rib cage and ventilation Flashcards
label joints and ligaments
rib joints
what is the axis of rotation for the upper ribs (1-6). what motion are the ribs biased towards?
coronal axis - motion is biased toward sagittal plane
think pump handle
rib joints
what is the axis of rotation for the lower ribs (7-10)? what direction is motion biased towards?
A-P axis - motion is biased towards frontal plane
think bucket handle
joints - costovertebral joints
the ribs has a ________ rotation along axis of rotation through costovertebral joints
at lower ribs
posterior
joints - costovertebreal joints
sight thoracic extension can be obsered during what type of respiration?
at lower ribs
forced inspiraton
joints- costovertebral
what does cartilage store at sternocostal joints?
at lower ribs
energy!
potential energy waiting to be converted into kinetic energy
joints -costovertebral
angulation of upper ribs creates slightly more elevation in what direction?
at upper ribs
anterior
the rib cage acts in a closed kinetic chain motion - exception is which ribs?
11 and 12 - have an OKC movement
*these ribs are not storing potential energy
joints - thoracic spine
ribs 11 and 12 operate in what type of motion?
caliper motion
- lateral (inhalation)
- medial (exhalation)
muscles
quiet expiration is a passive mechanism and volume change is due to?
elastic recoil of muscles
muscles
what muscles are involved in quiet expiraton?
none - passive mechanism
muscles
what muscles are involved in forced expiration?
abdominal muscles (primary)
- rectus abdominis
- obliquus externus abdominis
- olbiquus internus abdominis
- transversus abdominis (pulls ribs down and together)
transversus thoracic
internal intercostals
muscles
what costal muscles is involved in forced expiration?
internal interocstals - interosseous fibers
internal for expration!!
muscles
what muscles are involved in quiet inspration?
diaphragm (primary)
scalenes (from superior aspect ribs 1-2)
intercostals
- external intercostals : major role
- internal intercostals- parasternal fibers: lesser role
muscles
what muscles are invovled in forced inspiration?
accessory muscles
- serratus posterior S & I
- levator costarum
- SCM
- latissimus dorsi
- erector spinae
- pec major and minor
- quadratus lumborm
*abdominals muscles indirectly assist
muscles
how does the latissimus dorsi aide in respiration?
if arms dont move - they will pull at thoracolumar fascia, moving into extension creating space between ribs for breathing
muscles
how do the pec major and minor play a role in forced inspiration?
pull ribs superolateral
muscles
how does the QL play a role in forced inspiration?
bilaterally: extension at lumbar
unilaterally: pull on 12th rib inferiorly
what is boyles law?
pulling up increases the voume and decreases the pressure
pushing down decreases the volume and increases the pressure
what are the steps of inspration inregard to boyles law
- increased intrathoracic volume due to muscle contraction
- pressure in interpleural space (already negative) is further reduced causing lung expansion
- lung expansion then reduces alveolar pressure below atmospheric pressure
(wants to find quialibrium so draws air in )
what are the steps of expiration in regards to boyles law
- muscles relax after inspiration
- intrathoracic volume decreases by elastic recoil of muscles
- forces expiration requires muscle contraction of expiratory muscles
ventilation- defintions
total lung capacity
its a #
5.5-6 L
ventilation- defintions
vital capacity
max amount of air exhaled after max inspiration
ventilation- defintions
tidal volume
amount of air moved during each breathing cycle (at rest 0.5 L)
ventilation- defintions
inspiratory reserve volume
amount of air that can be inspired after an inhalation at rest *beyond tidal volume
ventilation- defintions
expiratory reserve volume
amount of air that can be exhaled after an exhalation at rest (tidal vol increases, ERV decreases)
ventilation- defintions
residual volume
airthat just sits in lungs - not usable air
*think about raisin lung anology
activity :P
Draw lung volume/time ventilation chart
clinical considerations
chronic obstructive pulmonary disease (COPD)
decreased elastic recoil of lungs = decreased airflow of lungs
*primarily inability to exhale sufficiently
clinical considerations
what remains in lungs with COPD?
air after exhalation (hyperinflation of the lungs)
clincial considerations
what anatomical consideration is noted in those with COPD?
barrel chest (A/P direction)
what clnical considerations should be noted that decrease inspiratory reserve?
posture, scoliosis, hyper kyphosis,
sitting position
clinical considerations
pectus carinatum
sternum sticks out - decreased ventilation
clinical considerations
pectus excavatum
hollowed (concaved) sternum - decreased ventilation
What effect does COPD have on the biomechanics of the thorax and the inspiratory muscles
Within the lungs, the increased air does not allow the diaphragm to return to its usual high domed shape and location so that there is a flattening of the diaphragm at rest. The fibers of the diaphragm remain shortened even after exhalation, decreasing the available range of contraction. The angle of pull of the flattened diaphragm fibers becomes more horizontal with a decreased zone of apposition. In severe cases of hyperinflation, the fibers of the diaphragm are aligned more horizontally than vertically. Contraction of this very flattened diaphragm will pull the lower rib cage inward, actually working against lung inflation. SCM is put into a shortened position making them much less efficient.
