Correlation between the retroversion of the humeral head and the orientation of the intertubercular sulcus: a CT scan anatomical study

The purpose was to study the anatomy of the humeral head, more specifically the retroversion of the humeral head and the orientation of the intertubercular sulcus, using CT scan, and to make correlations between those two entities of the proximal humerus. Sixty dry adult humeri from an osteological collection underwent CT scan from the proximal to the distal extremity. The measurements obtained by CT-reformation were recorded by two independent radiologists. We determined the humeral head axis, the transepicondylar axis, the retroversion of the humeral head, and the orientation of the intertubercular sulcus (ITS). Statistical analysis using SPSS determined the Pearson correlation coefficient. The CT scan measurements were similar to those in the literature, and thus allowed us to validate CT scan assessment. Statistical analysis showed a significant reverse correlation [the coefficient of correlation was -0.37 (p = 0.004)] between the retroversion of the humeral head and the orientation of the intertubercular sulcus: the more the retroversion of the humeral head increases, the more the angle of the orientation of the ITS decreases. To the best of our knowledge, this reverse correlation between the retroversion of the humeral head and the orientation of the intertubercular sulcus has never been described. This new anatomical data might be helpful for orthopedic surgery.