Re-evaluating the metal-backed glenoid in anatomic total shoulder arthroplasty

The idea of metal-backed glenoid (MBG) components offers a promising alternative to traditional all-polyethylene (PE), cemented glenoid implants in total shoulder arthroplasty (TSA). Despite the historically high success rate of TSA, challenges such as backside wear, PE debris disease, and significant glenoid bone loss during revision surgeries necessitate the development of improved glenoid component designs. Unlike original designs, the modern MBG components are modular and convertible, exemplified by advancements from companies like Lima, Arthrex, and Zimmer. The ability to exchange PE liners and ultimately to convert to a reverse TSA in the current generation of implants has addressed some early concerns and offers insight into previously elusive solutions for anatomic total shoulder replacements. These more modern MBG components simplify the conversion from anatomic TSA to reverse shoulder arthroplasty, thus shortening the surgery, minimizing blood loss and reducing the complication rates associated with revision surgeries. They also enable correction of glenoid deformities both with respect to glenoid version and glenoid inclination that proven elusive with all PE implants. This paper highlights the design improvements, clinical indications, and future prospects of these components, underscoring their role in enhancing patient outcomes in TSA and hinting that further design developments are needed.