title: Separate assessment of gluteus medius and minimus: B-mode or M-mode ultrasound?
abstract: The hip abductors gluteus medius (Gmed) and minimus (Gmin) differ slightly in function and how they are affected by hip joint pathology. A separate assessment of Gmed and Gmin is feasible by ultrasound (US) imaging. B-mode and M-mode US can be used to measure muscle thickness. Two B- and two M-mode scans of Gmed and Gmin thickness were taken in relaxation on 16 asymptomatic volunteers, repeated within 4 days on 11 subjects. Three types of intra-rater reliability of muscle thickness measurements were examined: (1) within-session reliability comparing two scans from the same session, (2) between-days reliability comparing thickness from two scanning occasion within 4 days and (3) reliability of taking thickness measurements by re-measuring the same US scans after 1 week. Thickness measurements on B- and M-mode images provided ICC3,1 >0.96 for within-session reliability. ICC3,k >0.89 for between-days reliability and ICC3,1 >0.85 for re-reading the same scans were estimated. Minimal detectable changes >1.0 mm within-session, >2.4 mm between-days and >1.7 mm for re-reading scans indicated that small thickness changes are not detectable. The investigation suggests a slight advantage for fascia recognition in B-mode and the advantage of visual control of muscle relaxation in M-mode.
authors.affiliation: School of Physiotherapy and Exercise Science, Curtin Health Innovation Research Institute (CHIRI), Curtin University , Perth , Australia and.
authors.forename: Angela V
authors.initials: AV
authors.lastname: Dieterich
authors.forename: Louise
authors.initials: L
authors.lastname: Deshon
authors.forename: Christine M
authors.initials: CM
authors.lastname: Pickard
authors.forename: Geoffrey R
authors.initials: GR
authors.lastname: Strauss
authors.forename: Janice
authors.initials: J
authors.lastname: McKay
mesh_terms: D000328:Adult; D002081:Buttocks; D004576:Electromyography / Q000379:methods*; D005260:Female; D064368:Healthy Volunteers; D006621:Hip Joint / Q000502:physiology*; D006801:Humans; D008297:Male; D009119:Muscle Contraction / Q000502:physiology; D018482:Muscle, Skeletal / Q000000981:diagnostic imaging* / Q000502:physiology; D015588:Observer Variation; D016059:Range of Motion, Articular / Q000502:physiology; D012016:Reference Values; D012494:Sampling Studies; D018608:Ultrasonography, Doppler / Q000379:methods*; D055815:Young Adult
keywords: Hip; muscle; sonography