Thoracic plane
Encyclopedia
The thoracic plane or transthoracic plane is a geometric plane used to divide the mediastinum
(the middle section of the chest cavity
) into the superior mediastinum
and the inferior mediastinum
.
The thoracic plane runs through the level of the sternal angle
(the joint between the manubrium
and body of the sternum) and between the intervertebral disc
located between the T4 and T5 thoracic vertebrae
.
The superior mediastinum extends superiorly above the plane, while the inferior mediastinum extends inferiorly. The inferior mediastinum is further divided into the anterior
, middle
, and posterior mediastinum
.
2. The upper margin of the superior vena cava
3. The crossing of the thoracic duct
4. The bifurcation of the trachea
5. The bifurcation of the pulmonary trunk
6. The level of the sternal angle
(angle of Louis)
7. The level of Rib 2 where it attaches to the sternum
8. The body of vertebrae T4
9. The drainage of the azygos vein into the superior vena cava
Mediastinum
The mediastinum is a non-delineated group of structures in the thorax, surrounded by loose connective tissue. It is the central compartment of the thoracic cavity...
(the middle section of the chest cavity
Thoracic cavity
The thoracic cavity is the chamber of the human body that is protected by the thoracic wall ....
) into the superior mediastinum
Superior mediastinum
The superior mediastinum is that portion of the interpleural space which lies between the manubrium sterni in front, and the upper thoracic vertebrae behind.-Boundaries:It is bounded:* superiorly by the thoracic inlet, the upper opening of the thorax...
and the inferior mediastinum
Inferior mediastinum
Inferior mediastinum can refer to:* Anterior mediastinum* Middle mediastinum* Posterior mediastinum...
.
The thoracic plane runs through the level of the sternal angle
Sternal angle
The sternal angle or 'angle of Louis', from the Latin angulus Ludovici is the anterior angle formed by the junction of the manubrium and the body of the sternum in the form of a secondary cartilaginous joint . This is also called the manubriosternal joint or Angle of Louis...
(the joint between the manubrium
Manubrium
The manubrium or manubrium sterni is the broad, upper part of the sternum. Located ventrally with a quadrangular shape, wider superiorly and narrower inferiorly, it articulates with the clavicles and the first two ribs.-Borders:The superior border is the thickest and presents at its center the...
and body of the sternum) and between the intervertebral disc
Intervertebral disc
Intervertebral discs lie between adjacent vertebrae in the spine. Each disc forms a cartilaginous joint to allow slight movement of the vertebrae, and acts as a ligament to hold the vertebrae together.-Structure:...
located between the T4 and T5 thoracic vertebrae
Thoracic vertebrae
In human anatomy, twelve thoracic vertebrae compose the middle segment of the vertebral column, between the cervical vertebrae and the lumbar vertebrae. They are intermediate in size between those of the cervical and lumbar regions; they increase in size as one proceeds down the spine, the upper...
.
The superior mediastinum extends superiorly above the plane, while the inferior mediastinum extends inferiorly. The inferior mediastinum is further divided into the anterior
Anterior mediastinum
The anterior mediastinum exists only on the left side where the left pleura diverges from the mid-sternal line.It is narrow, above, but widens out a little below.-Boundaries:It is bounded:* in front by the sternum* laterally by the pleurae...
, middle
Middle mediastinum
The middle mediastinum is the broadest part of the interpleural space. It is made up of the pericardial sac and its contents.-Contents:It contains:* the heart enclosed in the pericardium* the ascending aorta...
, and posterior mediastinum
Posterior mediastinum
The posterior mediastinum is an irregular triangular space running parallel with the vertebral column.-Boundaries:It is bounded:* anteriorly by the pericardium * inferiorly by the thoracic surface of the diaphragm ....
.
Significant findings at the level of the thoracic plane
1. The start (where the aortic arch comes out of the heart) and end of the arch of the aorta (where the arch of the aorta becomes the descending aorta)2. The upper margin of the superior vena cava
Superior vena cava
The superior vena cava is truly superior, a large diameter, yet short, vein that carries deoxygenated blood from the upper half of the body to the heart's right atrium...
3. The crossing of the thoracic duct
Thoracic duct
In human anatomy, the thoracic duct of the lymphatic system is the largest lymphatic vessel in the body. It is also known as the left lymphatic duct, alimentary duct, chyliferous duct, and Van Hoorne's canal....
4. The bifurcation of the trachea
Vertebrate trachea
In tetrapod anatomy the trachea, or windpipe, is a tube that connects the pharynx or larynx to the lungs, allowing the passage of air. It is lined with pseudostratified ciliated columnar epithelium cells with goblet cells that produce mucus...
5. The bifurcation of the pulmonary trunk
6. The level of the sternal angle
Sternal angle
The sternal angle or 'angle of Louis', from the Latin angulus Ludovici is the anterior angle formed by the junction of the manubrium and the body of the sternum in the form of a secondary cartilaginous joint . This is also called the manubriosternal joint or Angle of Louis...
(angle of Louis)
7. The level of Rib 2 where it attaches to the sternum
8. The body of vertebrae T4
9. The drainage of the azygos vein into the superior vena cava