Overview of the Thorax Learning Objectives

Name the boundaries of the thoracic cavity

Superior: Superior Thoracic Aperture

Anterior: Sternum

Posterior: Spine

Inferior: Diaphragm

What are the general contents of the thoracic cavity?

Primary organs of respiratory and cardiovascular systems

What are the different compartments of the thoracic cavity?

Pleural cavities, Inferior Mediastinum, Superior Mediastinum

What is found in the Pleural Cavity?

Lungs

What is found in the Inferior Mediastinum?

Heart

What is found in the Superior Mediastinum?

Trachea, Esophagus, Aortic Arch

What are the components of the thoracic wall?

Skin, Subcutaneous fat, Ribs, Intercostal muscles

Function of Thoracic Wall

Protection of organs, respiration, muscular attachments

What are the three different types of ribs?

True, False, Floatiing

Which ribs are true ribs?

1-7

Which ribs are false ribs?

8-10

Which ribs are floating ribs?

11-12

Describe the general structure of a rib

Head articulates with body of vertebrae, costal tubercle is posterior and articulates with transverse process

Costovertebral Joint

Head of Rib → Vertebral body

Costovertebral Joint Synovial Classification

Plane

Costotransverse Joint

Costal Tubercle → Transverse Process of Vertebrae

Costotransverse Joint Synovial Classification

Plane

Sternocostal Joint

Costal Cartilage → Sternum

Sternocostal Joint Synovial Classification

Plane

Unique landmarks of the first rib

Scalene tubercle on superior edge of 1st rub; scalene tubercle is boundary between the groove for subclavian artery and vein (vein is anterior to the artery)

Unique landmarks of the sternum

Manubrium (Jugular notch, and clavicular facet)
Body (Sternal angle - connection between body and manubrium, costal facets to articulate with ribs)
Xiphoid Process

Attachment of External Intercostal

From: Rib

To: Rib oriented from superior-lateral to inferior medial (down and in)

Action of External Intercostal

Elevation of ribs

Innervation of External Intercostal

Intercostal Nerve (segmental)

Attachment of Internal & Innermost Intercostal

From: Rib

To: Rib oriented from superior-medial to inferior-lateral (down and out)

Action of Internal & Innermost Intercostal

Depression of ribs

Innervation of Internal and Innermost Intercostal

Intercostal Nerve (segmental)

Attachment of Transversus Thoracis

From: Posterior sternum

To: Costal cartilages

Action of Transversus Thoracis

Depression of ribs

Innervation of Transversus Thoracis

Intercostal Nerves (segmental)

Diaphrahm

C3-C5

Attachment of Diaphragm

From: Xiphoid Process, Inner surface of lower ribs and costal cartilages, lumbar vertebrae via the crura

To: Central Tendon

Action of the Diaphragm

Inspiration (negative thoracic pressure by inferior displacement)

Innervation of the Diaphragm

Phrenic Nerve

Explain the relation of the rami communicans to the sympathetic chain ganglia and intercostal nerves

The white and rami communicans travel from the sympathethic chain ganglia to the intercostal nerves

Type of axon found in the white rami

Preganglionic sympathetic

Type of axon found in the gray rami

Postganglionic sympathetic

What is the naming convention of the intercostal nerves (T1-T12)

Named for the intercostal space which they occupy

Major landmark of innervation of the thoracic wall: T4

Nipple

Major landmark of innervation of the thoracic wall: T6

Xiphoid process

Major landmark of innervation of the thoracic wall: T10

Umbilicus

What are the breast nodes of the thoracic region?

Parasternal, Inguinal, Infraclavicular, Axillary, Apical Axillary

What region does the (breast) parasternal node drain?

Medial breast bilaterallyWha

What region does the Inguinal node drain

May drain inferior breast

What region does the infraclaviuclar node drain?

May drain superior breast

What region does the axillary node drain?

Predominant drainage of the breast

What region does the apical axillary drain?

Superior breast and other axillary nodes

What are the parietal nodes of the thorax?

Parasternal, Diaphragmatic, Posterior Mediastinal, Intercostal

What region does the (thiorax) Parasternal Node drain?

Breast, abdominal wall, pleura, liverWha

What region does the diaphragmatic node drain?

Diaphragm, Liver, PleuraW

What region does the posterior mediastinal node drain?

Esophagus, Pleura

What region does the intercostal nodes drain?

Lateral and Posterior Thoracic Wall

What are the visceral nodes of the thorax?

Paratracheal, Pulmonary, Bronchopulmonary, Tracheobronchial

What region does the pulmonary node drain?

Lung

What region does the bronchopulmonary node drain?

Bronchi

What region does the Tracheobronchial node drain?

Trachea, Heart

What lymph node does the Paratracheal node drain?

Tracheobronchial

Thoracic Arterial Supply

Go draw it

Venous drainage of the thorax

Go draw it

Lymphatic Drainage of the thorax

Go draw it