Prevalence of os acromiale in an indigenous East African population: a computerized tomography scan-based study

Mordicai Atinga,Angela Atinga,Njalalle Baraza,Wachira Joseph Thiong’O,Sarah Wambui

doi:10.4314/aas.v19i1.2

Abstract

Background: Failure of fusion to any of the acromion physes at maturity may lead to an os acromiale. A radiological review into the prevalence of os acromiale in an indigenous East African population was performed using computer tomography (CT) imaging. The study aimed to demonstrate a lower prevalence of os acromiale in an urban population compared with cadaveric studies. Methods: This was a cross-sectional study with consecutive sampling. CT scans of both shoulders obtained for non-shoulder pathology were used for the analysis. CT scanning was performed at a tertiary referral hospital from January 2019 to July 2020. Results: Nine hundred eighty-two CT studies were eligible for the review. There were148 os acromiale identified that were either pre-acromiale or meso-acromiale. The study found a 15% prevalence of os acromiale among an ethnic East African population, of which almost 40% were meso-acromiale and 60% were pre-acromiale, with no meta-acromiale. Conclusion: The prevalence of os acromiale found in this study is similar to that observed in earlier cadaveric studies. 

Highlights

An os acromiale is an anatomical variant wherein there is failure of fusion of the acromion physes [1]
Given the high prevalence reported in the literature [3,10], this study sought to elucidate the prevalence in an indigenous East African population as the surgical management of shoulder pathology accelerates
It was hypothesized that the etiology of os acromiale was environmental, and the incidence of os acromiale would be lower in our urban patient population, who are possibly exposed to less physical strains

Summary

Introduction

An os acromiale is an anatomical variant wherein there is failure of fusion of the acromion physes [1]. Prevalence studies based on cadaveric or radiological assessment have shown a rate between 0.7% and 18%, with the higher rate in black African populations [3–5]. Given the high prevalence reported in the literature [3,10], this study sought to elucidate the prevalence in an indigenous East African population as the surgical management of shoulder pathology accelerates.

Results

Conclusion