trunk musculature - exam 1

Question 1

what everyday position has a higher load on the NP in the lumbar spine?

Answer 1

bending over (at lumbar spine) to lift a heavy object
-in general, holding/moving a heavy object increases load on the NP in the lumbar spine

Question 2

list these seated positions in order from highest pressure to NP –> lowest pressure to NP
- slumped
- leaning back
- straight sitting

Answer 2

highest:
- slumped
- straight sitting
- leaning back
lowest:

Question 3

what everyday position has the least amount of load to the NP in lumbar spine?

Answer 3

laying supine

Question 4

what happens to the lumbar multifidus following a low back injury?

Answer 4

experiences a number of morphological and neurophysiological changes
– one being a segmental atrophy which develops at the level of pathology, on the symptomatic side and as quickly as 24 hours after the injury

Question 5

what has happened if a disc has bulged/protruded?

Answer 5

nucleus migrates but remains contained in annulus
protrudes beyond posterior rim of vertebral body

Question 6

what is a disc herniation?

Answer 6

nucleus has herniated through the annulus fibrosis and PLL

Question 7

what is extrusion?

Answer 7

nucleus migrates thru the outer annulus
extrude through epidural space

Question 8

what is free sequestration?

Answer 8

nucleus migrates and breaks away from annulus
lodged or break off

Question 9

what is the greatest injury risk during sit ups? how would this happen?

Answer 9

if hip flexion occurs without the trunk curl
this may happen because of lack of abdominal strength, hip flexor dominance or an inability to flex the lumbar spine

Question 10

what does hip flexor contraction without a trunk curl cause?

Answer 10

dangerous anterior shear forces from hyperextension of the lumbar spine
because the hip flexors are attached to the front of the lumbar spine, the sit up phase will cause the torso to lift, pulling on the unstable extended spine

Question 11

what is occurring during the trunk flexion phase of the full sit up?

Answer 11

internal obliques and rectus abdominis are most active muscles.
as trunk is pulled towards pelvis, posterior tilt happens

Question 12

what is occurring during the hip flexion phase of the full sit up?

Answer 12

continued activation of abdominals but hip flexors are activated and are prime movers through the completion of the movement

Question 13

true or false. the axes of rotation during the full sit up shifts from the abdominals to the pelvis when going from the trunk flexion phase to hip flexion phase

Answer 13

true

Question 14

why would a full sit up be advised against?

Answer 14

causes more pressure in the discs and more spine flexion

Question 15

if you are doing full sit ups and have weak abs, what happens instead?

Answer 15

hip flexors dominate and cause early hip flexion. this puts you at a shear risk

Question 16

when doing a diagonal sit up, what is happening?

Answer 16

incorporates trunk flexion and axial rotation
right EO acts synergistically with left IO muscle
bilateral activation of rectus abdominis and transversus abdominis

Question 17

during a standard sit up, are lateral flexion torques active?

Answer 17

no they are neutralized

Question 18

when a patient lifts their arms, what muscle was contracted before or shortly after the deltoid muscle?

Answer 18

transversus abdominis.
- was not influenced by movement direction, which supports that this muscle helps with spinal stiffness

Question 19

a patient moves their arms and body but has LBP. what happened to the TA?

Answer 19

contraction was significantly delayed with all movements

Question 20

local muscles:
– location and length?
– controls:
– ____ density muscle spindles
– varying angles act as ______
–

Answer 20

– deep and short
– precise alignment and stiffness
– high
– guidewires

Question 21

global or extrinsic muscles:
– location and length?
– _____ generators
– provides?

Answer 21

– superficial and long
– torque
– strong links between regions

Question 22

what is a diastasis recti?

Answer 22

when the rectus abdominis separates along the linea alba
– looks like an indent along the linea alba

Question 23

what are the muscles of the posterior trunk?

Answer 23

3 layers:
superficial:
– trap, lats, rhomboids, levator scap, SA

intermediate:
– serratus posterior superior, serratus posterior inferior

deep:
– erector spinae group (spinalis, longissimus, iliocostalis)
– transversospinal group (semispinalis, multifidi, rotators)
short segments group (interspinalis, intertransversarius)

Question 24

what does the erector spinae group generally do? location?

Answer 24

gross movements
large ext torque

common tendon at sacrum
deep to thoracolumbar fascia
one hand width from SPs

Question 25

what does the transversospinal group generally do? location?

Answer 25

contralateral rotation & SB
bilateral contraction for extension

medial fibers
TP of one vertebra to SP of more superiorly located vertebra

Question 26

multifidi:
– runs:
– TP to SP ___
– thickest in which region?
– fills space where?
– ____ cross sectional area
– what happens with injury/pain?
– what surrounds them?

Answer 26

– post. sacrum to C2
– TP to SP 1 or 2-4 vertebrae above
– thickest and most developed in lumbar region, 2/3 muscular stabilizing capacity
– fill the space between TP/SP
– large cross sectional area
– atrophy quickly
– TA and thoracolumbar fascia surrounds them

Question 27

what does the short segments group do in general? characteristics?

Answer 27

interspinalis: extension
intertransversarius: SB
rich in muscle spindles - sensory feedback

short length
crosses only 1 intervertebral junction
most developed in cervical region
bilateral and blends with interspinous ligament

Question 28

what are the muscles of the anterior-lateral trunk?

Answer 28

rectus abdominis (strap like)
obliquus externus abdominis (wide/flat)
obliquus internus abdominis (wide/flat)
transversus abdominis (wide/flat)

Question 29

what does the anterior-lateral trunk muscle group do?

Answer 29

support and protect viscera
increase intrathoracic and intra-abdominal pressure

Question 30

what forms the linea alba?

Answer 30

anterior and posterior rectus sheaths

Question 31

rectus abdominis:
– longest _____, smallest _______
– intersected by
– runs?

Answer 31

– fascicle length, cross sectional area
– 3 transverse fibrous bands, tendinous insertions
– xiphoid –> 5-7 cartilaginous portion ribs –> crest of pubis

Question 32

external oblique:
– most ______ of lateral muscles
– fibers run:

Answer 32

– superficial
– inferior and medial (hands in pockets)

Question 33

internal oblique:
– _____ to EO
– _____ cross sectional area of abs
– fibers run:

Answer 33

– deep
– largest
– superior and medial

Question 34

what are the actions of the rectus abdominis?

Answer 34

flexes thorax and upper lumbar spine
posterior pelvic tilt

Question 35

what are the actions of the EO?

Answer 35

SB
contralateral rotator
bilateral flexor of trunk
posterior tilt of pelvis

Question 36

what are the actions of the IO?

Answer 36

ipsilateral rotator (synergist with opposite EO via linea alba)
SB
bilateral flexion of trunk
posterior pelvic tilt
increases tension in TL fascia

Question 37

transversus abdominis:
– deep or superficial?
– attachments?

Answer 37

–deepest
– ribs - iliac crest - inguinal ligament - TL fascia

Question 38

what are the actions of the transversus abdominis?

Answer 38

stabilization for other abdominal muscles
increases tension TL fascia
compression of abdominal cavity

Question 39

Quadratus lumborum:
– located?
– attaches to?

Answer 39

– posterior abdominal wall
– IC and iliolumbar ligament

Question 40

what are the actions of the quadratus lumborum?

Answer 40

bilateral: extension, vertical stabilization
unilateral: SB
“hip hiker”

Question 41

what two muscles make up the iliopsoas and their locations?

Answer 41

iliacus (fossa and lateral sacrum)
psoas (TPs T12-L5 and discs)

Question 42

what are the actions of the iliopsoas?

Answer 42

hip flexor
anterior tilt
lumbar extension
SB of trunk

Question 43

what is an example of relative degree of stabilization?

Answer 43

erector spinae T/S ext or anterior pelvic tilt

flexion –> sacrum stable
pelvic tilt –> lumbar stable

Question 44

the dorsal ramus forms nerves that innervate where?

Answer 44

innervates muscles, joints, skin of posterior trunk and neck

Question 45

the ventral ramus forms nerves that innervate where?

Answer 45

muscle, joints, skin of anterior/lateral trunk, neck and extremities

Question 46

ventral ramus:
– becomes:
– 4 major plexi are:
– innervation:

Answer 46

– an individual nerve or plexus
– C1-4, C5-T1, T12-L4, L4-S4 (most innervate limbs)
– individual intercostal and recurrent meningeal

Question 47

dorsal ramus:
– branches from:
– innervates:

Answer 47

– every spinal nerve root
– innervating structures in post. trunk (except C1-2) and dermatome across most of posterior trunk. ligaments post. side of vertebrae, capsule of facets, dorsal ligaments of SIJ