title: Focal myositis--neurogenic phenomenon?
abstract: We report four cases of focal myositis. The patients, three men and one woman, had painful muscle hypertrophy, affecting four different sites. MRI confirmed the muscle enlargement and oedema. Electromyography revealed evidence of acute and chronic denervation in all four cases. Muscle biopsy was available in three and confirmed features suggestive of focal myositis. Based on our patient material, we suggest that chronic nerve irritation, such as compression, can lead to muscle hypertrophy which, when prolonged, provokes fibre necrosis and secondary inflammation. Our finding in four patients having hypertrophy involving four different sites, leads us further to suggest that this may be the common mechanism behind focal myositis.
authors.affiliation: Department of Neurology, Haukeland University Hospital, N-5021 Bergen, Norway.
authors.forename: Hanne Marie Bøe
authors.initials: HM
authors.lastname: Lunde
authors.forename: Geir Olve
authors.initials: GO
authors.lastname: Skeie
authors.forename: Anne K
authors.initials: AK
authors.lastname: Bertelsen
authors.forename: Bjørn
authors.initials: B
authors.lastname: Karlsen
authors.forename: Hrvoje
authors.initials: H
authors.lastname: Miletic
authors.forename: Sigurd
authors.initials: S
authors.lastname: Lindal
authors.forename: Nils J
authors.initials: NJ
authors.lastname: Brautaset
authors.forename: Laurence A
authors.initials: LA
authors.lastname: Bindoff
mesh_terms: D000328:Adult; D000368:Aged; D004576:Electromyography; D005260:Female; D006801:Humans; D006984:Hypertrophy; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000473:pathology*; D009220:Myositis / Q000175:diagnosis* / Q000209:etiology; D011843:Radiculopathy / Q000150:complications / Q000175:diagnosis