A Study on Anatomical Variations of Acromion Process in the Dry Adult Scapulae of South Indian Population

Introduction: Acromion process can be classified according to its morphology into flat (Type I), convex (Type II) and hooked (Type III) (Bigliani et al). The incidence of rotator cuff syndrome has been correlated according to the morphology of acromion process by various authors in different ethnic groups. In this study, we analysed the anatomical variations in the morphology of acromion process among the south Indian population and tried to correlate with the findings of other authors. Material andmethods: 100 dry adult scapulae were used for this study. All the scapulae were measured directly with the help of a vernier calliper and measuring scale. Apart from analysing the shapes of the processes, the following parameters were measured viz. (i) length of acromion (ii) width of acromion (iii) Thickness of acromion. Results: In the present study, it was observed that the shapes of 55% were convex (Type II), 30% were flat (Type I), 15% were hooked (Type III). The average length of the process was 41.63 mm, the average width was 23.11 mm and the average thickness was 9.11 mm. Conclusion: The knowledge of the anatomical variations in acromion process is not only imperative to orthopaedicians in the surgical repair of shoulder cuff pathologies, but also for anthropologists in the understanding of the evolution of bipedal gait and forensic anthropometry.