A Closer Look at the Sternum
The sternum, commonly referred to as the breastbone, is a flat bone situated at the front and center of the chest. It is a key part of the rib cage and protects the organs within the thoracic cavity. The bone has a T-like shape and is palpable under the skin in the upper chest.
The Three Anatomical Parts of the Sternum
The sternum consists of three distinct sections:
- Manubrium: This is the broadest, uppermost part, resembling a handle. It connects with the collarbones (clavicles) and the first pair of ribs.
- Body: The central and longest section, sometimes called the blade, provides points for the cartilage of the third through seventh rib pairs.
- Xiphoid process: This is the smallest and lowest part, pointed and mainly cartilaginous, ossifying with age. It is an attachment site for muscles, including the diaphragm.
The Function and Importance of the Breastbone
The primary role of the sternum is to safeguard the vital organs in the chest like the heart and lungs. It forms the front of the rib cage, offering protection to the entire thoracic area.
The sternum also provides structural support and attachment points for several anatomical features:
- Ribs: Most ribs attach to the sternum through costal cartilage, allowing chest expansion for breathing.
- Clavicles: The collarbones join the top of the sternum at the manubrium.
- Muscles: Various muscles, including the pectoralis major and diaphragm, connect to the sternum.
Common Health Issues Related to the Sternum
The sternum, while strong, can be affected by certain conditions:
- Costochondritis: Inflammation of the cartilage linking ribs to the sternum, a frequent cause of localized chest pain and tenderness.
- Sternal Fracture: A break in the sternum bone, typically from significant impact such as a car accident.
- Pectus Deformities: Congenital conditions like Pectus excavatum (sunken sternum) and Pectus carinatum (protruding sternum).
Mediastinum: The Space Behind the Breastbone
The area behind the sternum is called the mediastinum, the central chest compartment between the lungs. It contains the heart, major blood vessels, esophagus, trachea, and thymus gland. This space is crucial for understanding the anatomy in the middle of your chest.
Sternum Pain vs. Heart Attack Pain
It is important to differentiate sternum pain from a heart attack, though medical advice is always needed for chest pain. A comparison is provided below:
| Feature | Sternum Pain (Musculoskeletal) | Heart Attack Pain |
|---|---|---|
| Onset | Often sudden, related to movement or injury. | Can start gradually and last minutes. |
| Location | Central chest and ribs, possibly spreading. | Squeezing or pressure in the chest center, potentially radiating to arms, neck, jaw, or back. |
| Sensation | Sharp, stabbing, or tender. | Crushing, tightness, or pressure. |
| Accompanying Symptoms | May include localized swelling or warmth. | Can involve shortness of breath, nausea, cold sweats, or dizziness. |
| Relief | Often relieved by rest or anti-inflammatories. | Not relieved by rest; a potential emergency. |
Conclusion
The bone in the middle of your chest is known as the sternum or breastbone, a vital, flat, T-shaped component of the skeleton. It offers essential protection to internal organs and anchors the ribs and collarbones. Understanding its structure, function, and related issues is beneficial for comprehending your body. For more information on sternum anatomy, refer to the Cleveland Clinic on Sternum Anatomy. Always consult a healthcare provider for any persistent or severe chest pain.
