Early results of augmented anatomic glenoid components

Abstract

Background: Augmented glenoid components restore the native joint line and preserve bone in shoulders with posterior glenoid bone loss. The purpose of this study was to compare the clinical and radiographic outcomes of augmented total shoulder arthroplasties (TSAs) vs. case-matched shoulders with standard implants to assess the early performance of a full-wedge augmented glenoid component.

Methods: Between 2010 and 2015, all TSAs using a full-wedge posteriorly augmented glenoid component with a minimum 2-year follow-up from a single institution were retrospectively reviewed. A total of 37 augmented TSAs were matched with 37 control shoulders with unaugmented glenoid components. The primary outcomes were revision and radiographic glenoid lucencies. Secondary outcomes included range of motion (ROM) and patient-reported outcomes (PROs).

Results: Both augmented and standard TSAs produced similar improvements in all ROM and PRO measures. Patients with augmented glenoid components were more likely to have type B2 or B3 deformities (P = .004). At final follow-up, 54% of augmented glenoids showed implant lucencies compared with 46% of control shoulders (P = .5). The mean Lazarus score remained similar between groups (1.5 vs. 1.2, P = .8). When 8° and 16° augmentations were compared, the 16° augmentation demonstrated a significantly higher mean Lazarus score (4.2 vs. 1.1, P = .03). Reoperation rates were similar between groups (5% vs. 3%, P = .6).

Discussion: Patients with posteriorly augmented glenoid components demonstrate similar improvements in ROM and PROs to patients with standard anatomic glenoid components. Radiographic loosening and revision rates were similar. However, a higher failure rate was seen with the 16° full-wedge augmentation, which is no longer used in our practice.

Keywords: B2; Shoulder arthroplasty; TSA; augment; augmented glenoid; bone loss; full wedge; total shoulder arthroplasty.