In vivo fracture of a reverse total shoulder replacement humeral tray: A case report

Abstract

Failure analysis was performed for two humeral tray components which fractured in vivo after only 6 and 9 months. Implant retrieval analysis indicated that the components failed due to fatigue failure initiating from a small radius fillet at the interface of the trunnion and tray regions. Finite element simulations revealed the small radius fillet to have resulted in a large stress concentration and confirmed the possibility for fatigue failure in 6 months. The stress concentration caused by both the small radius fillet and the insufficient tray thickness contributed to the premature fatigue failure of the humeral trays.