Thorax Flashcards
Rib parts and articulations and joint names
Head,neck,tubercle, body
Head articulates with respective thoracic vertebrae and the intervertebral disc at the costovertebral joint.
● The tubercle articulates with the transverse process of a thoracic vertebra at the costotransverse joint.
Manubrium notches,joints and rib attachments
manubrium forms the jugular notch at its superior margin; has a clavicular notch, which articulates with the clavicle at the sternoclavicular joint; and articulates with the costal cartilages of ribs 1 and 2.
Body of sternum and xiohoid process
Joints
Rib attachments
What’s the point of attachment of xiphoid process with diaphram called?
The body articulates with the manubrium at the sternal angle of Louis, articulates with the costal cartilages of ribs 2 to 7, and articulates with the xiphoid process at the xiphosternal joint.
● The xiphoid process articulates with the body of the sternum and attaches to the diaphragm and abdominal musculature via the linea alba.
Sternal angle of loius
site of which Main landmarks
e sternal angle of Louis marks the junction between the manubrium and body of the sternum at vertebral level T4. This is the site where rib 2 articulates with the sternum, the aortic arch begins and ends, the trachea bifurcates, and the superior mediastinum ends.
relations of the important venous structures to thoracic cage
Thoracic cage: relations to the important venous structures
Behind the sternoclavicular joints: the brachiocephalic veins begin.
Behind the 1st costal cartilage on the right the superior vena cava begins.
Behind the 2nd costal cartilage on the right the azygos vein ends.
Behind the 3rd costal cartilage on the right the superior vena cava end
1)Thoracic cage communicates with neck through____ what are its 2)boundaries,3) partition and 4)structures that pass through it..?
1) thoracic inlet
2) ant: manubri sterni , post: 1st thoracic vertebra, lat: 1st rib+cartilage,
3) partition: suprapleural membrane( sibsons facia)
4) trachea , oesophagus, apices of lungs and thymus remains
What are nerves that pass through thoracic inlet
1) right and left phrenic nerve
2) right and left vagus nerve
3) right and left sympathetic trunks
4) right and left 1st thoracic nerve
What are larger vessels and muscles that pass through thoracic inlet
Larger vessels: right brachiocephalic trunk 2)left common carotid artery 3) left subclavian artery 4) right and left brachiocephalic vein
Muscles: sternohyoid muscle , sternothyroid muscle , longus colli muscles
Thoracic outlet ,partition, boundries, big vessels and nerves
Thorax communicates with abdomen through thoracic outlet
,partition— diaphram
boundries- ant:xiphisternal joint,post:T12, lat:costal margins
, big vessels-Aorta,inferior vena cava,azygos veins and hemizygos veins
nerves-lesser splanchnic n,vagus n,greater splanchnic n,right phrenic n,sympathetic arch,subcostal n
Viscera and lymphatics that pass through thoracic outlet
Oesophagus ,thoracic duct and lymphatics
What are the levels of diaghragm.right and left….during sitting and lying
Right diaphragm is up to upper border of 5th rib because of liver,left is upto lower border of 5th rib because of heart,it’s level is lowered while standing and sitting , and is raised during sleep or after meal
Innervations of diaghragm
Cervical 3,4,5
Motor:phrenic nerve
Sensory:phrenic nerve (central part)+lower five intercostal nerves (periphery of diaphragm)
Different openings of diaphragm with their level and structures passing through
A)vena caval opening; at level of T8..inferior vena cava+right phrenic nerve
B)oesophageal opening;at level of T10….oesophagus,right and left vagus nerve,left gastric artery ,oesophageal vein
C)Aortic hiatus opening;at level of T12….ATA)aorta,thoracic duct,azygos vein
4 major functions of diaphragm
1) inspiration
2) abdominal straining —> abdominal pressure rises and helps in lowering pelvic contents -micturation,defecation,parturition.
3) weight lifting—>after inhaling and closing glottis—>abdominal pressure rise-which support vertebral column and prevent flexion—>postvertebral muscles helps lifting weight
4) thoracoabdominal pump—>pressure gradient develops due to less pressure in thorax and more in abdomen —>blood comes into RA from IVC and lymph is drained into thoracic duct
Intercostal nerve types and supply
1)upper three intercostal nerves—->intercostal spaces and upper limb
2)typical intercostal nerves—->thoracic wall muscles and cutaneous supply of thorax
3)Thoracoabdominal nerves(T7-T11)—>thoracic wall+abdominal wall muscles +cutaneous supply of thorax and abdomen
Subcostal nerve(T12)—>abdominal wall +skin of buttock
Weighs,borders,lobes,surfaces and fissures of lungs
1)left lungs—>600gm,right one—>700gm
2)3 borders—>anterior,posterior and inferior
3)3 surfaces—> costal surface,mediastinal surface and diaphragmatic surface
4)oblique fissure—>extends from inferior border to upward and backward until it cuts posterior border ,2.5 inches below the apex.
Horizontal fissure—>present only in right lung+extends horizontally on costal surface until meets oblique fissure
5)lobes-right lungs 3 lobes-superior,inferior and middle………left one has two lobes (sup and inf)+lingula {tongue shaped projection below cardiac notch(notch on inferior aspect of LL)}
Arterial and venous supply of lungs
arteries-right bronchial artery-part of third intercostal artrry -left bronchial artery part of descending aorta -pulmonary arteries supply alveoli…..venous supply - bronchial veins drain into azygos and hemizygos veins ..two pulmonary veins leave each lung
Nervous supply of lungs
Ear cough
Vagus -vasodilatation +bronchonconstriction+glandular secretion
Sympathetic chain-vasoconstriction+bronchodilation
Both have afferent and efferent fibers
Ear cough -vagus nerve also supply the tympanic membrane of ear therefore irritation to ear causes cough
1)Contents of roots of lungs and structures passing 2)anterior and 3)posterior to the roots
1)Contents:pulmonary artery +veins..bronchi +bronchial vessels…pulmonary plexus …branchiopulmonary lymph nodes
2)right side-phrenic nerve +sup vena cava
Left side:phrenic nerve
3)right side:vagus nerve
Left side:vagus nerve+descending aorta
Divisions of mediastinum
1) Superior mediastinum
2) Inferior mediastinum
i) anterior mediastinum
ii) middle mediastinum
iii) posterior mediastinum
Superior mediastinum 1)boundaries 2) contents 3)reason for tumours
1) ant:manubri sterni,pos:4 thoracic vertebrae,sup:thoracic inlet,inf:imaginary plane passing from sternal angle to 4th T vertebrae ,on each side medistinal pleura
2) thymus ,large veins ,large arteries,,trachea,oesophagus, thoracic duct, sympathetic trunk
3) large veins are present on right side while large arteries on left side,during î blood flow veins expand thus leaving space on right side for tumours or fluids to project.
Anterior mediastinum 1)boundaries 2)contents
1)ant:body of sternum, pos:pericardium ,sup: imaginary line ,inf:superior surface of diaphragm
2)sternopericardial ligaments
Thymus(lower part)
Internal thoracic artery(small mediastinal branches)
