Thorcic Wall Flashcards
What kind of bones are ribs?
Elongated & curved flat bones
Which ribs are the true ribs?
1-7 because they are attached directly to the sternum
What pattern do the ribs follow for length and breadth?
Length: increase from 1 to 7 and then decrease
Breadth: decrease from 1 to 12
What ribs are most commonly fractured?
The middle ribs; weakest spot
Which ribs are least likely to fracture?
First and last rib: flail chest
The sternum is made of what 3 parts?
Manubrium (handle)
Stern also body
Xiphoid
A male/female sternum of the same height are compared. What do you find?
The male is twice the size of the female
Where can you find the sternum? (Each part)
Manubrium: T3-T4
Body: T5-T9
Xipgoid: T10/T11
What is the Manubrosternal angle used for?
To find the apex of the heart
What is the most commonly site of the sternum?
The sternum body
What is median sternotomy?
When you cut through the sternum for surgery?
What is interosseous infusion?
Infusion though the chest wall.
What are the typical thoracic vertebrae?
2-8
What are the 4 pectoral muscles?
Pectoralis major
- Pectoralis minor
- Serratus anterior
- Subclavius
What are the intercostal muscles?
External intercostal
- Internal “
- Innermost “
- Subcostal
- Transversas thoracis
Where does the neurovascular bundle pass through?
Lies between the 2nd and 3rd layer (internal and innermost intercostal)
What shape is the superior thoracic aperture?
Kidney
At the thoracic inlet what two tubes occupy the midline?
Trachea and esophagus
What are the boundaries of the inferior thoracic aperture?
Anteriorly: xiphisternal joint
Antero-laterally: costal margin
12th thoracic vertebra posteriorly
11th and 12th rib postero-laterally
What separates the abdominal cavities almost completely?
The diaphragm
Which layer of the epidermis is made up of dead skin cells?
Stratum corneum
What kind of layer is the dermis?
Fibrous layer that contains the terminal branches of cutaneous nerves and vessels
What is the lowest part of the integumentum?
The subcutaneous tissue (hypodermis)
What embryonic layer is the skin derived from?
Ectoderm
What embryonic layer is the hypodermics derived from?
Mesoderm
What does deep fascia form?
Aponeuroses, ligaments, tendons, retincula, joint capsules and septa
What does collagen and elastin provide for deep fascia?
Collagen: strength and integrity
Elastin: extensibility and resilience
What does fascia envelope?
Bones (endosteum and periosteum) Cartilage (perichondrium) Blood vessels (tunica externa) Muscles (epimysium, permysium, and endomysium) Nerves (epineurium, perineuirum, and endoneurium)
What fascia invest the pectoralis minor and is suspended from the clavicle/subclavius?
Clavipectoral fascia
What is the superior part of the clavipectoral fascia? What does it span?
Costócoracoid membrane: attached to the first rib and Coracoid process
What is the lower part of the costocoracoid membrane? What does it support?
The suspensory ligament of axilla: supports the axillary fascia and moves with it in abduction of the arm
In adolescents and young adults what is the sternum connected by?
the three parts are connected by byline cartilage, cartilaginous joints or synchondroses
At what level does the xiphisternal joint lie? What other structures are here?
T9/T10 IVD
T10 IVD: The central tendon of the diaphragm (CTD)/ superior border of liver and inferior border of the heart
Costal margin, infrasternal angle
In the upper 6 or 7 costrotransverse joints what kind of movement is exhibited?
Rotation around a transverse axi
In the lower costotransverse joints (8-10 or 8-12) what kind of movement is exhibited?
Simple gliding/up-and-down movement
Where does the crest of the ribs articulate?
With the IVD between the vertebrae
What kind of ligament hold together the costo-transverse joint?
Synovial joint made of 3 parts: the capsule of this joint is thin but reinforced by costo-transverse proper, superior costo-transverse and inferior costo transverse ligaments
Innervation of pectoralis major
Medical and lateral pectoral nerves
Innervation for pectoralis minor
Medial pectoral nerve
Innervation for serratus anterior
Long thoracic nerve (C5-7)
Innervation for subclavius
Nerve to subclavius (C5-6)
Function of pectoralis major
Flexión, addiction and medial rotation at the glenohumeral joint
Function of pectoralis minor
Pulls tip of should down; profits scapula
Function of serratus anterior
Protraction and rotation of scapula; keeps medial border and inferior angle of scapula opposed to thoracic wall
Function of subclavius
Pulls tip of should down; pulls clavicle medullary in order to stabilize the sternoclavicular joint
What is the innervation to the thoracic wall?
Anterior primary rami of spinal nerves T1-T12.
Both typical and atypical intercostal nerves carry post-ganglionic sympathetic autonomic fibers to the trunk and limbs
Which Intercostal nerves are typical?
T3-T6
What makes an intercostal nerve typical?
Run through appreciate intercostal space, gives off the lateral cutaneous branch in mid-axillary and ends as the anterior cutaneous branches.
What may be injured in a thoracostomy procedure?
Small collateral branches that run along the superior border of the lower limb (giving off from intercostal nerves)
What makes T1-T2 intercostal nerves atypical?
They contribute to the brachial plexus
What makes T7-T12 intercostal nerves atypical?
They continue as thoraco-abdominal nerves that supply the parietal peritoneum, muscles, and integumentum of antero-lateral abdominal wall
Where do the vessels that supply the thoracic wall originate from?
The descending thoracic aorta and internal thoracic arteries
What movements change the vertical diameter of the thoracic cage?
Up and down movements of the thoracic diaphragm and the serratus posterior muscles.
What movements change the A-P diameter of the thoracic cage?
The upper 6 costotransverse joints
This is called the pump-handle movement
What increases the transverse diameter of the thoracic cage?
The lower 6 ribs
This is known as the bucket handle movement
What muscles are involved in inspiration?
- Thoracic diaphragm
- Intercostal/subcostal muscles
- Serratus posterior muscles
What congenital or acquired conditions may affect the thoracic outlet?
Cervical ribs
Muscle hyperthrophy
Tumors (aneurysm and tumors of the lung apex)
On what muscles does the breast sit?
2/3 sits on pectoralis major and 1/3 on serratus anterior
What are the 3 components of the breast?
- fat
- Fibrous tissue
- Glandular tissue
What ligament can cause an orange peel appearance on the breast when involved in cancer?
Suspensory ligament of cooper ( part of the fibrous tissue)
What are the lobes (15-20) of the breast drained by?
Lactiferous ducts
Where does most cancer of the breast originate and what does it cause?
Epithelium of lactiferous duct causing an inversion of the nipple
Where is the retromammary space located and of what use is it clinically
Between the breast and the muscles it sits on
It’s used in plastic surgery
Where does most lymph drainage occur?
Into the axillary lymph nodes
What are the 5 groups of axillary lymph nodes associated with vessels?
- Apical (medial side of axillary vessels in the region of the first part of A)
- Central (second part of AA)
- Pectoral (lateral thoracic artery)
- Subscapular (subscapular vessels)
- Humeral (postero-medially)
What axillary lymph nodes are not associated with vessels?
Rotters nodes
What axillary lymph node receives lymph drainage from 4 others? 3 others?
4: apical
3: central
What axillary lymph node drains the anterior wall especially the breast?
Pectoral
What axillary lymph node drains the posterior wall?
Subscapular lymph nodes
What axillary lymph node drains the upper limb, except lymph carried by lymphatics that accompany the cephalon vein?
Humeral
What lymph node is the gateway to metastasis of breast cancer?
Rotter nodes
How do rotters node help spread cancer?
By bypassing the axillary nodes
What is the principle muscle of inspiration?
The diaphragm
Why does the supero-lateral quadrant of the breast have the most glandular tissue?
Because it has an axillary extension (axillary tail of spence)
*also the site of most tumors of the breast
What are the 4 pectoral muscles?
- Pectoralis major
- Pectoralis minor
- Serratus anterior
- Subclavius
What are the intercostal muscles?
- External intercostal
- Internal intercostal
- Innermost intercostal
- Subcostal
- Transversas thoracis
How does the clavicle relate to the lung apex and brachial plexus?
Lung apex superiority and cords of brachial plexus posteriorly
Where do the true ribs usually fracture at?
At their angle
What is a fail chest?
A rib fracture in two sites creates a middle segment that floats. It is sucked in in inspiration ad pushed out in expiration (unstable chest wall)
What clinical significance does a flail chest have?
Hypoventilation
Unstable chest wall
Respiratory insufficiency
During a thoracocentesis procedure by an amateur, what part of the neuro-vascular structure is most vulnerable?
The intercostal nerve
What are some characteristics of shingles?
- Follows dermatome levels of dorsal root ganaglia (sensory neuropathy)
- Stress/elderly
- Sharp burning dermatome pain
- Red, agonizingly painful vesicular eruptions
What is sibsons fascia?
The suprapleural membrane
What s Horner syndrome?
Damage to the sympathetic trunk causes (on same side)
Ptosis (weak droopy eyelid)
Anhidrosis (decreased sweating)
Miosis (contracted pupil)
Enopthalmos (inset eyeball)-w/ or without
What are the two nerves vulnerable in mastectomies?
Long thoracic and Thoracodorsal
What are the 6 branches of the internal thoracic artery?
- Pericardiacophrenic
- Anterior intercostal
- Superior epigastric
- Musculophrenic
- Anterior intercostal (7-9)
- Phrenic branches
What artery is used for CABG?
Internal thoracic artery
What artery compensates for internal thoracic when it is removed?
Inferior epigastric
Where is each part of the heart heard?
Mitral valve: L 5th intercostal MC
Pulmonary valve: medial 2nd L intercostal space
Aortic valve: M second right intercostal space
Right AV:Right half of the body of the sternum
