Computer navigation of the glenoid component in reverse total shoulder arthroplasty: a clinical trial to evaluate the learning curve.

Abstract

Intraoperative computer navigation has been introduced recently to assist with placement of the glenoid component. The aim of this study was to evaluate the learning curve of a single surgeon performing computer navigation of glenoid implant placement in primary reverse total shoulder arthroplasty (RTSA). Following training with the intraoperative computer navigation system, we conducted a prospective case-series study of the first 24 consecutive patients undergoing a primary RTSA with navigation performed by a single surgeon. Surgical times, complications, and accuracy of glenoid positioning compared with the preoperative plan were evaluated. Surgical times were compared with the preceding non-navigated series of 24 consecutive primary RTSA cases. Postoperative 3-dimensional computed tomography scans were performed to evaluate glenoid component version and inclination compared with the preoperative plan. The total surgical time was 77.3 minutes (standard deviation [SD], 11.8 minutes) in the navigated RTSA cohort and 78.5 minutes (SD, 18.1 minutes) in the non-navigated series. A significant downward trend in the total surgical time was observed in the navigated cohort (P = .038), which flattened after 8 cases. No learning curve was observed in deviation of glenoid version or inclination from the preoperative plan. The mean deviation of achieved version from planned version was 3° (SD, 2°), and the mean deviation of achieved inclination from planned inclination was 5° (SD, 3°). Findings from this study suggest that intraoperative computer navigation will not require substantially increased operating times compared with standard surgical techniques. With prior surgeon training, approximately 8 operative cases are required to achieve proficiency in intraoperative computer navigation of the glenoid component.