Anomalous foramina in the xiphoid process of the sternum: Anatomical considerations and clinical significance

Background and Aims: Sternum is a flat bone which is divided into different parts i.e. manubrium, body and xiphoid process. The xiphoid process is a thin plate of cartilage to which there is no rib attachment. The main aim of the present study was to observe the abnormal foramens in the xiphoid process of the sternum. Design: An osteological study on the sternum to observe the presence of any foramina in the xiphoid process. Methods: Hundred human sterni were collected from the bone repository in Forensic Osteology Research Centre, Chiang Mai University, Thailand. The sternum was studied for any abnormal foramina in the xiphoid process. Appropriate measurements of the foramina were taken. Results: Out of 100 bone specimens of sternum, only 4 specimens exhibited anomalous foramina in the xiphoid process. There was single foramen in 3 specimens. These foramina measured 3.8 mm, 4.11 mm and 10.8 mm as maximum transverse diameter, respectively. The foramina measured 4.61 mm, 4.40 mm 16.89 mm as maximum vertical diameter, respectively. The specimen which exhibited double foramina in the xiphoid process had the upper and lower foramina measuring 4.40 mm and 4.43 mm as the transverse diameter whereas both foramina measured 5.34 mm and 5.43 mm in vertical diameter, respectively. Conclusion: Presence of abnormal foramen in the sternum may mislead radiographic investigations, result in inadvertent injuries during cardiopulmonary resuscitation and sternal biopsies. Anatomical knowledge of abnormal foramina in the xiphoid process may be important for both academic and clinical purpose.