title: Determination of in vivo glenohumeral translation using fluoroscopy and shape-matching techniques.
abstract: The purpose of this study was to investigate glenohumeral translation in-vivo during active shoulder abduction in the scapular plane. Three-dimensional (3D) models of 9 shoulders were created from CT scans. Fluoroscopic views aligned to the plane of the scapula were recorded during active arm abduction with neutral rotation. 3D motions were determined using model-based 3D-to-two-dimensional (2D) registration. Humeral translation was referenced to the glenoid center in the superior/inferior direction. The humerus moved an average of 1.7 mm superior with arm abduction, from an inferior location to the glenoid center. The humeral head was centered within 1 mm from the glenoid center above 80 degrees abduction. Variability in glenohumeral translation between shoulders decreased significantly from initial to final arm abduction. Our findings agree with some authors' observations of inferior-to-central translation of the humerus and behavior as a congruent ball and socket. We believe this information will help improve the understanding of shoulder function.
authors.affiliation: Department of Mechanical & Aerospace Engineering, University of Florida, Gainesville, FL 32611-6250, USA.
authors.forename: Naoya
authors.initials: N
authors.lastname: Nishinaka
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Tsutsui
authors.forename: Kenichi
authors.initials: K
authors.lastname: Mihara
authors.forename: Kazuhide
authors.initials: K
authors.lastname: Suzuki
authors.forename: Daisuke
authors.initials: D
authors.lastname: Makiuchi
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Kon
authors.forename: Thomas W
authors.initials: TW
authors.lastname: Wright
authors.forename: Michael W
authors.initials: MW
authors.lastname: Moser
authors.forename: Kazuyoshi
authors.initials: K
authors.lastname: Gamada
authors.forename: Hideharu
authors.initials: H
authors.lastname: Sugimoto
authors.forename: Scott A
authors.initials: SA
authors.lastname: Banks
mesh_terms: D000328:Adult; D001696:Biomechanical Phenomena; D005260:Female; D005471:Fluoroscopy; D006801:Humans; D008297:Male; D008953:Models, Anatomic; D016059:Range of Motion, Articular; D012785:Shoulder Joint / Q000502:physiology*; D014057:Tomography, X-Ray Computed