Gross Anatomy Lecture 2.1 Thorax

Front 1

Thorax

Back 1

Region of trunk between neck and abdomen

Front 2

Thoracic Wall

Back 2

Skin, fascia, nerves, vessels, muscle, bones and breast

Front 3

Thoracic cavity

Back 3

Heart, Lungs, Thymus, Distal Trachea, and Esophagus

Front 4

Skeleton of Thoracic Wall

Back 4

Osteocartilaginous thoracic cage

- Sternum

-12 pairs of ribs and costal cartilage

-12 thoracic vertebrae and intevertebral discs

Front 5

Superior thoracic aperture (thoracic inlet)

Back 5

Access for thoracic cavity to communicate w/ neck, measures AP 5cm and 11cm transversly; slopes down and forward. Bounded by T1, 1st ribs/costal cartilage, superior border of manubrium. (see next card for picture)

Front 6

What passes through thoracic aperture (thoracic inlet)?

Back 6

Trachea, Esophagus, Common carotid arteries, jugular veins, subclavian aa & vv., Phrenic and Vagus Nerves, Thoracic Duct

Front 7

Thoracic "Outlet" Syndrome (TOS)

Back 7

Compression at the Superior Thoracic Outlet, involving neuro-vascular bundle (brachial plexus and subclavian vessels) causing parasthesia, numbness, cyanosis, thombosis in upper limb.

Front 8

Inferior Thoracic Aperture (thoracic outlet)

Back 8

Access for thoracic cavity to communicate with abdomen, closed by thoracic diaphram, slopes downward and backward. Bounded by T12, 12th rib and costal margins, xiphisternal joint.

Front 9

Manubrium (sternum)

Back 9

-Jugular (suprasternal) notch

-Clavicular notch

-Manubriosternal Joint

Front 10

Body and Xiphoid Process (sternum)

Back 10

Body

-Costal Notches

-Xiphisternal joint

Xiphoid Process

-At bottom

Front 11

Vertebrae (in general)

Back 11

Body-support weight

Sup &inf articular facets-articulation w/ other vertebrae; restricts movement

Transverse process and spinous process for muscle attachments

Front 12

Thoracic vertebrae (specifically)

Back 12

Costal facets on bodies for articulations with head of ribs

Costal facets on transverse process for articulation w/tubercles of ribs

Long, inferiorly-directly spinous processes

Superior articular facets face posteriorly

Inferior articular facets face anteriorly

Front 13

True Ribs

Back 13

1-7; vertebrocostal ribs, costal cartilage attaches directly to sternum

Front 14

False Ribs

Back 14

8-10, vertebrochondral ribs, costal cartilage attaches to costal cartilage of rib 7

Front 15

Floating Ribs

Back 15

11 &12, no attachment to sternum

Front 16

Typical Ribs (ribs 3-9)

Back 16

See picture

Front 17

Muscles of Thoracic Wall

Back 17

-external intercostal (superficial)

-internal intercostal (middle)

-Innermost intercostal (deepest)

Innervated by intercostal nerve

Front 18

Posterior Thoracic Wall (arteries and veins)

Back 18

v&a&n are found in each intercostal space. Post. intercostal a- direct branch of desc. aorta. Post. intercostal v.-drains into hemiazygos v (l) and azygos v (r)

Front 19

Where do the vessels and nerve lie?

Back 19

Betweem the internal and innermost intercostal muscles

Front 20

Anterior Thoracic Wall

Back 20

Internal thoracic artery and vein, Transversus thoracis, diaphragm, anterior intercostal arteries and veins, internal and innermost intercostals

Front 21

Thoracic Cavity

Back 21

Space w/in thoracic walls.

3 compartments

-2 lateral compartments R&L pulmonary cavities

-1 central compartment MEDIASTINUM

Front 22

Pulmonary Cavities

Back 22

Lungs and pleurae (lining membranes)

Lungs- essential organ of respiration

Pleurae-serous pleural sac consisting of two continuous membrances

Costodiaphragmatic recess- bottom things hanging off.

Front 23

Formation of the pleural layers

Back 23

Balloon represents the innermost layer of pleural cavity before the embryological development of the lung.

Front 24

Parietal Pleurae

Back 24

"outer" lining, lines the inner surface of the thoracic wall and the mediastinum. Consists of 4 parts

Costal,Diaphragmatic

mediastinal

cervical (cupola)

Front 25

Visceral pleura

Back 25

"inner" lining

invests the lungs

cannot be disected from the lung

Front 26

Pleural cavity

Back 26

Potential space between visceral & parietal pleura

Filled with pleural fluid, which acts as a lubricant.

Front 27

Trachea

Back 27

Begins at cricoid cartilage. 16-20 incomplete hyaline cartilaginious rings. Divides into R&L primary bronchi at the level of the sternal angle

Front 28

Carina

Back 28

The division point. It is a keel like projection on the inside; most sensitive area of trachea; last line of defense; carcinomatous lymph nodes widen the carina.

Front 29

Right primary bronchus

Back 29

Wider

Shorter

More verticle

Food and other foreign particles more often go into the right primary bronchus

Front 30

Left primary bronchus

Back 30

Closer to pulmonary trunk and aorta.

Each primary bronchus divides into secondary lobar bronchi and then into tertiary segmental bronchi

Front 31

Trachea cross section

Back 31

Anteriorly and laterally: cartilagenous structure

Posteriorly: Trachealis muscle

Front 32

Trachealis muscle

Back 32

Action: constricts the trachea, allowing for higher velocity of air during coughing

Front 33

Lungs

Back 33

Attach to pulmonary vessels and trachea.

Apex- blunt superior end

Lobes: R lung- larger heavier, 3 lobes (superior (horizontal fissure) middle (oblique fissure) inferior) L lung, 2 lobes (sup&inf)

Front 34

Pulmonary circulation

Back 34

Each segmental bronchus is accompanied by a segmental artery and vein for gas exchange. Thus, each bronchopulmonary segment operates independently and can be surgically removed if diseased.

Front 35

Diaphragm

Back 35

Chief muscle of inspiration. Dome-shaped. Separates thoracic cavity from abdominal cavity

Front 36

Diaphragmatic Apertures

Back 36

Permits structures to pass b/w thorax and abdomen.

Caval opening (IVC)

Esophageal hiatus (Esophagus)

Aortic hiatus (Aorta)

Front 37

Caval opening

Back 37

Inferior vena cava.

Located at the level of disc b/w T8 and T9

Front 38

Esophageal hiatus

Back 38

Esophagus

Located at the level of T10

Front 39

Aortic Hiatus

Back 39

Aorta

Does not pierce diaphragm; passes posterior to median arcuate ligament and anterior to T12.

Front 40

Actions of the Diaphragm

Back 40

Contraction moves dome inferiorly

Pushes abdominal viscera inferiorly

Increases volume of thoracic cavity

Allows air to be taken into the lungs

Diagragm also important in circulation of blood, in abdominal straiing (as in micturition, defecation and parturition) and in weight lifting

Front 41

Muscles of inspirtation

Back 41

Diaphragm

External intercostals

Internal intercostals (medial)

Sternocleidomastoid

Scalenes

Serratus posterior superior and inferior

Levator costarum

Front 42

Inspiration

Back 42

Diaphragm contracts (dome pulls inferiorly, verticle height of thorax increases, intrathoracic pressure decreases)

Ribs elevated (passively during relaxed inspiration, actively during forced inspiration)

Pleural cavities and lungs enlarge (air rushes passively into lungs, not pumped in to)

Abdominal pressure increases due to decreased abdominal volume

Front 43

Muscles of Expiration

Back 43

Normal: Elastic recoil of lungs

Forced: Rectus abdominus, internal intercostals (lateral), External oblique, Internal oblique and transversus abdominus.

Front 44

Expiration

Back 44

Diaphragm & intercostals relax (thoracic volume decreases, intrathoracic pressure increases)

Stretch elastic tissue of lungs recoils (like an inflated balloon releasing its air (air expelled)

Ribs are depressed

Abdominal pressure is decreased

Front 45

Nerves of the Diaphragm

Back 45

Motor Supply: PHRENIC nerves, arise from ventral rami C3-C5

Sensory supply: primarily PHRENIC nerves (centrally) some from intercostal and subcostal nerves (peripherally)

Front 46

Types of pleura and pericardium

Back 46

Acute inflammation of pericardial sac (pericarditis) causes the pericardial rub during auscultation. Advanced cases end up in pericardial effusion of cardiac tamponade.