Coracoid Process of Scapula: Morphometric Analysis in South Indian Population

Abstract

Introduction: Shoulder pain in subcoracoid impingement syndrome was due to intrusion of rotator cuff tendons in the coracohumeral space. One of the predisposing factors for subcoracoid impingement syndrome was limited subcoracoid space which causes impingement of lesser tubercle of humerus against the coracoid process to produce pain in the anterior region of shoulder. Coracoid process was also used as graft in Latarjet operation done to treat glenohumeral instability. So, understanding the morphometry of coracoid process is very important for orthopaedic surgeons for various surgical procedures. Aim: To analyse the morphometry of coracoid process, coracoglenoid distance and shape of coracoglenoid space among South Indian population. Materials and Methods: This was a cross-sectional study done between March 2018 to September 2018 on 100 dried human scapulae obtained from the bone bank of Department of Anatomy of Private Medical Colleges in South India. Maximum length, breadth, thickness, height of coracoid process, coracoglenoid distance and maximum width of glenoid cavity were measured in millimetres (mm) using digital vernier callipers with the precision of 0.01 mm. Results: Total of 100 dried human scapulae (51 of right side, 49 of left side) were studied and analysed. The average length of coracoid process was 39.47±3.29 mm. The average breadth of coracoid process was 13.91±1.36 mm. The mean thickness of coracoid process was 8.24±1.003 mm. The mean coracoglenoid distance was 27.19±2.42 mm. Breadth of coracoid represents 57.92% of Glenoid width and thickness of coracoid represents 34.27% of Glenoid width. Most common variety of coracoglenoid space found in our study was round bracket shape which was in 51% of scapulae, followed by square bracket shaped in 30% and fish hooked shaped in 19% of scapulae. Conclusion: Morphometry of coracoid process will be taken into account while treating patients with subcoracoid impingement syndrome. Thickness of coracoid process was always smaller than the breadth of coracoid. Hence, the breadth was taken into account when coracoid process was used as a graft to reconstruct glenoid bone loss in recurrent shoulder dislocation.