It rests at the 10th thoracic vertebra. It is the tiniest and lowest part of the sternum. Unlike the other two parts of the sternum namely manubrium and body, there are costal cartilages and ribs that are attached to the xiphoid process.1  Attached to the anterior surface of the xiphoid process are the anterior costoxiphoid ligament and a section of the rectus abdominis muscle.t rests at the 10th thoracic vertebra. It is the tiniest and lowest part of the sternum. Unlike the other two parts of the sternum namely manubrium and body, there are costal cartilages and ribs that are attached to the xiphoid process.