Xiphoid

The xiphoid process, also known as the xiphisternum, is the smallest and most inferior part of the human sternum. It derives from the Greek xiphos meaning sword, reflecting its typically pointed appearance. In early life it is cartilaginous and gradually ossifies and may fuse with the body of the sternum with age.

Anatomically, the xiphoid process is connected to the sternal body by the xiphisternal joint and lies at roughly the level of the T9 to T10 vertebrae. It forms part of the anterior thoracic wall and sits just below the heart and diaphragm, making its position clinically relevant for procedures and manual examination. In slender individuals it is often palpable at the lower end of the sternum.

Development and variation vary widely. The xiphoid process may be slender, triangular, or even bifid (split into two). Ossification begins in adulthood and can proceed slowly; some individuals retain a cartilaginous tip throughout life. Calcification can occur with aging and, in rare cases, may be mistaken for a pathological calcification on imaging.

Clinical significance includes use as an anatomical landmark in procedures and examinations. During cardiopulmonary resuscitation, hand placement is typically on the lower half of the sternum to avoid injuring the xiphoid process and underlying structures. Trauma or sudden force to the chest can fracture the xiphoid, though such injuries are relatively uncommon.