"The xiphisternum forms a symphysis with the lower end of the sternal body, the so-called xiphisternal joint. This process can ossify at any time after the third year of life, but usually occurs in adulthood after the fourth decade 1."
"The xiphoid is thin and elongated, but its morphology can be quite varied, including being bifid, perforated, broad, curved or deflected to one side 2. The tip of the xiphoid process is located at the level of the T10 vertebra 3. This variability is genetic and thus can be used for the identification of relatives, but otherwise is without clinical significance. The xiphoid can serve as a reference point for performing chest compressions in CPR (cardiopulmonary resuscitation)."