title: Morphometry and pathology of the paraspinous muscles in idiopathic scoliosis.
abstract: Muscle biopsies from the apex of both sides of the curve of 31 patients with idiopathic scoliosis showed abnormalities in fiber-type distribution in 68 per cent and in fiber size in 55 per cent. There was no preference for either side. Type 1 fiber predominance was as common as type 1 fiber deficiency. Atrophy occurred in 33 per cent and affected mainly type 1 fibers: atrophy of type 2 fibers was rare. Hypertrophy was limited to type 2 fibers, and occurred in 26 per cent. The strength factor for type 1 fibers exceeded that for type 2. Type 2A fibers were no larger than 2B fibers: there was a large type 2A predominance, more so on the convex side. Most of the muscle changes appear to be secondary and compensatory: none suggests a pathogenesis for the curve.
mesh_terms: D000293:Adolescent; D000328:Adult; D001415:Back; D001706:Biopsy; D002648:Child; D005260:Female; D006801:Humans; D006984:Hypertrophy; D008297:Male; D009132:Muscles / Q000473:pathology*; D009133:Muscular Atrophy / Q000473:pathology; D012600:Scoliosis / Q000473:pathology*