The Thoracic Wall Flashcards
what is the thorax
a truncated dome-shaped structure, formed by the sternum, costal cartilages, ribs and thoracic vertebrae
where does the thorax extend
from the root of the neck to the abdomen
what are the basic boundaries of the thorax
- superior thoracic aperture
- inferior thoracic aperture
- thoracic wall
contents of the thorax
- lungs
- heart
- mediastinum
- trachea
- bronchi
- oesophagus
- vagus and phrenic nerves
- major systemic and pulmonary vessels
another name for the superior thoracic aperture
thoracic inlet
margins of superior thoracic aperture
- superiorly - upper first rib, costal cartilage, manubrium
- posteriorly - 1st thoracic vertebra
what is present between the margins of the superior thoracic aperture
apexes of each lung covered by the suprapleural membrane
what is another name for the suprapleural membrane
sibson’s fascia
superior thoracic aperture function
allows important structures to pass in and out thorax
five important structures that pass through the superior thoracic aperture
- trachea
- oesophagus
- subclavian artery and vein
- common carotid artery
- internal jugular vei
shape and size of superior thoracic aperture
- 5cm in length
- 10cm transversely
- slopes down from posterior aspect to anterior aspect
another name for inferior thoracic aperture
thoracic outlet
what is the inferior thoracic aperture composed of
diaphragm
margins of the inferior thoracic aperture
- T12 posteriorly
- costal margins of ribs 7-12 mediolaterally
- xiphoid process anteriorly
name three important structures that pass through the inferior thoracic aperture
- oesophagus
- descending aorta
- inferior vena cava
name 1
lung
name 2
pleural cavity
name 3
visceral pleura
name 4
parietal pleura
name 5
intercostal vein
name 6
intercostal artery
name 7
intercostal nerve
name 9
collateral branches
name 10
endothoracic fascia
name 11
serratus anterior muscle
name 12
external intercostal muscle
name 13
internal intercostal muscle
name 14
innermost intercostal muscle
name 15
skin
name 16
superficial fascia
four functions of the thorax
- respiration
- protection of vital organs
- conduit
- support for breast tissue
explain respiration as a function of the thorax
movements of the thoracic wall increase/decrease intra-thoracic volume. this results in inspiration and expiration
what vital organs does the thorax protect
- heart and lungs
- abdominal organs - liver, spleen, kidneys
what is the primary function of the thorax
respiration
why are thoracic lines important
for the placement of ecg leads
name the three anterior thoracic lines
- midsternal line
- midclavicular lines
- lateral sternal lines
where does the mid sternal line run
bisects the middle part of the sternum
where do the midclavicular lines run
run vertically from the centre of the jugular notch to the tip of the acromiom of scapula
where do the lateral sternal lines run
lateral margins of sternum
name the two posterior thoracic lines
- midvertebral line
- scapular lines
where does the midvertebral line run
straight down the middle of the spine
clinical consideration for the midvertebral line
scoliosis will cause it to be crooked
where do the scapular lines run
down through the inferior margins of the scapula
name the two lateral thoracic lines
- axillary lines (posterior and anterior)
- midaxillary line
where do the axillary lines run
vertical lines which correspond to the anterior and posterior axillary folds
what are the axillary folds
- frame axilla
- formed anteriorly by lateral border of pec major
- formed posteriorly by the borders of latissimus dorsi and teris major
where does the midaxillary line run
bisects the axillary lines
what is another name for the suprasternal notch
jugular notch
where is the suprasternal notch located
above the manubrium and below the clavicles, at the vertebral disc between T2 and T3
clinical consideration of the suprasternal notch
The superior vena cava passes directly behind the manubrium returning blood from the head and neck - notch means we can measure jugular venous pressure to help form a differential diagnosis of congestive heart failur
another name for the sternal angle
angle of louis
where is the angle of louis located
- at manubriosternal junction - at the vertebral disc between T4 and T5
- It’s the point at which the 2nd rib and costal cartilage attach to the sternum
where is the xiphosternal joint located
at the level of the ninth thoracic vertebra
what is 1
cardiac auscultations
aortic area: second right intercostal space
what is 2
cardiac auscultations
pulmonary area: second left intercostal space
what is 3
cardiac auscultations
erb’s point: third left intercostal space (left sternal border)
what is 4
cardiac auscultations
tricuspid area: fourth left intercostal space (left lower sternal border)
what is 5
cardiac auscultations
mitral area or apex: fifth left intercostal space (midclavicular line)
how many chest leads are there in a 12 lead ECG
6