Radiological study of the Asian coracoid process and clavicle: Implications for coracoclavicular ligament reconstruction

PURPOSE: Iatrogenic coracoid and clavicle fracture is a known complication of drilling bone tunnels during anatomic coracoclavicular ligament reconstruction (ACCR). This study aims to measure the dimensions of coracoid process and clavicle in an Asian population to evaluate the suitability of drilling coracoid and clavicle tunnels for ACCR in Asians. METHODS: Width measurements of 196 coracoids and 189 clavicles were obtained after reviewing all computed tomography (CT) scans of the shoulder performed over a 6 years period. Coracoid measurements were made on the CT slice which showed the maximum cross sectional width of the coracoid base. Medial to lateral measurements of the coracoid width were taken on an axial view, 4 mm above the identified junction of the coracoid base and glenoid base. Antero-posterior clavicle width was measured through a point directly above the midpoint of the coracoid and perpendicular to the long axis of the clavicle. RESULTS: The overall mean coracoid width was 14.8 mm ± 2.54 mm (range 9.2–23.3 mm) and clavicle width was 17.1 mm ± 2.72 mm (range 11.1–25.3 mm). CONCLUSION: The Asian coracoid process is smaller than its Western equivalent. More research is required to validate this conclusion as no cadaveric studies with equivalent measurement techniques have been performed on Asians. Given the potentially narrower dimensions of the Asian coracoid process, extra precautions are required to minimize the risk of iatrogenic coracoid and clavicle fractures.