title: Intramuscular ganglion arising from the acromioclavicular joint.
abstract: We report a case of a 80-year-old White woman presenting with a localized painless swelling in the upper parascapular region of the right shoulder. Ultrasound (US) showed a ganglion arising from the acromioclavicular joint (ACJ) and extending inside the trapezius muscle, together with a massive tear of the rotator cuff (RC). Magnetic resonance imaging (MRI) confirmed the US findings. Ganglia arising from the ACJ are rare and usually associated with massive RC tears. Their intramuscular extension, to the best of our knowledge, has never been reported in the radiological literature and can mimic a tumor.
authors.affiliation: Département de Radiologie, Division de Radiodiagnostic et Radiologic Interventionnelle, Hôpital Cantonal Universitaire de Genève, Rue Micheli-du-Crest 24, CH-1211 Geneva 14, Switzerland.
authors.forename: Xavier
authors.initials: X
authors.lastname: Montet
authors.forename: Maria Pia
authors.initials: MP
authors.lastname: Zamorani-Bianchi
authors.forename: Amir
authors.initials: A
authors.lastname: Mehdizade
authors.forename: Carlo
authors.initials: C
authors.lastname: Martinoli
authors.forename: Stefano
authors.initials: S
authors.lastname: Bianchi
mesh_terms: D000173:Acromioclavicular Joint; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D018482:Muscle, Skeletal / Q000473:pathology; D009135:Muscular Diseases / Q000175:diagnosis* / Q000000981:diagnostic imaging; D013581:Synovial Cyst / Q000175:diagnosis* / Q000000981:diagnostic imaging; D014463:Ultrasonography