High intraoperative accuracy and low complication rate of computer-assisted navigation of the glenoid in total shoulder arthroplasty

Background: Preoperative planning software with intraoperative guidance technology is increasingly being used to manage complex glenoid deformity in anatomic total shoulder arthroplasty (TSA) and reverse TSA. The aim of this study was to review the intraoperative efficacy and complications of computer-assisted navigation (CAN) surgery for the treatment of glenoid deformity in TSA. Methods: We performed a retrospective review of all TSAs implanted using a single computer navigation shoulder system. All patients underwent preoperative planning with computed tomography-based preoperative planning software. The starting point on the glenoid and the final version and inclination of the central post (cage) of the glenoid component were reviewed on the intraoperative navigation guidance report and compared with these parameters on the preoperative plan for each patient. The intraoperative accuracy of CAN for glenoid positioning was determined by the deviation of the starting point and final position of the central cage drill in the glenoid compared with the preoperative plan. Data regarding intraoperative complications and the number of times the navigation system was abandoned intraoperatively were collected. Results: Atotal of 16,723 anatomic TSAs and reverse TSAs performedworldwide with the aforementioned navigation systemwere included in this review. In 16,368 cases (98%), every step of the navigation procedure was completed without abandoning use of the system intraoperatively. Therewas minimal deviation in the intraoperative execution of the preoperative planwith respect to version (0.6 degrees +/- 1.96 degrees), inclination (0.2 degrees +/- 2.04 degrees), and the starting point on the glenoid face (1.90 +/- 1.2 mm). In this cohort, 9 coracoid fractures (0.05%) were reported. Conclusion and Discussion: This study demonstrates the safety and efficacy of CAN for glenoid implantation in TSA. Future studies should focus on assessing the impact of CAN on the longevity and survival of glenoid components and improving the costeffectiveness of this technology. Level of evidence: Level IV; Case Series; Treatment Study (C) 2023 Journal of Shoulder and Elbow Surgery Board of Trustees. All rights reserved.