The impact of three-dimensional planning and navigation on augmented baseplate use and screw length in reverse shoulder arthroplasty

Background: Three-dimensional (3D) preoperative planning and intraoperative computer-assisted navigation (CAN) may influence baseplate augmentation and screw fixation in reverse total shoulder arthroplasty (RTSA). This study evaluated how these technologies affect augmented baseplate use and screw length. This is a Level IV retrospective study. Methods: Three hundred primary RTSAs for glenohumeral degenerative conditions (2014-2024) were reviewed. Patients were divided into three groups: (1) 2D-CT planning without CAN (2014-2017, n = 100), (2) early 3D-CT with CAN (2019-2022, n = 100), and (3) recent 3D-CT with CAN (2022-2024, n = 100). Demographics, glenoid morphology, baseplate type, and screw characteristics were compared. Results: Augmented baseplate use was higher in the 3D-CT groups versus 2D-CT (40% and 43% vs. 15%; P < .01) with no demographic or glenoid morphology differences (P > .05). CAN was associated with longer screws when four screws were used (24.6 mm and 25.3 mm vs. 20.8 mm; P < .001) and when comparing the two longest screws (28.5 mm and 27.3 mm vs. 22.9 mm; P < .01). Screw length did not differ between augmented and standard baseplates. Discussion: 3D planning and CAN increased augmented baseplate use and screw length. Equivalent screw lengths between augmented and standard baseplates suggest that augmentation does not compromise fixation, supporting its safe use in appropriately selected patients.