Acromion morphology and morphometry in the light of impingement syndrome and rotator cuff pathology

Abstract

Introduction: Acromion process of the scapula and the subacromial space plays an important role in shoulder impingement syndrome and rotator cuff pathology. The aim is to study the morphological and morphometric parameters of the acromion process of human dry scapula in the South Indian population for its relevance in shoulder impingement syndrome and rotator cuff pathology. Material and Methods: Seventy adult unpaired dry scapulae (35 right and 35 left) of unknown age, gender, and without deformity were studied. The various shapes of acromion process were identified. Parameters such as acromioglenoid (AG) distance, coracoglenoid (CG) distance, coracoacromial (CA) distance, and height of the coracoacromial arch (HtCAA) were measured using a digital vernier caliper. The data were statistically analyzed. Results: The three types of acromion process observed were Type I flat in 57.14%, Type II curved in 40%, and Type III hooked in 2.86%. The mean ± standard deviation of AG distance was 24.9 ± 3.7 mm, CG distance was 22.7 ± 4.2 mm, AC distance was 30.9 ± 5.4 mm, and HtCAA was 19.2 ± 2.7 mm. A significant difference was observed with respect to AG (P = 0.04) and CG (P = 0.0007) between both sides of the scapula. Discussion and Conclusion: Knowledge about the common variant and morphometric dimensions of acromion process can aid to better understanding and planning for the treatment of rotator cuff pathology due to impingement syndrome.