• Thorax is the region between abdomen cavity and the root of neck.
• It forms from thoracic wall, its superficial structures (breast, muscles and
• Function of thorax
1) It provide base for the muscle attachment of upper extremities.
2) It protect for the heart, lungs and visceral organs.
3) It attaches the head, neck, vertebral column and pelvis.
6. Area of thorax
1. Mediastinum in the central compartment of the thoracic cavity located
between the two pleural sacs.it contain most thoracic organs. The
mediastinum is divided into two parts
superior mediastinum: extends upwards. Terminating at the superior
Inferior mediastinum: extends downward. Terminating at the diaphragm
7. The anterior mediastinum
The anterior mediastinum contains no major structures. It accommodates loose
connective tissue and some lymphatic vessels
And internal thoracic vessels.
The middle mediastinum: is the largest subdivision of the inferior
mediastinum.it contains several important organs, vessels, nerves and lymphatic
8. Posterior mediastinum
• It contains number of major organs, blood vessels and nerves. Number of
branches a rise from thoracic aorta in the posterior mediastinum. The major
Posterior intercostal arteries
9. Bones of Thorax
• There are three types of bones in the thorax:
1. The sternum
2. T he ribs
3. The Thoracic spine
1- The sternum
The sternum or (Breast Bones) is a flat bone located at the interior aspect of the thorax. It lies
in the mid-line of the chest and has
10. • The sternum helps protect the internal thoracic viscera-such as :- the heart,
lungs and Esophagus.
Part of sternum
The sternum can be divided in to three parts:- manubrium, Body and
11. The Manubrium
• The manubrium is the most superior portion of the sternum. It is trapezoid
in a shape.
• There is a large fossa lined with cartilage.
• These fossa articulate with a medial end of clavicles, forming the
12. The Body
• The Body is a flat and elongated –the largest part of sternum.
• It articulated with manubrium superiorly (manubriosternal joint)
And the xiphoid process inferiorly (xiphisternal joint).
• The lateral edges of the body are marked by numerous Articular facets.
These articular facets articulate with the costal cartilages of ribs 3-6.
13. The Xiphoid Process
• The xiphoid process is the most inferior and smallest part of the sternum. it
is variable in shape and size, with it is tip located at the level of the T10
• Sawirka !!!!
14. The Ribs
• The Ribs are a set pf twelve paired bones which form the protective ‘cage’
of the Thorax. They articulates with the vertebral column posteriorly, and
terminate anteriorly as cartilage (known as coastal cartilages).
• The ribs protect internal thoracic organs. They also have a role in ventilation;
moving during chest expansion to enable lung inflation.
16. • What are 12 ribs called ?
• Ribs 1-7 are called true ribs (vertebrosternal ribs).
• Ribs 8-10 are called false ribs (vertebrochondral ribs)
• Floating ribs 11-12.
17. The Thoracic spine
• The Thoracic spine is the second segment of the Vertebral column, located
between the cervical and the lumbar vertebral segments. It consists of twelve
vertebrae, which are separated by intervertebral disc.
• The Thoracic spine forms part of the thoracic cage.
• This bony structure helps protect the internal visceral.
• Present in both sexes, but they function in females
• Anterior to the pectoral muscles of the thorax
• Contains mammary glands;
• modified sweat glands that produce milk to nourish
a newborn baby
20. Base:- 2nd to 6th ribs and
-Sternum to mid-axillary line
• Slightly below the center of each breast is a ring of
pigmented skin, the areola, which surrounds the central
conical protruding nipple
• Nipple is located at 4th intercostal space in nulliparous
22. The heart anatomy
• The heart is a muscular double pump with two functions
• Its right side receives oxygen poor blood from
the body tissues and then pumps it to the
• Its left side receives oxygenated blood from
the lungs and then pumps it to the body