pig and rat.For a given species,the site of recording affects P wave induction rate and amplitude but not latency.Consistency and repeatability analysis suggests that the masseter muscle is a better recording site in miniature pigs while the cervical extensor is a better recording site in rats.For a given recording site,both latency and amplitude of the P wave are slightly greater in miniature pigs than in rats.