title: Changes in muscle fiber cross-sectional area and concentrations of Na,K-ATPase in deltoid muscle in patients with impingement syndrome of the shoulder.
abstract: Disturbances of the stabilizing musculature are an important factor in painful shoulders. The important changes in the rotator cuff muscles are well established, but less attention is put on possible disturbances of the deltoid muscle. This study investigated the effect of shoulder impingement on muscle fiber cross-sectional area and the Na,K-pump concentration of the deltoid muscle. The study included six patients with impingement syndrome. Biopsies were taken from the affected and unaffected sides. The muscle fiber cross-sectional area and the Na,K-ATPase concentration was measured. There were significant decreases (p < 0.05) in cross-sectional area of type 1 and type 2 fibers of the affected deltoid muscle of 25 and 18%, respectively. The Na,K-pump concentration of the affected muscles was reduced by 26.6% (p < 0.05).
authors.affiliation: Department of Physiology, University of Tromsø, Norway.
authors.forename: G
authors.initials: G
authors.lastname: Leivseth
authors.forename: O
authors.initials: O
authors.lastname: Reikerås
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009132:Muscles / Q000033:anatomy & histology / Q000737:chemistry* / Q000473:pathology; D009408:Nerve Compression Syndromes / Q000150:complications / Q000473:pathology / Q000503:physiopathology*; D010146:Pain / Q000209:etiology; D016059:Range of Motion, Articular; D017006:Rotator Cuff / Q000503:physiopathology; D000070636:Rotator Cuff Injuries; D012782:Shoulder / Q000033:anatomy & histology / Q000294:innervation; D012785:Shoulder Joint / Q000503:physiopathology; D000254:Sodium-Potassium-Exchanging ATPase / Q000032:analysis*
chemical_list: D000254:Sodium-Potassium-Exchanging ATPase