This narrative review traces how the glenoid component in total shoulder arthroplasty has evolved. It covers conformity, surface shape, and fixation (cemented, cementless, hybrid). The focus is why the glenoid remains the weak link and how design and technique changes address loosening and glenoid deformity.
When you plan a total shoulder, expect the glenoid to be the part that fails. Loosening is the leading reason for revision, so component choice and technique directly affect longevity.
Default to a cemented all-polyethylene pegged component. Metal-backed cementless designs looked promising but fail more (two-fold higher revision in early data, 20% revision at 3 years in a randomized trial) due to overstuffing, thin polyethylene, stress-shielding, and screw breakage.
Understand the mechanism: eccentric rocking-horse loading concentrates in the superior-posterior quadrant and initiates failure at the implant-cement interface. This is why cementing technique, subchondral bone preservation, and version correction all matter.
Respect the limits of reaming. Retroversion under 12 degrees is correctable, but over 18 degrees is not, and aggressive reaming to force a fit removes the subchondral bone that resists migration. In severe posterior deformity, consider grafting or a posterior-augmented component.
This narrative review traces how the glenoid component in total shoulder arthroplasty has evolved. It covers conformity, surface shape, and fixation (cemented, cementless, hybrid). The focus is why the glenoid remains the weak link and how design and technique changes address loosening and glenoid deformity.
When you plan a total shoulder, expect the glenoid to be the part that fails. Loosening is the leading reason for revision, so component choice and technique directly affect longevity.
Default to a cemented all-polyethylene pegged component. Metal-backed cementless designs looked promising but fail more (two-fold higher revision in early data, 20% revision at 3 years in a randomized trial) due to overstuffing, thin polyethylene, stress-shielding, and screw breakage.
Understand the mechanism: eccentric rocking-horse loading concentrates in the superior-posterior quadrant and initiates failure at the implant-cement interface. This is why cementing technique, subchondral bone preservation, and version correction all matter.
Respect the limits of reaming. Retroversion under 12 degrees is correctable, but over 18 degrees is not, and aggressive reaming to force a fit removes the subchondral bone that resists migration. In severe posterior deformity, consider grafting or a posterior-augmented component.