Correlation of Coracoid Thickness and Glenoid Width An Anatomic Morphometric Analysis

Background: The coracoid has been widely used as a graft to reconstruct anterior glenoid bone defects, as described by the Latarjet and Bristow procedures, with successful results. Nevertheless, at the present, there are no studies correlating the size of the coracoid graft and its relation to the glenoid. Purpose: To assess the mediolateral (M-L) and anteroposterior (A-P) thickness of the coracoid process as well as the widest anterior-to-posterior glenoid distance (glenoid width) and to analyze the correlation between these measurements, while comparing these with the A-P coracoid process thickness. Study Design: Descriptive laboratory study. Methods: Sixty-one unpaired, adult human cadaveric scapulae were evaluated. Three examiners performed 3 independent measurements of the largest M-L thickness of the coracoid process and also the widest anterior-to-posterior distance of the glenoid. The A-P coracoid process thickness was also measured to compare for correlations with M-L coracoid thickness. Results: The glenoid width was 26.38 +/- 2.69 mm (range, 20.03-32.35 mm), and the M-L coracoid thickness was 14.51 +/- 1.90 mm (range, 9.60-19.31 mm). Calculating the ratio between the M-L thickness of the coracoid and glenoid width, we observed that the coracoid represented 43% to 70% of the glenoid width (54% on average). The A-P coracoid process thickness was 8.37 +/- 0.93 mm (range, 6.61-9.76 mm), representing 31% of the glenoid width on average. Conclusion: A strong positive and statistically significant relationship between the coracoid process M-L thickness and the anterior-to-posterior glenoid width exists; the coracoid represents, on average, 54% of the glenoid width.