Vol. 11, Issue 4 (2025)

The aim of this study is to determine the shape of the acromion according to age; to correlate the type of acromion with the acromial index and the critical shoulder angle.

Methods: This is a prospective study lasting two months, from 1 June 2019 to 31 July 2019. After obtaining informed consent, subjects aged 40 or under were included, while those with shoulder trauma or shoulder pain were excluded. Acromial morphology was analysed according to Bigliani and Morisson after calculating the subacromial distance, lateral overhang by the acromial index and critical shoulder angle.

Results: 142 shoulders in 85 subjects were selected, with a mean age of 51.14 years and a male predominance with a sex ratio of 1.74. There were 52.11% type I acromions; the mean acromial index was 0.62; the mean critical shoulder angle was 33.42°; there were no type I acromions in the elderly and very elderly. There was a significant association between acromion type, acromial index and critical shoulder angle on the one hand, and between acromial index and critical shoulder angle on the other.

Conclusion: Based on our radiological observations of standard shoulder X-rays, analysis of the acromion allows us to predict the future of the shoulder and, at a minimum, its exposure to the risk of rotator cuff rupture or, conversely, omarthrosis.