Bifid Xiphoid Process- A Case Report

The sternum is a flat bone forming the anterior median part of the thoracic skeleton. Xiphoid process is the smallest part of the sternum. It is at first cartilaginous, but in adult it becomes ossified near its upper end. It varies greatly in its morphology and lies in the floor of epigastric fossa. A bifid xiphoid process was observed during routine cadaveric dissection of the pectoral region, which was seen as an everted bulging mass in the epigastric pit between the two costal margins. There is a need for awareness of these findings as they may determine the accuracy of clinical and other procedures in thoracic region.


INTRODUCTION
The sternum is a flat bone forming the anterior median wall of the thoracic skeleton. In shape, it resembles a short sword, made of three parts. The upper part corresponding to the handle is called the manubrium, middle part resembling the blade is called the body and the lowest tapering part forming the point of sword is the process or xiphisternum.
The xiphoid process, which is the smallest and most variable part of the sternum, is thin and elongated. It lies at the level of T10 vertebra. Although often pointed, the process may be blunt, bifid, curved or deflected to one side or anteriorly. It is cartilaginous in young people but more or less ossified in adults, older than the age of 40 years. In elderly people, the xiphoid process may fuse with the sternal body.
Its junction with the sternal body at the xiphisternal joint indicates the inferior limit of the central part of the thoracic cavity projected onto the anterior body wall; this joint is also the site of the infrasternal angle (subcostal angle) of the inferior thoracic aperture.
It is a midline marker for the superior limit of liver, the central tendon of the diaphragm, and the inferior border of the heart. Attachments: to its anterior surface are attached the most medial fibres of Rectus abdominis and aponeuroses of External and Internal obliques, to its lower end the linea Alba and to its border the aponeuroses of internal oblique and Transversus abdominis. To its posterior aspect slips of diaphragm and origin to sternocostalis muscles are attached and it is here related to liver.

Case report:
During the routine dissection of pectoral region in Department of Rachana sharer (Anatomy) of SDM College of Ayurveda and Hospita , Hassan a bifid xiphoid process was observed in an approximately 60 year old male cadaver. The cadaver was without any deformity and well preserved. The dissection was carried out according to cunningham's manual of practical anatomy as follows-A vertical incision over the skin of thorax was given extending from the suprasternal notch to the tip of xiphoid process. The skin was reflected following which the muscles were exposed. The pectoralis major and pectoralis minor muscles were reflected. The complete sternum was visualized along with the xiphoid process.
Following observations were noted;  Bifid xiphoid process was observed, which was deflected from median plane towards either sides  The process was continuous with the sternum and the xiphisternal joint was found ossified  It was observed to be 10 degrees everted anteriorly

Conclusion
There are limited reports on variations of xiphoid process, but it has to be considered. The xiphoid process is variable in its morphology. It may be perforated, bifid, or deflected.
Many people in their early 40's suddenly become aware of their partly ossified xiphoid process and consult their physician about the hard lump in the pit of their stomach (epigastric fossa). Never having been aware of their xiphopid process before they fear they have developed a tumour such as stomach cancer.
Hence a thorough knowledge of the embryology and anatomy of the xiphoid process is important in clinical and surgical practice to make differential diagnosis in case of a suspected mass in epigastric fossa. Since xiphoid process is a highly variable part of the sternum normal variations are to be understood to plan accordingly during various surgical interventions of thoracic region.