16 - MSK Body Wall & Back

Question 1

What are the two compartments of the body wall

Answer 1

dorsal (proterior) extensor
ventral (anterior) flexor

Question 2

what defines the anterior and posterior compartments

Answer 2

transverse process
- back = dorsal
- front = ventral

Question 3

what do the left and right dorsal extensors do

Answer 3

cause extension of the spine

Question 4

What is the flexor compartment innervated by

Answer 4

ventral ramus

Question 5

what is the extensor compartment innervated by

Answer 5

dorsal ramus

Question 6

what do mixed spinal nerves consist of

Answer 6

motor and sensory axons

Question 7

Describe the pathway of the ventral ramus

Answer 7

goes back –> front
gives off muscular branches (deep) –> superficial and give off sensory nerves(sensations to the skin)
Skin defined by dermatome

Question 8

Describe the pathway of the dorsal ramus

Answer 8

front –> back
deep in muscles –> superficial to skin on posterior body wall

Question 9

Which regions are capable of flexion and extension

Answer 9

cervical and lumbar regions

Question 10

What is lateral deviation

Answer 10

using muscles on the same side of front and back
(joints in vertebral column)

Question 11

What are the three muscles of the anterior body wall

Answer 11

superficial to deep

external obliques –> internal obliques –> transverse abdominus

Create broad tendon sheath

Question 12

What is the tendon sheath

Answer 12

formed by the muscles of the anterior body wall
rescuts abdominus underneath the tendon sheath (enveloped in tendon sheath)
- have tendinous insertions between muscle group

Question 13

What do the anterior body wall muscles do

Answer 13

flexing the lumbar vertebrae
increase intrabdominal pressure to aid in: micturition (urination), parturition (uterus growing –> l&b), defecation (sigmoid…)

Question 14

What are the muscles in the extrinsic muscles of the back

Answer 14

superficial
- trapezius
- rhomboids (deep to trapezius)
- Latissimus dorsi (widest muscle of the back)

origin in the axial skeleton and insertion in the appendicular skeleton
- give aciton on the appendicular skeleton

Question 15

What are the intrinsic back muscles

Answer 15

deep
attached to vertebral columns, transverse processes and their extensions and the ribs
have action on vertebral column (spine) - rotation, extnesion
innervated segmentally by dorsal ramus (b/c true back muscles)

Question 16

What are the extrinsic muscles of the back innervated by

Answer 16

ventral raumus (latissimus and rhomboids) –> peripheral nerves that rise off of brachial plexus early on before it gets out to the limb
CN XI (trapezius)

Question 17

What are the two major systems of intrinsic back muscles

Answer 17

spinotransverse system (big muscles for extension of spine = erector spinae group)
- long muscles
- stay up straight
- stabalize

transversospinal system
- short, dont go very far
- obliquely oriented
- twisting in the vertebrae

Question 18

How are the intrinsic back muscles innervated

Answer 18

segmentally by the dorsal ramus
at different levels (cervical, thoracic, lumbar

Question 19

What are the curvatures of the spine

Answer 19

4 major curvatures
- 2 kyphotic (hump) thoracic and sacrum
- 2 lordotic (backwards) cervical and lumbar

Question 20

What are abnormalities of curvatures of the spine

Answer 20

exaggeration of a normal curve
scoliosis - most common, congenital, muscle paralysis, short leg, lateral deviation
kyphosis - humpback, osteoporosis (poor posture)
lordosis - pregnancy, obesity (natural adaptation)

Question 21

what are the parts of a typical (thoracic) vertebrae

Answer 21

body (spongey bone, where most of body’s red bone marrow - where most of RBC are made)
pedicles
lamina (root - plate of spinal canal)
transverse processes
spinous process
superior articular process
inferior articular process

Question 22

What are fibrous joints
What is the function in the vertebrae

Answer 22

joins adjacent bodies of vertebrae and contain interbetertebral discs
least amount of movement but most stable

Question 23

What structure faciliatates shock absorption in the vertebrae

Answer 23

intervertebral disc
- thick collagen on outside (fibrous ring)
- inside very gelatinous (hydrated - gel cushions)
as you go through the day, water gets squished out of the vertebral column

Question 24

What are synovial joints
What is the function in the vertebrae

Answer 24

joins adjacent pedicles of vertebrae
some range of mobility (flexion and extension

Question 25

where do the mixed spinal nerves exit the vertebral column

Answer 25

intervertebral foramina

Question 26

What is formed once mixed spinal nerves exit the intervertebral foramina

Answer 26

forms a ventral ramus (thicker than dorsal cause more muscles at the front) and dorsal ramus

Question 27

What are the anterior longitudinal ligaments

Answer 27

help to keep the intervertebral discs in place very thick largely composed of collagen fibers (resist tearing and stretching)

Question 28

What are posterior longitudinal ligaments

Answer 28

help to keep the intervertebral discs in place very thin runs entire length of vertebral column

Question 29

What is the ligamentum flavum

Answer 29

composed of elastin yellow (flavum = yellow) - contains elastic tissue - can stretch and will recoil back to original position when flex vertebrae, opens spaces in back between the ligament extension- goes back to original shape wears out with age --> touch pressure proprioception when impacting spinal cord exists between the laminu, does not voer the lamin

Question 30

What are the ligaments in the vertebrae

Answer 30

anterior and posterior longitudinal ligament ligamentum flavum interspinous ligament supraspinous

Question 31

What is the interspinous ligament

Answer 31

attatchment site for back muscles (transversospinal) between the spine

Question 32

What is the supraspinous ligament

Answer 32

most superficial above/upon the spinous connects spinous processes of vertebrae really thick in cervical region

Question 33

What is the sacroiliac joint

Answer 33

sacrum articulates with the ilium of the pelvic bones = synovial joints stabalize the joint, represent thickening some rotation cocyx wants to stick out the back

Question 34

What ligaments stabalize the sacroiliac joints

Answer 34

sacrospinous and sacrotuberous ligaments prevent the rotation of the sacrum

Question 35

What are the causes of lower back pain

Answer 35

mechanical: ligament sprain or muscle strain neurogenic: compression of spinal nerves

Question 36

What is mechanical pain

Answer 36

ligament sprain or muscle strain well localized bilateral (usually on the midline, hard to determine which side)

Question 37

What is neurogenic pain

Answer 37

compression of spinal nerves pain radiates often unilateral

Question 38

What is neurogenic pain caused by

Answer 38

narrowing intervertebral foamina (spinal stenosis) disc degeneration (usually when older) - interverebral disc in compressed --> causes intervertebral space to become smaller --> compresses nerves --> generates pain signals and eventually stops facet joint arthritis disk herniation: common between vertebrae l4& l5 and vertebrae l5 and l1 - results in entrapment of l5 or s1 spinal nerve respectively - s1 spinal nerve entrapment is most common

Question 39

What is the straight leg test

Answer 39

for isolating spinal nerves involved places traction on the roots of the lumbosacral plexus ROM 30 = L4 ROM 90 = L5 no pain at 90 = mechanical back pain ROM 0 = L2-L3`

Question 40

Which regions have the greates ROM

Answer 40

cervical and lumbar region

Question 41

Why are the 4 muscles arranged aroudn the joint axis

Answer 41

flexion extension lateral deviation (felxion) circumduction

Question 42

What does the sternocleidomastoid

Answer 42

flexion of cervical vertebrae innervated by CN XI

Question 43

What is the upper fibres of trapezius

Answer 43

extend cervicle vertebrae innervated by CN XI

Question 44

What are the muscles that move the lumbar spine

Answer 44

abdominal muscles (flexion) Spinotransverssystem (no hold back) intervatted segmentally by dorsal ramaus transversospinal system (rotain)