The xiphoid process (), also referred to as the ensiform process, xiphisternum, or metasternum, constitutes a small cartilaginous

process A process is a series or set of activities that interact to produce a result; it may occur once-only or be recurrent or periodic. Things called a process include: Business and management * Business process, activities that produce a specific s ...

(extension) located in the inferior segment of the

sternum The sternum (: sternums or sterna) or breastbone is a long flat bone located in the central part of the chest. It connects to the ribs via cartilage and forms the front of the rib cage, thus helping to protect the heart, lungs, and major bl ...

, typically

ossified Ossification (also called osteogenesis or bone mineralization) in bone remodeling is the process of laying down new bone material by cells named osteoblasts. It is synonymous with bone tissue formation. There are two processes resulting in t ...

in adult humans. Both the Greek-derived term ''xiphoid'' and its Latin equivalent, ''ensiform'', connote a "swordlike" or "sword-shaped" morphology.

Structure

The xiphoid process is anatomically situated at the level of the 9th

thoracic vertebra In vertebrates, thoracic vertebrae compose the middle segment of the vertebral column, between the cervical vertebrae and the lumbar vertebrae. In humans, there are twelve thoracic vertebra (anatomy), vertebrae of intermediate size between the ce ...

(T9) and corresponds to the T7 dermatome.

Development

In neonates and young infants, particularly smaller infants, the tip of the xiphoid process may be seen as a palpable lump situated just below the sternal notch. Between the ages of 15 and 29, the xiphoid process typically undergoes fusion with the body of the sternum through a

fibrous joint In anatomy, fibrous joints are joints connected by Fibrous connective tissue, fibrous tissue, consisting mainly of collagen. These are fixed joints where bones are united by a layer of white fibrous tissue of varying thickness. In the skull, the ...

. Unlike the synovial articulation of major joints, this joint does not permit movement. Ossification of the xiphoid process typically occurs around the age of 40.

Variation

The xiphoid process may exhibit natural bifurcation or, in some instances, perforation (referred to as a xiphoidal foramen). These morphological variations are hereditary, which can facilitate the categorization of family members when addressing burial remains. These morphological differences carry no health implications; they simply represent variances in form.

Other animals

In birds, the xiphoid process is an elongated structure, often following the direction of the

keel The keel is the bottom-most longitudinal structural element of a watercraft, important for stability. On some sailboats, it may have a fluid dynamics, hydrodynamic and counterbalancing purpose as well. The keel laying, laying of the keel is often ...

Function

Similar to how the first seven ribs articulate with the sternum, the cartilage within the

celiac plexus The celiac plexus, also known as the solar plexus because of its radiating nerve fibers, is a nerve plexus, complex network of nerves located in the abdomen, near where the celiac trunk, superior mesenteric artery, and renal arteries branch fro ...

attaches to the xiphoid process, reinforcing it, and indirectly connecting the

costal cartilage Costal cartilage, also known as rib cartilage, are bars of hyaline cartilage that serve to prolong the ribs forward and contribute to the elasticity of the walls of the thorax. Costal cartilage is only found at the anterior ends of the ribs, pr ...

to the sternum. The xiphoid process plays a role in the attachment of many muscles, including the abdominal diaphragm, a muscle necessary for normal breathing. Additionally, it serves as an attachment point for the rectus abdominis muscles, commonly known as the "abs."

Clinical significance

During chest compressions in

cardiopulmonary resuscitation Cardiopulmonary resuscitation (CPR) is an emergency procedure used during Cardiac arrest, cardiac or Respiratory arrest, respiratory arrest that involves chest compressions, often combined with artificial ventilation, to preserve brain function ...

(CPR), it is possible to fracture or dislodge the xiphoid process, potentially leading to punctures or lacerations of the diaphragm. Furthermore, inadvertent liver puncture resulting in life-threatening internal bleeding can occur. Xiphoidalgia (xiphodynia) represents a distinctive

syndrome A syndrome is a set of medical signs and symptoms which are correlated with each other and often associated with a particular disease or disorder. The word derives from the Greek language, Greek σύνδρομον, meaning "concurrence". When a sy ...

characterized by sternum-related pain and tenderness. While some sources categorize this disorder as uncommon, others suggest it may be relatively prevalent but overlooked by medical professionals. Xiphoidalgia is a musculoskeletal ailment capable of producing an array of symptoms that may mimic various common abdominal and thoracic disorders and diseases. Symptoms associated with xiphoidalgia may include abdominal pain, chest discomfort, nausea, and radiating pain extending to the back, neck, and shoulders. Activities such as lifting heavy objects or chest trauma may precipitate this musculoskeletal ailment, and symptoms may intensify with bending or twisting. Common therapeutic approaches include anesthetic and steroid injections. The earliest documented case dates back to 1712. Beyond age 40, individuals may become aware of their partially ossified xiphoid process and potentially misinterpret it as an abnormality. In the context of pericardiocentesis, a medical procedure involving the aspiration of fluid from the

pericardium The pericardium (: pericardia), also called pericardial sac, is a double-walled sac containing the heart and the roots of the great vessels. It has two layers, an outer layer made of strong inelastic connective tissue (fibrous pericardium), ...

of the heart, the xiphoid process often serves as an anatomical landmark for guiding the procedure. Final CD

Etymology

The term ''xiphoid'' originates from the Greek word '' xiphos'', which means 'straight sword', bearing a resemblance to the process's tip. The Latin equivalent, ''processus xiphoides'', translates to the xiphoid process.Siebenhaar, F.J. (1850). ''Terminologisches Wörterbuch der medicinischen Wissenschaften.'' (Zweite Auflage). Leipzig: Arnoldische Buchhandlung.Triepel, H. (1910). ''Die anatomischen Namen. Ihre Ableitung und Aussprache. Mit einem Anhang: Biographische Notizen.''(Dritte Auflage). Wiesbaden: Verlag J.F. Bergmann. The writings of the Greek physician

Galen Aelius Galenus or Claudius Galenus (; September 129 – AD), often Anglicization, anglicized as Galen () or Galen of Pergamon, was a Ancient Rome, Roman and Greeks, Greek physician, surgeon, and Philosophy, philosopher. Considered to be one o ...

refer to ''Os xyphoides'', a translation of the Greek phrase ξιφοειδές ὀστοῦν.Liddell, H.G. & Scott, R. (1940). ''A Greek-English Lexicon. revised and augmented throughout by Sir Henry Stuart Jones. with the assistance of. Roderick McKenzie.'' Oxford: Clarendon Press. In this context, ''os'' in

Classical Latin Classical Latin is the form of Literary Latin recognized as a Literary language, literary standard language, standard by writers of the late Roman Republic and early Roman Empire. It formed parallel to Vulgar Latin around 75 BC out of Old Latin ...

and ὀστοῦν in

Ancient Greek Ancient Greek (, ; ) includes the forms of the Greek language used in ancient Greece and the classical antiquity, ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Greek ...

both denote 'bone', while ξιφοειδές signifies 'sword-shaped'.

Additional images

File:Xiphoid process animation.gif, Position of xiphoid process (shown in red) File:Xiphoid process below2.png, Close up. File:Xiphoid_process_-_close-up_-_animation.gif, Shape of a xiphoid process (animation)

References

External links

{{DEFAULTSORT:Xiphoid Process Bones of the thorax