The Effect of Lateralization on the Joint Reactive Forces Across a Reverse Total Shoulder Replacement


Lawrence V. Gulotta, MD


Yingxin Gao, PhD
Timothy M. Wright, PhD
Edward V. Craig, MD, MPH
Russell F. Warren, MD

Project Description

Reverse shoulder arthroplasty is successful at eliminating pain and improving function for patients with shoulder arthritis and a dysfunctional rotator cuff. Traditionally, this prosthesis is designed such that the center of shoulder rotation is medial to the glenoid implant so that shear forces are minimized and failures are reduced. Recent studies have suggested that there may be functional benefits to lateralization, such as improved internal and external rotation, better stability, better shoulder contour, and reduced scapular notching. However, the effects of lateralization on the reactive forces across the implant are poorly understood. This study will evaluate the forces across a reverse total shoulder replacement with varying degrees of lateralization. This will be accomplished with a custom-made shoulder simulator that can replicate muscle forces across the joint. Using this simulator, we plan to determine the joint reactive forces across the implant with varying degrees of lateralization. This data will be used to develop a finite element computer model to determine how various glenoid designs can counteract these forces to ensure implant longevity. The student will be responsible for assisting in cadaver dissection and reverse total shoulder implantation, specimen preparation, running of the simulator, data acquisition, data analysis, and preparation of a manuscript. The student will work closely with a surgeon, research engineer and a doctoral student and will have exposure to senior surgeons and scientists. The only requirement for the position is an enthusiasm for the work at hand.

This position has been filled.