3D CT-Based Preoperative Planning and Intraoperative Navigation in Reverse Shoulder Arthroplasty: Early Clinical Outcomes.

Background and Objectives: Reverse shoulder arthroplasty (RSA) is an effective surgical procedure for treating end-stage rotator cuff arthropathy, but it is burdened by a relatively high complication rate, mainly due to glenoid component failure. Preoperative planning and intraoperative navigation based on three-dimensional computed tomography (3D CT) scans have proven to be efficient tools for improving the accuracy and stability of the glenoid component. However, this technology is still developing, and there is currently little available research on the subject, especially where clinical outcomes are concerned. The purpose of this retrospective observational study is to report the radiographic and clinical outcomes of a consecutive series of patients that underwent RSA with the use of these new technologies, compared to a standard procedure. Materials and Methods: A consecutive series of 80 patients underwent RSA for shoulder osteoarthritis by a single surgeon at a single institution with a mean follow-up of 41.9 ± 23.6 months (range 24-108) and were divided into two groups according to the surgical technique employed (conventional or navigated surgery), and they were clinically and radiographically assessed at 1, 3, 6, and 12 months after surgery, and then annually. Results: No statistically significant differences were highlighted among the two groups according to complication rate, radiographical glenoid notching, and clinical outcomes. However, a statistically significant difference was observed in screw number and length and surgical time. In the navigated group, fewer screws with longer lengths had been implanted, with a longer surgical time. Conclusions: The use of 3D CT-based preoperative planning and intraoperative navigation is a safe procedure and produces comparable results with respect to standard instrumentation, without an increased risk of complications. It allowed to achieve higher stability of the implant, saving bone stock due to the use of fewer and longer screws than in a conventional procedure. This could also eventually result in a higher longevity of the implant itself.