Thoracic Wall Flashcards
What is the thorax
The part of the body between the neck and the abdomen
what does the thorax include?
includes the cavity enclosed by the ribs, sternum, and dorsal vertebrae & contains the chief organs of circulation and respiration; the chest.
Mediastinum
central compartment
Shape of the thoracic skeleton
- shape of a dome, birdcage or a truncated cone
- narrowest superiorly with circumference increasing inferiorly
- relatively thin-walled
what is convex superiorly?
floor in the respiratory diaphragm
Normal adult chest
no structural deformities or visible retraction
barrel chest
increased anteroposterior diameter
functions of the thorax (4)
- Protect vital thoracic/abdominal organs from external forces.
- Resist the negative internal pressure created by the elastic recoil of the lungs.
- Provide attachments for and support the weight of the upper limbs.
- Provide the origin for some upper limb muscles and attachments for muscles of the abdomen, neck, back & respiration.
3 types of ribs
- True
- False
- Floating
True ribs
1-7 attach vertebrae to sternum
False ribs
8-10 have cartilages attached to the cartilages of ribs superior (not attached to sternum)
Floating ribs
11-12 have cartilages ending in the posterior abdominal wall musculature
what do cartilages 7-10 form?
infrasternal angle
how are ribs and costal cartilage separated?
intercostal space
Superior thoracic aperture
(= thoracic outlet or inlet)
bounded by 1st thoracic vertebra, 1st pair of ribs, and superior border of manubrium
Inferior thoracic aperture
closed by diaphragm, structures must pass through the diaphragm or behind it
Rib osteology
- head
- neck
- tubercle
- angle
- costal groove (intercostal vessels)
- body or shaft
- sternal end
What does articular facets of head articulate with?
with inferior and superior costal facets of adjacent thoracic vertebrae
what does articular facet of tubercle articulate with?
with costal facets of transverse process of vertebrae of same #
Costal groove is known as what?
intercostal vessels; runs along the inferior line of the rib
supernumerary ribs
of ribs is increased by the presnece of cervical and/ or lumbar ribs, or decreased by the failure of the 12th to form
cervical ribs
relatively common and may interfere with neurovascular structures exiting the superior thoracic aperture
thoracic outlet syndrome
group of disorders that occur when there is a compression, injury, or irritation of the brachial plexus and/ or subclavian vessels in the lower neck and upper chest
What are the 3 parts that make up the sternum?
- manubrium
- body
- xiphoid process
what are the 3 areas of the manubrium?
- Jugular notch
- Clavicular notch
- notch for 1st costal cartilage
body
notches for costal cartilages
what 2 things can become a synostosis
fusion of manubriosternal and xiphisternal joints
sternal cleft =(sternal foramen)
failure of fusion between halves of the sternal bars
cardiac tamponade
=pericardial tamponade
- type of pericardial effusion where fluid, pus, blood, clots, or gas accumulates in the pericardium
- results: slow or rapid compression of heart
Chest wall deformities
- Pectus carinatum
- pectus excavatum
- sternal cleft
- cleft sternum
- poland syndrome
- rare lesions (ectopia cordis)
pectus carinatum
- abnormal development causing sternum to protrude
- seen at birth or adolescent males
- may occurs as a solitary congenital abnormality or in association with other genetic disorders or syndromes
pectus excavatum
- ” funnel chest”
- abnormal development of rib cage in which the sternum grows inward
- cause is unknown
sternal cleft
- sternum come together but do NOT fuse
- treatment: magnet correction where a magnet is placed on the sternum and on a shift to help reposition the sternum
poland syndrome
deformability of chest wall pectoralis muscle
Ectopia cordis
= rare lesions
- heart is out of the thorax
Congenital scoliosis
Caused by a bone abnormality present at birth.
Neuromuscular scoliosis
A result of abnormal muscles or nerves. Frequently seen in people with spina bifida or cerebral palsy or in those with various conditions that are accompanied by, or result in, paralysis.
Degenerative scoliosis
may result from traumatic bone collapse, previous major back surgery, or osteoporosis.
Idiopathic scoliosis
most common type of scoliosis, idiopathic scoliosis, has no specific identifiable cause. There are many theories, but none have been found to be conclusive. There is, however, strong evidence that idiopathic scoliosis is inherited.
types of joints
- costotransverse
- costochondral
- interchondral
- sternocostal
costotransverse joints
▪Upper ribs (1-7) rotate
▪Lower ribs (8-10) glide
▪Ribs 11 and 12 do not articulate with transverse processes.
costochondral joints
▪Primary cartilaginous joints and no movement.
interchondral joints
▪Some plane synovial joints (b/t costal cartilages 6-9).
▪Some fibrous (b/t cartilages 9& 10).
sternocostal joints
- 1st joint is cartilaginous
- joints 2-7 are synovial plant joint
intercostal muscles
- function during respiration
- occupy intercostal spaces
what do intercostal muscles include?
- external
- internal
- innermost
- subcostal
- transversus thoracis
external intercostal
- attach superiorly to the inferior border of the rib above and inferiorly to the superior border of the rib below.
- Fibers run infero-anteriorly.
- Function to elevate ribs during forced inspiration.
Internal & Innermost intercostals
▪Attach superiorly to the inferior border of the rib above and inferiorly to the superior rib below. Fibers run inferoposteriorly.
▪functions to depress the ribs during forced respiration.
what separates Internal & Innermost intercostals
intercostal neurovascular bundle
subcostalis
▪Attach superiorly to internal surfaces of lower ribs near their angles and inferiorly to superior borders of ribs 2 or 3 levels below.
▪Fibers run in same orientation and blending with internal and innermost intercostals.
▪ same function as internal intercostals.
Transversus thoracis
▪Attaches superiorly on the posterior sternum and inferiorly on costal cartilages 2-6.
▪Functions to depress ribs
levator costae
▪O: Transverse processes
▪I: Rib below between tubercle and angle.
▪A: Elevate ribs
Serratus posterior superior
▪O: Spines of C7-T3
▪I: Ribs 2-4
▪A: Elevate ribs
Serratus posterior inferior
▪O: Spines of T11-L2
▪I: Ribs 8-12
▪A: Depress ribs
What forms the intercostal nerves
ventral rami
roots function
carry sensory (dorsal) OR motor (ventral)
rami function
mixed nerves and carry both sensory and motor
dermatome
area of skin supplied by nerve from a single spinal root
sensory impairment effect dermatome?
sensory impairment for a specific dermatome is related to level of spinal cord injury
T1
medial arm
T4
Nipple line
T10
Navel
Thoracotmy
surgical opening through the thoracic wall to access the lungs, heart, esophagus, diaphragm, and the thoracic aorta.
Thoracentesis
a procedure to remove fluid from the space b/t the lining of the outside of the lungs (pleura) and the wall of the chest.
Nerve root block
used to diagnose the specific source of nerve root pain and for therapeutic relief of low back pain and/or leg pain.
Thoracic epidural steroid injections
most commonly used to reduce the pain associated with herpes zoster (shingles).
Bucket handle movement
lateral-most parts of the ribs are elevated and the transverse diameter of the thorax increases
thorax pump handle movement
The ribs are also elevated at the neck (especially ribs 2-6) resulting in an increase in the antero-posterior diameter
inhalation
- active, muscles contract
- chest wall & lungs expand
- expansion of ribs move sternum upward and outward
exhalation
- passive, muscles relax
- chest cavity & lungs contract
- ribs and sternum depress
vasculature of the thoracic wall
- parietal (somatic) branches of the thoracic aorta
- visceral branches of thoracic aorta
what are the primary blood supplies to the thoracic wall derived from?
branches of the aorta and subclavian arteries
internal thoracic artery
descends into thorax 1.2cm lateral to edge of sternum, and ends at 6th costal cartilage by dividing musculophrenic and superior epigastric arteries
internal thoracic vessels
Give off anterior intercostal arteries to the first six intercostal spaces
anterior intercostal arteries ____ with posterior intercostal arteries in the intercostal space
anastomose
Posterior Intercostal Arteries
▪Two of these arteries branch off the superior intercostal artery in the first two intercostal spaces
▪The remaining posterior intercostal arteries are branches of the descending thoracic aorta
Posterior Intercostal Vveins
▪Most of these veins return blood to the azygos and hemiazygosveins.
▪Left superior intercostal is the exception
Spatial relationships in intercostal space
innermost intercostal muscle consist of vein, artery, nerve.. it lines in between the external and internal layers reflected
