BIG PICTURE Thoracic Cavity Flashcards
What is the Thoracic Cavity enclosed by?
- Ribs
- Vertebral Column
- Sternum
How is the thoracic cavity separated from the abdominal cavity?
Diaphragm
What are the 6 components of the rib?
- Head
- Neck
- Tubercule
- Angle
- Costal Groove
- Body
What are the 6 parts to the sternum?
- Jugular Notch
- Clavicular Notch
- Manubrium
- Sternal Angle
- Body
- Xiphoid Process
What is the visceral pleura?
Serous membrane that covers the lung
What are the 7 muscles of the thoracic wall and where do they attach?
- Anterior Scalene m (C3-C6, transverse processes, anterior tubercles)
- Middle Scalene m (C3-C7, transverse processes, posterior tubercles)
- Posterior Scalene m (C5-C7, transverse processes, posterior tubercles)
- Pectoralis Major (clavicle, sternum, bicipital groove of humerus)
- Serratus Anterior (ribs 1-9, vertebral border of scapula)
- Subclavius (1st rib, clavicle in costoclavicular space)
- Pectoralis Minor (ribs 3-5, coracoid process of scapula)
What muscle is used in expiration?
Subcostal mm
What is each of the 7 muscles innervation?
1-3. C3-C6 spinal nerves
- Medial and lateral pectoral nerve (C5-T1)
- Long thoracic nerve
- C5-C6, subclavian nerve from brachial plexus
- Medial pectoral nerve
What is each muscles action?
1-3. Fix 1st and 2nd ribs in forceful inspiration
- Adduct and medially rotate humerus, pulls scapula anteriorly and inferiorly
- Protracts and rotates scapula
- Anchors and depresses clavicle
- Pulls scapula anteriorly and inferiorly
What is the pericardium?
Membrane that encloses the heart
What are the 4 main muscles of respiration and how do their fibers run?
- External Intercostals (inferoanterior fiber direction or “hands in pocket)
- Internal Intercostals (inferoposterior fiber direction)
- Innermost Intercostals (lateral most part of ICS)
- Subcostals (inferoposterior fiber direction)
What does each main muscle of respiration do?
- Elevate ribs and sternum
2. Depress ribs and sternum
What replaces the external/internal intercostals and where?
- External = anteriorly intercostal membrane
2. Internal = posteriorly internal intercostal membrane
How is the innermost intercostals separated from the internal intercostals?
Intercostal V.A.N. (bundle)`
How many ribs (ICS) do the subcostals cross?
2
What are the 4 arteries of the thoracic wall and what are their branches?
- Axillary Artery - laterall thoracic artery, thoracocromial artery
- Subclavian Artery - 1st and 2nd posterior intercostal arterties, soperior thoracic artery
- Thoracic Aorta - posterior intercostal arteries 3-12
- Internal Thoracic Artery - anterior intercostal arteries, musculophrenic artery, superior epigastric artery
What are the intercostal arteries? Do they both have branches? Name them and tell where they supply.
- Posterior Intercostal Arteries:
a) Dorsal Branch
* Spinal branch (spinal cord)
* Medial cutaneous branch (posterior thoracic wall)
* Lateral cutaneous branch (Posterior thoracic wall)
b) Collateral Branch (lateral thoracic wall)
c) Lateral Cutaneous Branch (anterior thoracic wall from lateral mammary branch)
Name 9 major veins in the thoracic cavity.
- Right Internal Jugular Vein
- Right Brachiocephalic Vein
- Right Subclavian Vein
- Internal Thoracic Vein
- Superior Vena Cava
- Accessory Hemiazygos Vein
- Azygos Vein
- Hemiazygos Vein
- Inferior Vena Cava
What is Kyphosis?
Enhanced posterior convexity
What is Lordosis?
Enhanced posterior concavity
What is Scoliosis?
Lateral deviation of the vertebral column
What is Scoliosis?
Lateral deviation of the vertebral column
What spinal cord levels innervate the dermatome landmarks?
Dermatome C4 = Spinal Nerve C4
etc. They all match.
What is referred pain?
Pain felt in a part of the body other than its actual source
What is C5 dermatome?
Clavicle
What are the 7 organs of the thoracic cavity?
- Trachea (air flow, connects larynx to bronchi of lungs)
- Heart
- Esophagus (carry food, liquids, and saliva to stomach)
- Lungs (breathing)
- Bronchi (shuttle air to lungs)
- Thymus Gland (trains and develops T cells)
- Lymph Node (filter lymph and assist immune response)
Is a missing cephalic vein bad? Where can you find?
No; superiorly into deltopectoral groove
What big artery and nerve are in the deltopectoral triangle?
- Thoracoacromial Artery
2. Lateral Pectoral Nerve
What 3 spots does the deltoid attach to?
- Acromion
- Scapular Spine
- Clavicle
What innervates the deltoid?
Axillary nerve (C5-C6)
What does the clavicular part of the deltoid do?
Flex, internally rotate, and adduct the arm at the shoulder
What does the acromial part of the deltoid do?
Abduct the arm at the shoulder
What does the spinal part of the deltoid do?
Extend, externally rotate, and adduct the arm at the shoulder
What are the 3 parts to the pec major?
- Clavicular Part
- Sternocostal Part
- Abdominal Part
What does the Calvicular Part attach?
Medial half of clavicle
Where does the sternocostal part attach?
Sternum and costal cartilages
Where does the abdominal part attach to?
Anterior layer of rectus sheath
Where do all 3 parts of the pec major insert at?
Crest of greater tuberosity of humerus
What do all parts of the pec major work to do?
Adduct and internally rotate arm at the shoulder
What do the clavicular and sternocostal parts do specifically?
Flex the arm at the shoulder and assist in respiration when shoulder is fixed
Where does the pec minor attach?
3rd to 5th ribs and inserts into the coracoid process
What is the pec minor innervated by?
Medial pectoral nerve (C8-T1)
Where is the lateral pectoral nerve?
Just above pec minor
What is the action of the pec minor?
- Draw scapula downward (inferior angle moves posteriormedially)
- Rotate glenoid inferiorly and assist in respiration
What artery does the pec minor delineate?
Axillary artery
What are the 3 branches to the axillary artery?
- Superior thoracic artery
- Thoracoacromial Artery
- Lateral Thoracic Artery
What is collateral circulation?
Alternate circulation around a blocked artery or vein via another path (anterior/posterior IC arteries)
Smaller the artery, smaller the impact.
What is winged scapula?
Laceration of long thoracic nerve
What 2 arteries come together? What is it called?
Anterior/Posterior Intercostal Arteries - Anastemosis (blood flow coming together)
What spinal nerves form the intercostal nerves?
Anterior rami T1-T11
What forms subcostal nerve?
Anterior rami T12
Do branches of intercostal nerves serve with dermatomes?
Yes
What is thoracic outlet syndrome? (TOS)
Group of pathologic conditions that compresses neurovascular structure
What are the 3 categories for TOS?
- Anterior Scalene Syndrome
- Costoclavicular Syndrome
- Pectoralis Minor Syndrome
Where is Anterior Scalene Syndrome and what does it compress?
Location: between anterior and middle scalens
Structure: brachial plexus and subclavian artery
Where is costoclavicular syndrome and what does it compress?
Location: between first rib and clavicle
Structures: brachial plexus, subclavian a & v
Where is pectoralis minor syndrome and what does it compress?
Location: between pectoralis minor and rib cag
Structures: brachial plexus, axillar a & v
Symptoms of sensory nerve compression for TOS?
- Tingling
- Numbness
- Loss of sensation
- Pain (especially in hand)
Symptoms of motor nerve compression for TOS?
Muscle weakness
Symptoms of artery compression in TOS
Decreased strength of radial pulse
Symptoms of vein compression in TOS
Swelling of upper limb
What is normally unnoticed that could cause TOS?
Cervical ribs - could compress subclavian artery
Where is an intercostal nerve bundle?
Costal grooves on the inferior margin of ribs (between innermost intercostals and the internal intercostal s
Where does VAN happen?
When you get away from midline
How do we know when we are more midline?
When they criss cross
What is a smaller bundle?
Collateral neurovascular bundle
How do we do breast location?
O’clock method
What is the female breast and where is it located?
Large glandular tissue sitting out in front of the pec muscles
How does it have free movements? What is it call?
Fascia between pec muscles and base of breast. Retromammary space (breast bed)
What surrounds the nipple?
Areola
What is involved with the areola?
Sebacious glands involved with breast feeding and to prevent chafing
What are the Suspensory (Cooper’s) ligaments?
Within the breast that are folds of fascia that run from dermis to deep dermis and fascia
What forms milk in the breast?
Glandular tissue
How does milk get to the surface of the breast?
- Breast produces milk during lactation
2. Conveyed to Lactiferous duct in radial fashion and part of it in lactiferous sinus
How does majority of milk exit?
Glandular secretions (can take infant away and milk can still shoot out)
Breast Variations
- Retroverted nipple
- Polythelia (accessory nipple)
- Polymastia (accessory breast)
Where can these accesories be?
From axillary fossa to anterior abdomen wall
Innervation of breast
- Intercostal nerves (larger in females)
- Internal thoracic, lateral thoracic, axillary arteries
- Same is true of veins
Medial and lateral mammary
Where do fluids go in lymphatics in the breast?
Lymphatic plexus
What are the routes of metastasis of breast cancer?
- Pectoral Node
- Axillary Node (75% for metastasis
- Parasternal Node
- Abdominal Node
Can cancer spread to the other breast?
Yes, a very small amount.
Where does Cooper Ligament run to?
Dermis; cancer could cause a dimple
What are 3 major signs of breast cancer?
- Skin dimpling
- Peud’orange
- Nipple retraction
Where do afferents run from in axillary lymph nodes?
Lateral quadrant of breast
Where do efferents run from in axillary lymph nodes?
Clavicular nodes than subclavian lymph trunk
Where do afferents from parasternal nodes go?
Medial quadrants of breast, chest wall, upper abdominal wall, upper surface of liver
Where do efferents run from parasternal nodes go?
Bronchomediastanal trunk
Where do afferents form Abdominal nodes go?
Inferior quadrants of breast, liver, abdominal wall, upper surface of liver
Where do efferents run from Abdominla nodes go?
Parasternal and posterior mediastinal nodes
What is the most effective way to see breast cancer?
X-ray mammography
How does breast cancer appear on mammogram?
Large, jagged density