Regional anatomy of the thorax

• What is the thoracic cavity enclosed by?

  Ribcage, sternum, vertebrae, diaphragm
• What are the three main compartments of the thoracic cavity?

  • Right Pleural Cavity
  • Left Pleural Cavity
  • Mediastinum
• What does the mediastinum contain?

  Key structures excluding the lungs
• What are the divisions of the mediastinum?

  • Superior Mediastinum
  • Inferior Mediastinum
• What major vessels are found in the superior mediastinum?

  Aortic arch and thymus
• What are the subdivisions of the inferior mediastinum?

  • Anterior Mediastinum
  • Middle Mediastinum
  • Posterior Mediastinum
• What does the anterior mediastinum contain?

  Connective tissue and lymph nodes
• What is contained in the middle mediastinum?

  Heart, pericardium, great vessels
• What structures are found in the posterior mediastinum?

  Esophagus, descending aorta, thoracic duct
• What are the parts of the sternum?

  • Manubrium
  • Body
  • Xiphoid Process
• What does the manubrium articulate with?

  Clavicles and first rib
• How many pairs of ribs are there?

  12 pairs
• What are the types of ribs?

  • True Ribs (1-7)
  • False Ribs (8-10)
  • Floating Ribs (11-12)
• How do true ribs connect to the sternum?

  Directly via costal cartilage
• How do false ribs connect to the sternum?

  Indirectly via cartilage of the rib above
• What is unique about floating ribs?

  They do not attach to the sternum
• How many thoracic vertebrae are there?

  12 vertebrae (T1-T12)
• What do thoracic vertebrae articulate with?

  Ribs via costovertebral joints
• What are the lobes of the right lung?

  • Superior
  • Middle
  • Inferior
• How many lobes does the left lung have?

  2 lobes
• What is the cardiac notch?

  A space for the heart in the left lung
• What are the four chambers of the heart?

  • Right atrium
  • Right ventricle
  • Left atrium
  • Left ventricle
• What are the key vessels associated with the heart?

  • Superior vena cava
  • Inferior vena cava
  • Pulmonary arteries and veins
  • Aorta
• Where is the trachea located in relation to the esophagus?

  Anterior to the esophagus
• What does the trachea bifurcate into?

  Right and left bronchi
• Where is the thymus located?

  In the superior mediastinum
• What happens to the thymus in adults?

  It regresses
• What are the major arteries of the chest?

  • Aortic Arch
  • Thoracic Aorta
• What does the aortic arch give rise to?

  Brachiocephalic, left common carotid, left subclavian
• What are the major veins of the chest?

  • Superior Vena Cava (SVC)
  • Inferior Vena Cava (IVC)
  • Azygos Vein
• What does the superior vena cava drain?

  Blood from head, neck, upper limbs
• What does the inferior vena cava drain?

  Blood from abdomen, pelvis, lower limbs
• What does the azygos vein drain?

  Thoracic wall into the SVC
• What are the muscles involved in respiration?

  • Intercostal Muscles
  • Diaphragm
  • Accessory Muscles (e.g., sternocleidomastoid, scalene)
• What are the layers of intercostal muscles?

  • External Intercostal
  • Internal Intercostal
  • Innermost Intercostal
• What is the primary muscle of respiration?

  Diaphragm
• What openings does the diaphragm have?

  Esophagus, inferior vena cava, aorta
• What is the function of the external intercostal muscles?

  Elevate ribs during inspiration
• What is the function of the internal intercostal muscles?

  Depress ribs during forced expiration
• What is the function of the innermost intercostal muscles?

  Assist in respiration