Module 1: The Thoracic Region Flashcards
What does the diaphragm separate
-thoracic and abdominal cavities
Right dome of diaphragm
-can rise up to level of upper border of rib 5
Left dome of diaphragm
-can rise up to level of lower border of rib 5
Central tendon of diaphragm
-where peripheral muscular fibres of diaphragm attach to inferior margin of thoracic cage and lumbar vertebrae
Right crus of diaphragm
-muscular extention of diaphragm that originates from anterolateral surface of upper 3 lumbar vertebrae
Left crus of diaphragm
-muscular extension of diaphragm that originates from anterolateral surface of upper 2 lumbar vertebrae
Apertures of the diaphragm
-caval opening
-esophageal hiatus
-aortic hiatus
Caval opening location
-in central tendon
-at level T8
Caval opening function
-opening for inferior vena cava
Esophageal hiatus location
-in right crus
-at level T10
Esophageal hiatus function
-opening for esophagus
Aortic hiatus location
-between left and right crus
-at level T12
Aortic hiatus function
-opening for abdominal portion of aorta
Intercostal muscles
-external intercostals
-internal/innermost intercostals
External intercostals
-fibres run anteroinferiorly from the lower border of rib (put hand in pocket)
Internal/innermost intercostals
-fibres run posterosuperiorly from upper border of rib
Muscle strain
-stretching or tearing of muscle fibres, because of too much stretch or forced contraction
Movements that would cause an intercostal muscle strain
-twisting
-reaching upwards
Joints of the sternum
-manubriosternal joint
-xiphisternal joint
Manubriosternal joint
-where inferior border of manubrium articulates with superior part of sternal body (sternal angle)
What is manubriosternal joint in line with
-T4 and T5
Xiphisternal joint
-attaches the xiphoid process to sternal body
What is xiphisternal joint in line with
-T9
Parts of the intervertebral disc
-annulus fibrosus
-nucleus pulposus
Annulus fibrosus
-outer ring of fibrocartilage
Annulus fibrosus function
-to resist shear forces
Nucleus pulposus
-inner gelatinous structure
Nucleus pulposus function
-resist compressive forces
Herniated disc
-bulging of nucleus pulposus through the weak spots of annulus fibrosus
-if ruptured completely, can compress intervertebral foramen contents
Herniated disc symptoms
-localized back pain
-numbness
-weakness
Rib fracture
-results in injury to internal organs such as lungs
Rib fracture symptoms
-localized chest and back pain
Rib bruising
-bruising of skin over a rib
Rib bruising symptoms
-localized pain and swelling of the area
Rib inflammation symptoms
-chest wall pain
-may span area of more than one rib
How is a rib fracture often caused
-direct blow to the chest
What is a break in costal cartilage considered
-rib fracture
Thoracic apertures
-thoracic inlet
-thoracic outlet
Thoracic inlet
-allows passage between thorax and neck
What is the thoracic inlet formed by
-manubrium
-rib 1
-body of T1
Thoracic outlet
-allows passage between thorax and abdomen
What is the thoracic outlet formed by
-xiphoid process
-costal margin
rib 11 & 12
-body of T12
Thoracic outlet syndrome
-actually associated with thoracic inlet
-can occur when blood vessels or nerves passing through thoracic inlet are compressed
Common causes of thoracic outlet syndrome
-physical trauma
-repetitive injuries
-anatomical defects
-pregnancy
Symptoms of thoracic outlet syndrome
-pain and numbness in neck and shoulders
-due to compression of blood vessels and nerves travelling through the region
Internal thoracic arteries
-2 paired arteries located lateral to sternum
-main blood supply of anterior thoracic wall
Types of intercostal arteries
-anterior intercostal arteries
-posterior intercostal arteries
Anterior intercostal arteries
-arise from internal thoracic arteries
-pass around thoracic wall in costal groove of ribs to form anastomosis with posterior intercostal arteries
Posterior intercostal arteries
-branches off the thoracic aorta
-travels anteriorly to anastomose with anterior intercostal arteries
Subcostal arteries
-12th pair in intercostal space
-run inferior to costal margin compared to intercostal arteries
Intercostal and subcostal veins
-venous drainage pairs with anterior intercostal veins, posterior intercostal veins, and subcostal veins
-all drain deoxygenated blood into the heart
What do thoracic spinal nerves pass through
-intervertebral foramina
Parts of thoracic spinal nerves
-rami
-branches
Thoracic spinal nerves rami
-after exiting intervertebral foramen, each thoracic nerve divides into dorsal and ventral ramus
Ventral rami
-called intercostal nerves
-run in the costal grooves of corresponding ribs
Dorsal rami
-supply the deep muscles of the back segmentally and overlying skin
Thoracic spinal nerve branches
-lateral cutaneous branch
-terminal, anterior cutaneous branch
What do thoracic spinal nerve branches innervate
-skin of the thoraco-abdominal wall
Intercostal nerves 1-6
-innervate the intercostal muscles of thoracic wall and overlying skin
Intercostal nerves 7-12
-innervate abdominal muscles and overlying skin
Main innervation of diaphragm
-phrenic nerve
What are the phrenic nerves formed from
-C3, C4, C5
Phrenic nerve purpose
-provide motor innervation to diaphragm and sensory innervation to central tendon
Internal structures of the breast
-lobes
-suspensory ligament
-lactiferous ducts
Lobes of the breast
-each breast is divided into 15 to 20 lobes that contain mammary glands
Suspensory ligaments (of cooper)
-separate lobes by radial septa called suspensory ligaments
Lactiferous ducts
-produce lactiferous products
Mammary duct ectasia
-condition where lactiferous duct widens, causing duct walls to thicken and may be become blocked or clogged with product
Mammary duct ectasia symptoms
-nipple discharge
-breast tenderness
-breast lump
When might mammary gland ectasia be more prevalant
-may be more prevalant in perimenopausal women
Complications associated with breast augmentation
-pectoralis muscle rupture
Pectoralis muscle rupture symptoms
-tearing/popping
-pain
-weakness
-reduced range of movement in shoulder
Arterial supply of lateral breast
- lateral thoracic arteries
-branches of axillary artery
Arterial supply of medial breast
-branches of internal thoracic artery
Pagets disease of the breast
-rare form of breast cancer
-begins as mass at nipple and can spread through arterial/lymphatic system
Pagets disease of the breast symptoms
-shape changes
-formation of crusting of lactiferous products at nipple
Lymphatic drainage of breast lateral component
-axillary nodes
Lymphatic drainage of breast medial component
-parasternal nodes
Lymphatic drainage of the breast superior component
-supraclavicular nodes
Intraductal papilloma
-begins as a small tumor and can form in a lactiferous duct in the breast
-typically felt as a small lump confined to region proximal to nipple
Apex of the heart position
-directed forward, downward, and to the left
Base of the heart position
-posterior surface
Pericardium
-sac that encloses heart and the roots of great vessels entering and leaving it
Location of heart
-lies behind sternum and in central part of thoracic cage
Size of the heart
-clenched fist
Pericarditis
-inflammation of the pericardium
-idiopathic in most patients
What does idiopathic mean
-arises spontaneously
-no known cause
What can pericarditis cause
-build up of fluid in the body cavity such as pericardial cavity
Symptoms of pericarditis
-diaphragmatic spasms
-shortness of breath
-chest pain
Sensory innervation
-phrenic nerves
-also provide sensory innervation to fibrous pericardium and serous parietal pericardium
Referred pain in a heart attack
-one of the first signs of a heart attack
-pain in shoulder and arm
Ventricular outflow tracts
-left ventricular outflow tract
-right ventricular outflow tract
Left ventricular outflow tract
-superior wall of left ventricle consists of vestibule leading to aortic orifice
Left ventricular outflow tract aortic orifice
-where aortic valve is
-which has 3 semilunar cusps and 3 aortic sinuses
Right ventricular outflow tract
-superior wall of right ventricle is smooth and funnel shaped, forming infundibulum, which leads to pulmonary trunk carrying deoxygenated blood to lungs
Right ventricular outflow tract pulmonary orifice
-where pulmonary valve is
-which has 3 semilunar cusps
Hypertrophic cardiomyopathy
-caused from long term excessive endurance exercise
-may induce pathologic structural remodelling of heart and large arteries such as thickening of heart musculature
Hypertrophic cardiomyopathy symptoms
-shortness of breath
-chest pain during exercise
-fainting
Hypertrophic cardiomyopathy possible cause
-left ventricular outflow tract obstruction due to abnormal mitral valve opening/closing
Is hypertrophic cardiomyopathy hypertrophy symmetric or asymmetric
-asymmetric
Mitral valve prolapse
-condition in which mitral valve cusps do not close properly because of abnormally long (or short) chordae tendineae or malfunctioning papillary muscles
Mitral valve prolapse mitral valve
-causes mitral valve to flop backward into atrium, which causes regurgitation back into atrium
Mitral valve prolapse regurgitation
-can sometimes affect left ventricular outflow which would result in regurgitation between left atria and left ventricle
Mitral valve prolapse symptoms
-heart palpitations
Interventricular septum
-divides left and right ventricles to isolate oxygenated and deoxygenated blood
2 parts of the interventricular septum
-thick muscular part
-thin upper membranous part
Ventricular septal defects
-causes ventricular walls and interventricular septum to be thickened
-this is because blood pressure in the left ventricle is higher than the right
Most common site of ventricular septal defect
-membranous part
Skeleton of the heart
-dense connective tissue that is the site of attachment of the atrial and ventricular muscles
-as well as the heart valves
Calcific aortic stenosis
-progressive fibro-calcific remodelling and thickening of aortic valve leaflets that evolve over years to cause severe obstruction to cardiac outflow
What is progressive fibro-calcific remodelling
-calcification to fibrous tissue in the heart
What does calcific aortic stenosis do to aortic valve
-causes it to narrow
-causing pressure to increase in left ventricle
-left ventricle may enlarge to compensate for the blockage
Who does calcific aortic stenosis affect
-adults 65+
Calcific aortic stenosis symptoms
-shortness of breath
-chest pain
-feeling faint/dizzy when exercising
What does the aorta do
-carries oxygenated blood away from the heart
Path of the aorta
-follows a pathway arching backward and to the left of vertebral column
3 main branches of arch of aorta
-brachiocephalic
-left subclavian
-left common carotid
What does the brachiocephalic artery split into
-right common carotid
-right subclavian
How far does brachiocephalic artery travel before bifurcation
-4-5 cm
What is an aneurysm
-abnormal widening or ballooning of part of an artery due to weakness in the wall of the blood vessels
Aortic aneurysm symptoms
-chest or back pain
-difficulty breathing
-shortness of breath
Left ventricular angiography
-dye injected in a specific order to test for aortic aneurysm
Order of dye injected in left ventricular angiography
-aorta
-brachiocephalic artery
-left common carotid artery
-left subclavian artery
Right internal thoracic artery origin
-right subclavian artery
Left internal thoracic artery origin
-left subclavian artery
How many sinuses does the aorta have
-3
What do left and right aortic sinuses give rise to
-left and right coronary arteries
What does the posterior aortic sinus give rise to
-nothing
What do the left and right coronary artery supply
-the heart itself
Right and left coronary arteries anastomoses
-anastomose to form a circle in coronary sinus between atria and ventricles
-anastomose as a loop in interventricular sulcus between ventricles
Coronary artery disease
-significant occlusion in any portion of the coronary circulation will reduce blood flow to the heart
Coronary artery disease symptoms
-chest pain
-shortness of breath
-heart attack
What is a pleural recess
-potential space of pleural cavity which are not filled with lung tissue during expiration
2 pleural recesses
-costomediastinal recess
-costodiaphragmatic recess
Pleural effusion
-when pleural recesses fill with fluid
-expanding of the lungs may be impaired
Pleural effusion symptoms
-difficulty breathing
-pain extending into should/neck region
Costodiaphragmatic recess location
-between costal and diaphragmatic pleura
-below inferior part of lungs
What could pleural effusions in costodiaphragmatic recesses be caused by
-underlying heart failure
-liver cirrhois
Costomediastinal recess location
-anterior thorax
-between costal mediastinal parietal pleura
Which costomediastinal recess is larger
-left recess
Parietal pleura innervation
-intercostal nerves and phrenic nerves
Visceral pleura innervation
-autonomic innervation
What types of sensation is visceral pleura sensitive/not sensitive to
-not sensitive to pain, temp, or touch
-sensitive to stretch
Hilum of the lungs
-depression centred in medial surface of lung
-where structures enter and exit the lung
Pulmonary arterial hypertension
-high blood pressure in pulmonary arteries
-causes vessels walls to be stiff, swollen and build up plaque
-impedes blood flow to the lungs, increasing artery pressure which potentially compresses adjacent bronchi
-can also cause heart muscle strain due to greater force having to be exerted
Pulmonary arterial hypertension symptoms
-tightness in thoracic wall
-shortness of breath
-fatigue
-fainting
What does the brachiocephalic vein drain into
-superior vena cava
Azygos vein
-one of the main tributaries of superior vena cava
Azygos vein location
-enters thorax from abdomen through aortic hiatus (T12) of diaphragm
-ascends to the right of lower thoracic vertebral bodies
Tributaries of the azygos vein
-hemiazygos veins
-accessory hemiazygos veins
-right posterior intercostal veins
-right bronchial veins
Hemiazygos veins
-drains the left posterior intercostal veins
Accessory hemiazygos veins
-drains the left posterior intercostal veins
Right posterior intercostal veins
-drain directly into azygos vein
-unlike its left counterpart
Right bronchial veins
-remove deoxygenated blood from the lungs
Main ducts in lymphatic drainage of the upper body
-thoracic duct
-right lymphatic duct
Thoracic duct
-drains lymph from left side of head, neck, thorax, left upper limb and all structures below diaphragm
Right lymphatic duct
-drains lymph from the right side of the head and neck, thorax, and right limb
Sarcoidosis
-inflammatory disease that causes abnormal masses or nodules to form in pulmonary, bronchopulmonar (hilar), and paratracheal lymph nodes
Arterial supply of the lung
-descending thoracic aorta
Descending thoracic aorta
-continuation of aortic arch at level T4/T5 and provides oxygenated blood to the thorax
Anxiety with dyspnea
-constriction of broncial arteries could result in decreased blood supply to the lung tissue
Anxiety with dyspnea symptoms
-shortness of breath
-chest tightness
-hyperventilation
-fainting
-nausea
