BACK, SPINE Flashcards
What do the skin dimple on the lower back rep?
PSIS
posterior superior iliac spine
THe role of the extrinsic back muscles?
MOVES UPPER limb
What is the role of the intrinsic back muscle?
- maintains back posture
- moves spine
- supports the spine
Why is it referred to as “intrinsic” back muscles?
- it’s entirely within the BACK
Name the extrinsic back muscles.
- rhomboids
- Latissimus Dorsi
- Trapezius
- Levator Scapulae
Name the 2 gr.s of intrinsic back muscles.
- erector spinae
2. transversospinalis (deep)
How many muscle grs. a.w the erector spinae?
3 vertical muscle groups LATERAL to the spine
Where are the erector spinae muscle groups attached, inferiorly and superiorly?
INFERIORLY: COMMON tendon attaches to the SACRUM and the ILIAC crest
- superiorly: individual muscle fibres attach (via tendon) to: a rib/ transverse process/ spinous process
Where is the transversospinalis muscle located?
- within the GROOVES between the TRANSVERSE and SPINOUS processes
Where does the transversospinalis muscle attach to ?
Between the:
- skull and vertebra
- rib and vertebra
- one vertebra to another
- the SACRUM and the vertebra
What is the nerve supply for each intrinsic back muscles?
- segmental nerve supply (dermatome/ myotome pattern
- POSTERIOR RAMI branches (cervical/ thoracic/ lumbar)
Name the muscles of the posterior abdominal wall.
- psoas major
- Quadratus Lumborum
(seen antero-lateral to the vertebra)
Muscles of the anterior abdominal wall?
- transversus abdominis
- internal oblique
- external oblique
What occurs with the intrinsic muscle on lateral flexion?
- unilateral contraction of erector spinae
Why do the vertebra increase in size as you descend the spine, until the sacrum?
- because each vertebra would have to bear more weight, as you go lower down the spine
- —-the vertebrae become smaller once wgt has been transferred to the HIP bones
How many adult vertebrae in total?
What is the distribution like?
33 in total
- 7 cervical
- 12 thoracic
- 5 lumbar
- 5 Sacral (fuses to form 1 sacrum)
- 4 coccygeal (fuses to form 1 coccyx)
List the normal curvatures of the spine.
- cevical LORDOSIS
- Thoracic Kyphosis
- Lumbar Lordosis
- Sacral kyphosis
What part of the vertbra enables mobility with the adjacent vertebra?
- the inferior articular process and the superior articular processes
(via synovial joints)
What protects the spinal cord?
the vertebra
—the vertebral arch (2 laminae and 2 pedicles)
Where do spinal nerves ARISE from?
from the intervertebral foramen (formed BETWEEN adjacent vertebrae)
Which part of the vertebrae may be affected by arthritis?
- facet joint between articular processes of adjacent vertebrae
Where are intervertebral discs NOT found?
- none between C1-C2
- none between sacrum and coccyx
What is the importance of the intervertebral discs?
- important for WGT-bearing and strength
Discuss what makes up the intervertebral discs.
- outer fibrous ring= ANNULUS FIBROSUS : for strong bond
- inner soft pulp= NUCLEUS PULPOSUS (for flexibility and protection)
Can the intervertebral discs move much?
- each disc moves a SMALL amount; the summation produces a LARGER movement
Name the 3 major ligaments of the spine.
- ligamentum flavum
- Posterior longitudinal ligament
- Anterior Longitudinal ligament
- Supraspinous Ligaments
- Interspinous Ligament
Describe the attachments of ligamentum flavum.
- short
- connects adjacent laminae posterior to spinal cord
What are the attachments of the posterior longitudinal ligament?
- narrow, weak
- less support for disc
- —-PREVENTS OVERFLEXION of the spine
Describe the attachments of the anterior longitudinal lig.
- BROAD, strong
- stronger support for DISC
- prevents over-EXTENSION of the spine
What are the supraspinous ligaments attachments like?
- connects tips of the spinous processes together
strong and fibrous
What are the interspinous ligament attachments like?
- —runs along the superior and INFERIOR surfaces of the adjacent spinous processes
- —WEAK; membranous
Whats the first palpable spinous process in 70% of people?
- C7
What is a special ft of C1; the Atlas?
- does not have a body/ spinous process
- has a POSTERIOR arch and an anterior arch
What does the axis have?
- an Odontoid process
- –projects superiorly
What do the altanto-occipital joints responsible for?
- FLEXION and EXTENSION of the neck
- little LATERAL flexion and ROTATION
Where the contact in the atlanto-occipital joints?
- between the occipital CONDYLES and the superior articular facets of the atlas
- —synovial joints sith LOOSE capsule
What are the articulations between the atlanto-axial joints like?
- all synovial
- 2 between the inferior ARTICULAR facets of the atlas and the superior articular facets of the axis
- 1 between the anterior arch of the atlas and the odontoid process of the axis
Main movement of the atlanto-axial joints=
ROTATION
Where is the caudal anaesthesia injected ?
- in to the SACRAL hiatus, into the epidural space
- —anesthetise the sacral spinal nerve roots of the Cauda Equina
Where does the spinal cord start and end?
- begins at the FORAMEN MAGNUM (continuous with the Medulla Oblongata)
—ends at the L1/L2
(or anywhere between T12 and L3)
What is the spinal cord surrounded by?
- 3 layers of the meninges
- a epidural fat
What is a laminectomy?
- ## to access the spinal canal (posterior exposure of spinal cord and/or spinal roots)
Why is a laminectomy performed?
- –helps relieve pressure on spinal cord or nerve roots
d. t tumor/ herniated disc/ bone hypertrophy
List the layers
skin> superficial fascia> aponeurotic origin of TRAPEZIUS/thoracolumbar fascia of latissimus dorsi> intrinsic muscles> ligaments (flavum/ supraspinous/ interpsinous)> lamina> spinous process
