A gender-based comparison of coracoid and glenoid anatomy: CT analysis and discussion of potential impact on the Latarjet procedure.

BACKGROUND The success of the modified Latarjet procedure depends on proper sizing of the coracoid graft. There is no information available regarding the morphometric relationship between the glenoid cavity and the coracoid process for South African population. This study aims at measuring the relationship between the glenoid and coracoid morphometries and investigates their gender related differences. METHODS Glenohumeral computerized tomography (CT) scans of 100 consecutive patients were considered for this study. Morphometric measurements were performed after aligning the coracoid and glenoid in their optimum orientation. These measurements were performed by 2 independent observers. The ratio between glenoid and coracoid measurements were calculated and statistically compared using Mann-Whitney U test. Intraclass correlation coefficients were calculated to analyze inter-observer reliability. All the statistical tests were performed in SPSS v.26 and power calculations were done in G*Power v.3.1. RESULTS An average intraclass correlation coefficient value of 0.79 suggested that the inter-observer reliability was good. Except for coracoid length, statistically significant (p<0.05) gender differences were observed for all the other morphometries. The coracoid width (16.5±1.4mm vs 14.7±1.4mm) and height (13.6±1.6mm vs 10.5±1.5mm) differed between genders by 1.8mm and 3.1mm respectively. The glenoid AP (25.3±2.9mm vs 23.2±2.4mm) and SI (36.9±1.9 vs 33.7±2.6) measurements differed by 2.1mm and 3.3mm respectively between the males and the females. The ratio between the AP width of glenoid and the coracoid height was also found to be significantly different (p<0.05) between the gender groups. These morphometric ratios for coracoid width (0.66±0.09 vs 0.64±0.08), coracoid height (0.55±0.09 vs 0.46±0.07), differed between genders by 0.02 and 0.09 respectively. CONCLUSION Measurements taken from CT scans showed significant differences between genders in absolute measurements and in the ratio of the coracoid height to glenoid AP distance. This could have implications on the ability of the Latarjet procedure to compensate for bone loss in female patients.