Abstract
Introduction: Correct positioning of the glenoid component is an important determinant of outcome in shoulder arthroplasty. We describe and assess a new radiological plane of reference for improving the accuracy of glenoid preparation prior to component implantation – the Glenoid Vault Outer Cortex (GvOC) plane. Methods: One hundred and five CT scans of normal scapulae were obtained. Forty six females and 59 males aged between 22 and 30 years. The accuracy of the GvOC plane was then compared against the current “gold standard” – the scapular border (SB). Measurements of glenoid inclination, version, rotation, and offset were obtained using both the GvOC and SB planes. These were then compared to actual values. Results: The mean difference between version obtained using the GvOC plane and the actual value was 1.8° (−2 to 5, SD 1.6) as compared to 6.7° (−2 to 17, SD 4.3) when the SB plane was used, (p < 0.001). The mean difference between estimates of inclination obtained using the GvOC plane and the actual were 1.9° (−4 to 6, SD 1.6) as compared to 11.2° (−4 to 25, SD 6.1) when the SB plane was used, (p < 0.001). Conclusions: The GvOC plane produced estimates of glenoid version and inclination closer to actual values with lower variance than when the SB plane was used. The GvOC may be a more accurate and reproducible radiological method for surgeons to use when defining glenoid anatomy prior to arthroplasty surgery.
Highlights
Total shoulder arthroplasty (TSA), whether anatomic or reverse, can be a challenging procedure
glenoid rim (GR) plane of points placed at the edge of the articular surface (White Region of interest (ROI) points with black contour), GR centre, and GR superior-inferior axis
B plane (Grey doted area) formed by points (Grey ROI points with black contour) placed on the spine root pf the scapula and on the lateral border of the scapula
Summary
Total shoulder arthroplasty (TSA), whether anatomic or reverse, can be a challenging procedure. Glenoid component malposition can lead to poor outcomes. This being an unsatisfactory range of motion, pain, and an increased risk of loosening – leading to early implant failure and the potential need for implant revision [2,3,4]. Several techniques have been suggested in the literature to address the challenge of achieving an accurate glenoid component position. These include patient-specific instrumentation (PSI), CT-based planning, navigation, and other computer-or robotic assistance. These techniques have shown reliable results in recent studies [5,6,7,8], but are often time-consuming and/or come with significant financial costs attached
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
