title: Measuring Femoral Torsion In Vivo Using Freehand 3-D Ultrasound Imaging.
abstract: Despite variation in bone geometry, muscle and joint function is often investigated using generic musculoskeletal models. Patient-specific bone geometry can be obtained from computerised tomography, which involves ionising radiation, or magnetic resonance imaging (MRI), which is costly and time consuming. Freehand 3-D ultrasound provides an alternative to obtain bony geometry. The purpose of this study was to determine the accuracy and repeatability of 3-D ultrasound in measuring femoral torsion. Measurements of femoral torsion were performed on 10 healthy adults using MRI and 3-D ultrasound. Measurements of femoral torsion from 3-D ultrasound were, on average, smaller than those from MRI (mean difference = 1.8°; 95% confidence interval: -3.9°, 7.5°). MRI and 3-D ultrasound had Bland and Altman repeatability coefficients of 3.1° and 3.7°, respectively. Accurate measurements of femoral torsion were obtained with 3-D ultrasound offering the potential to acquire patient-specific bone geometry for musculoskeletal modelling. Three-dimensional ultrasound is non-invasive and relatively inexpensive and can be integrated into gait analysis.
authors.affiliation: Hugh Williamson Gait Analysis Laboratory, Royal Children's Hospital, Melbourne, Australia; Murdoch Childrens Research Institute, Melbourne, Australia; Department of Mechanical Engineering, University of Melbourne, Melbourne, Australia. Electronic address: elyse.passmore@gmail.com.
authors.forename: Elyse
authors.initials: E
authors.lastname: Passmore
authors.affiliation: Department of Mechanical Engineering, University of Melbourne, Melbourne, Australia.
authors.forename: Marcus G
authors.initials: MG
authors.lastname: Pandy
authors.affiliation: Hugh Williamson Gait Analysis Laboratory, Royal Children's Hospital, Melbourne, Australia; Murdoch Childrens Research Institute, Melbourne, Australia; Department of Paediatrics, University of Melbourne, Melbourne, Australia.
authors.forename: H Kerr
authors.initials: HK
authors.lastname: Graham
authors.affiliation: Hugh Williamson Gait Analysis Laboratory, Royal Children's Hospital, Melbourne, Australia; Murdoch Childrens Research Institute, Melbourne, Australia; Department of Mechanical Engineering, University of Melbourne, Melbourne, Australia.
authors.forename: Morgan
authors.initials: M
authors.lastname: Sangeux
mesh_terms: D000328:Adult; D000465:Algorithms; D005260:Female; D005269:Femur / Q000000981:diagnostic imaging*; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012399:Rotation; D012680:Sensitivity and Specificity; D014463:Ultrasonography / Q000379:methods*; D055815:Young Adult
keywords: Femoral torsion; Freehand 3-D ultrasound imaging; Gait analysis