Thoracic cage Flashcards
(27 cards)
Ribs
true ribs 1-7
False ribs
8-12
floating
11-12
coastal cartilage
connect sternum to ribs
provide elasticity within the walls of the thorax allowing the chest to expand
typical rib
head- wedge shaped, 2 articular facet for articulation of corresponding vertebrae and vertebrae below
crest
neck- connects head to body with roughned tubercle with a facet for the articulation with the transverse process of the corresponding vertebrae
shaft-flat and curved with a groove for the neurovascular supply of the thorax, protecting the vessels and nerves from damage
atypical 1st rib
flat, slopes inferiorly attaches to the manubrium
contain the scalene tubercle and 2 separate grooves
atypical 2nd rib
like 1st rib but twice aslong
atypical 10th ribs
only one facet for articulation with corresponding vertebrae
atypical 11-12th rib
no neck, only one facet for articulation with corresponding vertebrae
intercostal space
space between ribs
content-
intercostal arteries and veins
intercostal nerve
external,internal and innermost intercostal muscles
spinal nerves
spinal canal very narrow in thoracic spine
spinal cord injuries with spinal fractures in this region
thoracic spinal nerve runs in intercostal space between ribs
sternum
manbrium
body
xiphoid process
attachment of ribs
orientation
thoracic facet joints are orientated in the plane which facilitates rotation but limits side flexion
movement of thoracic spine
thoracic spine relatively less mobile than cervical or lumbar
rotation at greatest at thoracic spine
flexion and lateral flexion more resticted
movement of the thoracic cage
inspiration
increasing A-P diameter as 1st-7th rib elevate carrying sternum upwards and forwards
increase in transverse diameter 6th-10th ribs elevate, the shaft moving upwards and outwards
increasing in vertical diameter as diaphragm descends
pump handle
action of the upper ribs
superior and anterior movement of the sternum
bucket handle
action of the lower ribs
elevation of lateral shaft of the rib
inspiration
diaphragm contracts
moves down
ribcage expands as accessory muscles of respiration contract
air is inhaled
expiration
diaphragm relaxes
moves up
ribcage expands gets smalller accessory muscles of respiration relax
msucles of the rib cage
increase thoracic dimensions during inspiration
support the thoracic cage
intercostal muscles prevent aby recession or bulging of intercostal spaces
inhibit the lungs natural tendency to collapse
the diaphragm
lumbar parts
coastol part
sternal part
central tendon
surface area 900cm3
innervated by the phrenic nerve C3C4C5
reduce in length by 40%
lots of functional resevre
muscles of respiration
Sternocleidomastoid Scaleni Serratus Anterior Pectoralis Major Quadratus Lumborum
Abdominal muscles
Latissimus Dorsi
inspiration
Diaphragm
external intercostal
Quadratus lumborum (deep inspiration)
expiration (forces)
Intercostal muscles
transverse thoracis
subcostals
serratus posterior inferior
external obliques internal obliques rectus andomininus transverse abdominus latissimus dorsi
