Liftoff resistance of augmented glenoid components during cyclic fatigue loading in the posterior-superior direction

• Published in: Journal of shoulder and elbow surgery 2013-11, Vol.22 (11), p.1530-1536
• Main Authors: Iannotti, Joseph P., MD, PhD, Lappin, Kyle E., BS, MBA, Klotz, Conrad L., BS, MBA, Reber, Erik W., MS, Swope, Steve W
• Format: Article
• Language: English
• Subjects: Arthroplasty, Replacement - methods; Augmented glenoid components; Biomechanical Phenomena; Compressive Strength; glenoid bone loss; Humans; in vitro study; Joint Prosthesis; mechanical testing; Orthopedics; Prosthesis Design; Prosthesis Failure; Scapula; shoulder osteoarthritis; Stress, Mechanical; total shoulder arthroplasty
• ISSN: 1058-2746; 1532-6500
• DOI: 10.1016/j.jse.2013.01.018

Background and hypothesis Posterior glenoid bone loss is found in a majority of patients with advanced osteoarthritis of the shoulder. In total shoulder arthroplasty, several methods currently exist for management of this bone loss, including the use of an augmented glenoid component. Different augmented glenoid designs would be expected to vary in their resistance to loosening during mechanical bench-top testing. Our hypothesis is that a stepped augmented glenoid component will have less mechanical liftoff than augmented components of varying designs without a step. Materials and methods Four glenoid prototypes articulated with a humeral head were loaded with a 170-lb compressive load and with 4 mm of posterior-superior translation of the humeral head to 100,000 cycles. Anterior glenoid liftoff was measured. Results The stepped glenoid component had significantly lower liftoff values ( P