CSD 378 LCQ exam #2 Questions and
Answers with Verified Solutions | Latest
Updated 2026
sternocleidomastoid
elevate sternum and clavicle
to lift upper ribs
scalenes
elevate ribs 1 and 2 when head
is stable
pectoralis major
elevate sternum and ribs if arm
is stable; increase transverse
dimension of rib cage
pectoralis minor
elevates shoulder; if shoulder
is fixed it elevates ribs 3-5
subclavius
fixing clavicle allows this to
elevate rib 1
serratus anterior
if scapula is fixated, elevates
lower 9 ribs
, trapezius
stabilize shoulders and
indirectly rib cage, shrug
shoulders, affects head
movement
diaphragm
flattens, drive central tendon
inferiorly, inhalation
intercostals (external and
internal interchondral)
raise ribs
levator costarum
slight elevation of posterior rib
cage
serratus posterior superior
elevate ribs 2-5
transversas thoracis
lowering of costal cartilages 2-
6
serratus posterior inferior
rib lowering for expiration
internal intercostal interosseus
depress and lower ribs 1-11
Answers with Verified Solutions | Latest
Updated 2026
sternocleidomastoid
elevate sternum and clavicle
to lift upper ribs
scalenes
elevate ribs 1 and 2 when head
is stable
pectoralis major
elevate sternum and ribs if arm
is stable; increase transverse
dimension of rib cage
pectoralis minor
elevates shoulder; if shoulder
is fixed it elevates ribs 3-5
subclavius
fixing clavicle allows this to
elevate rib 1
serratus anterior
if scapula is fixated, elevates
lower 9 ribs
, trapezius
stabilize shoulders and
indirectly rib cage, shrug
shoulders, affects head
movement
diaphragm
flattens, drive central tendon
inferiorly, inhalation
intercostals (external and
internal interchondral)
raise ribs
levator costarum
slight elevation of posterior rib
cage
serratus posterior superior
elevate ribs 2-5
transversas thoracis
lowering of costal cartilages 2-
6
serratus posterior inferior
rib lowering for expiration
internal intercostal interosseus
depress and lower ribs 1-11