title: Validation of three-dimensional models of in situ scapulae.
abstract: A principal challenge in creating accurate models of in situ scapulae is delineating bone from surrounding soft tissues. Computed tomography scans were obtained of both shoulders of 20 embalmed cadavers. Each shoulder was rescanned after repositioning of the cadavers to test for rescan reliability. After scans were complete, all scapulae were excised and stripped of all soft tissue. Thresholding, region growing, and manual processing were used to create computer-generated 3-dimensional (3D) models. Seven anatomic measurements were performed on each scapula and 3D model. Mean differences between corresponding measurements of specimen and model were small (<3 mm). Intraobserver and interobserver reliability for cadaveric measurements and rescan and interobserver reliability for model measurements were all excellent (R(2) = 0.99). Patient positioning was not a significant source of error in obtaining measurements from 3D models. Results from this work verify that accurate and reproducible 3D models can be created from in situ scapulae by use of effective segmentation.
authors.affiliation: Department of Orthopaedics & Rehabilitation, Penn State College of Medicine, Penn State Milton S. Hershey Medical Center, Hershey, PA 17033-0850, USA.
authors.forename: Chris D
authors.initials: CD
authors.lastname: Bryce
authors.forename: Jason L
authors.initials: JL
authors.lastname: Pennypacker
authors.forename: Nikhil
authors.initials: N
authors.lastname: Kulkarni
authors.forename: Emmanuel M
authors.initials: EM
authors.lastname: Paul
authors.forename: Christopher S
authors.initials: CS
authors.lastname: Hollenbeak
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Mosher
authors.forename: April D
authors.initials: AD
authors.lastname: Armstrong
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002102:Cadaver; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D015203:Reproducibility of Results; D012540:Scapula / Q000000981:diagnostic imaging*; D012782:Shoulder / Q000000981:diagnostic imaging; D014057:Tomography, X-Ray Computed