title: Assessment of fatty degeneration of the gluteal muscles in patients with THA using MRI: reliability and accuracy of the Goutallier and quartile classification systems.
abstract: The purpose of this study was to quantify the performance of the Goutallier classification for assessing fatty degeneration of the gluteus muscles from magnetic resonance (MR) images and to compare its performance to a newly proposed system. Eighty-four hips with clinical signs of gluteal insufficiency and 50 hips from asymptomatic controls were analyzed using a standard classification system (Goutallier) and a new scoring system (Quartile). Interobserver reliability and intraobserver repeatability were determined, and accuracy was assessed by comparing readers' scores with quantitative estimates of the proportion of intramuscular fat based on MR signal intensities (gold standard). The existing Goutallier classification system and the new Quartile system performed equally well in assessing fatty degeneration of the gluteus muscles, both showing excellent levels of interrater and intrarater agreement. While the Goutallier classification system has the advantage of being widely known, the benefit of the Quartile system is that it is based on more clearly defined grades of fatty degeneration.
authors.affiliation: Department of Radiology, Charité-Universitätsmedizin Berlin, Charité Campus Mitte, Berlin, Germany.
authors.forename: Florian
authors.initials: F
authors.lastname: Engelken
authors.forename: Georgi I
authors.initials: GI
authors.lastname: Wassilew
authors.forename: Torsten
authors.initials: T
authors.lastname: Köhlitz
authors.forename: Sebastian
authors.initials: S
authors.lastname: Brockhaus
authors.forename: Bernd
authors.initials: B
authors.lastname: Hamm
authors.forename: Carsten
authors.initials: C
authors.lastname: Perka
authors.forename: und Gerd
authors.initials: uG
authors.lastname: Diederichs
mesh_terms: D000273:Adipose Tissue / Q000473:pathology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects*; D002081:Buttocks; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000473:pathology; D009133:Muscular Atrophy / Q000145:classification* / Q000175:diagnosis* / Q000209:etiology; D009135:Muscular Diseases / Q000145:classification* / Q000175:diagnosis* / Q000209:etiology; D015588:Observer Variation; D015203:Reproducibility of Results; D012189:Retrospective Studies
keywords: classification; magnetic resonance imaging; muscles; muscular atrophy; reproducibility