Determination of in vivo glenohumeral translation using fluoroscopy and shape-matching techniques

• Published in: Journal of shoulder and elbow surgery Vol. 17; no. 2; pp. 319 - 322
• Main Authors: Nishinaka, Naoya, MD, Tsutsui, Hiroaki, MD, Mihara, Kenichi, MD, Suzuki, Kazuhide, MD, Makiuchi, Daisuke, MD, Kon, Yoshiaki, MD, Wright, Thomas W., MD, Moser, Michael W., MD, Gamada, Kazuyoshi, PhD, Sugimoto, Hideharu, MD, Banks, Scott A., PhD
• Format: Journal Article
• Language: English
• Published: New York, NY Mosby, Inc 01.03.2008; Elsevier
• Subjects: Adult; Biological and medical sciences; Biomechanical Phenomena; Diseases of the osteoarticular system; Female; Fluoroscopy; Humans; Male; Medical sciences; Models, Anatomic; Orthopedics; Range of Motion, Articular; Shoulder Joint - physiology; Tomography, X-Ray Computed; In vivo; Radiodiagnosis; Glenohumeral joint; Shoulder; Rheumatology; Radioscopy; Technique
• ISSN: 1058-2746; 1532-6500
• DOI: 10.1016/j.jse.2007.05.018

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° 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.