High Prevalence of Sternal Foramen: Quantitative, Anatomical Analysis and its Clinical Implications in Acupuncture Practice

The aim of our study was to verify the prevalence of the sternal foramen in adult cadavers and dry bones, as well as to determine its exact localization and relation to acupuncture points. One hundred eighty sternums fixed and contained in 10% formaldehyde solution were examined, of which 100 were dry bones and 80 belonged to adult cadavers. The morphometric measures were expressed in millimeters when measuring the length: 1) from jugular incision to the foramen (JI-F); 2) from sternal angle to the foramen (EA-F); 3) from xiphoid process to the foramen (XP-F). Statistical analysis was performed to compare expected vs obtained foramina frequency, using Fisher's test (p <= 0.05 was considered significant). The results showed 16.6% sternal foramina, significant higher than expected (p <= 0.0248). Of the 30 foramina, 53.3% were found in cadavers, of which one was a woman, and 46.7% sternums were found in dry bones. Of the cadavers with sternal foramen, 10 foramina were at the 5th sternochondral articulation level and 6 foramina at the 4th sternochondral level. Of the 14 analyzed dry bones, 9 foramina were at the space between the 4th and the 5th costal pit level and 5 foramina were at the 5th costal pit level. The mean +/- SD (mm) total length of the sternums was 151.8 +/- 34 and the measures H-F, EA-F, and XP-F were, respectively, 103.8 +/- 22.1mm, 65.6 +/- 15mm and 46.9 +/- 15mm. Knowledge of this occurrence is important to avoid serious heart injury by needle insertion, especially as this area holds a commonly used acupuncture point and sternal puncture.