Indian Glenoids Are Elongated and Narrower Compared to Western Glenoids: Morphological Data from a Three-dimensional Computed Tomography-based Assessment of 502 Shoulders

Abstract Introduction: Glenoid morphology varies widely with geography. The traditional implant designs for total and reverse shoulder arthroplasty are based on Western glenoid data. There is a paucity of literature on glenoid dimensions in the Indian population. In the context of rising shoulder arthroplasty usage in our region, the present study, the largest of its kind globally, aims to assess the glenoid morphology of the Indian population using a three-dimensional computed tomography (CT) reconstruction system. Methods: Institutional ethics approval was obtained from the institutional ethics review committee prior to the initiation of the study (June 2021). A consecutive cohort of 251 patients ( n = 502 shoulders) underwent high-resolution CT scans at a tertiary referral center between June 2021 and October 2022. Parameters including glenoid length, anterior-posterior (AP) diameters, the circle dimensions, version, and glenoid inclination were assessed. Results: The male-to-female sex ratio was 1.39:1, with 68% of the population over the age of 50 years. The overall mean glenoid length, mid-AP diameter, and maximum AP diameter were measured at 40.9 ± 3.9 mm, 23.7 ± 02.8 mm, and 25.9 ± 2.7 mm, respectively. Further, the mean circle diameter and surface area were calculated as 24.8 ± 2.4 mm and 4.85 ± 0.93 cm 2 , respectively. Notably, mean values for retroversion, superior inclination, and inferior inclination were determined as 5.34° ± 3.79°, 12.11° ± 5.49°, and 22.71° ± 7.03°, respectively. Conclusion: The present study is the largest CT-based observational study of glenoid morphology globally. The Indian glenoid is narrower and more elongated than the Western glenoid. Smaller glenoid dimensions, particularly in Indian females, underscore the necessity for tailored implant design.