title: A 3D reconstruction method of the body envelope from biplanar X-rays: Evaluation of its accuracy and reliability.
abstract: The aim of this study was to propose a novel method for reconstructing the external body envelope from the low dose biplanar X-rays of a person. The 3D body envelope was obtained by deforming a template to match the surface profiles in two X-rays images in three successive steps: global morphing to adopt the position of a person and scale the template׳s body segments, followed by a gross deformation and a fine deformation using two sets of pre-defined control points. To evaluate the method, a biplanar X-ray acquisition was obtained from head to foot for 12 volunteers in a standing posture. Up to 172 radio-opaque skin markers were attached to the body surface and used as reference positions. Each envelope was reconstructed three times by three operators. Results showed a bias lower than 7mm and a confidence interval (95%) of reproducibility lower than 6mm for all body parts, comparable to other existing methods matching a template onto stereographic photographs. The proposed method offers the possibility of reconstructing body shape in addition to the skeleton using a low dose biplanar X-rays system.
authors.affiliation: Arts et Métiers ParisTech., LBM/Institut de Biomécanique Humaine Georges Charpak, 151, Boulevard de l׳hôpital, 75013 Paris, France; Université de Lyon, F-69622 Lyon, France; Université Claude Bernard Lyon 1, Villeurbanne, France; IFSTTAR, UMR_T9406, LBMC Laboratoire de Biomécanique et Mécanique des Chocs, F69675, Bron, France. Electronic address: agathe.nerot@ifsttar.fr.
authors.forename: Agathe
authors.initials: A
authors.lastname: Nérot
authors.affiliation: Arts et Métiers ParisTech., LBM/Institut de Biomécanique Humaine Georges Charpak, 151, Boulevard de l׳hôpital, 75013 Paris, France.
authors.forename: Julie
authors.initials: J
authors.lastname: Choisne
authors.affiliation: Arts et Métiers ParisTech., LBM/Institut de Biomécanique Humaine Georges Charpak, 151, Boulevard de l׳hôpital, 75013 Paris, France; Department of Orthopaedic Surgery, NYU Hospital for Joint Diseases, New York, NY, USA.
authors.forename: Célia
authors.initials: C
authors.lastname: Amabile
authors.affiliation: Arts et Métiers ParisTech., LBM/Institut de Biomécanique Humaine Georges Charpak, 151, Boulevard de l׳hôpital, 75013 Paris, France.
authors.forename: Christophe
authors.initials: C
authors.lastname: Travert
authors.affiliation: Arts et Métiers ParisTech., LBM/Institut de Biomécanique Humaine Georges Charpak, 151, Boulevard de l׳hôpital, 75013 Paris, France.
authors.forename: Hélène
authors.initials: H
authors.lastname: Pillet
authors.affiliation: Université de Lyon, F-69622 Lyon, France; Université Claude Bernard Lyon 1, Villeurbanne, France; IFSTTAR, UMR_T9406, LBMC Laboratoire de Biomécanique et Mécanique des Chocs, F69675, Bron, France.
authors.forename: Xuguang
authors.initials: X
authors.lastname: Wang
authors.affiliation: Arts et Métiers ParisTech., LBM/Institut de Biomécanique Humaine Georges Charpak, 151, Boulevard de l׳hôpital, 75013 Paris, France.
authors.forename: Wafa
authors.initials: W
authors.lastname: Skalli
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008297:Male; D011859:Radiography; D012016:Reference Values; D015203:Reproducibility of Results; D051598:Whole Body Imaging / Q000379:methods*; D055815:Young Adult
keywords: Biplanar X-rays; Body envelope; Geometric modeling; Joint center; Reproductibility