Spinal anatomy

1. ANATOMY OF
VERTEBRAL COLUMN
AND SPINAL CORD
MODERATOR : DR NIDHI
PRESENTOR : DR RITIKA PG1

2. THE VERTEBRAL COLUMN
. The vertebral column also known as spine ,spinal column or backbone.
. It supports body weight & transmits it to the ground through lower limbs.
. Spine is composed of vertebral bones and intervertebral disc.
. About 71 cm in adult male .
. About 61 cm in adult female.
. The intervertebral disc contribute 1/5th of the length of the vertebral column.

3. TOTAL VERTEBRAE= 33

4. 7 Cervical (C)
12 Thoracic (T)
5 Lumber (L)
5 Sacral (S)
4 Coccygeal

5. At each vertebral level,
paired spinal nerves exit
the CNS.

6. In thoracic ,lumbar & sacral
regions, the no. of vertebrae
corresponds to the number of
spinal nerves, each nerve lying
below the corresponding
vertebra.

7. In the cervical region, there are
8 nerves, the upper 7 lying
above the corresponding
vertebrae & 8th below the
seventh vertebra.

8. In the coccygeal region ,there
is only one coccygeal nerve.

10. VERTEBRAL COLUMN

11. The cervical, thoracic &
lumbar vertebrae -
movable.
Sacrum & coccyx -
immovable

12. The 1st cervical vertebra is
called ATLAS.
. No body
. No spine
. Anterior arch & posterior
arch
The 2nd cervical vertebra is
called AXIS. It has odontoid
process(dens).

13. All 12 thoracic vertebrae
articulate with their
corresponding ribs.
Lumbar vertebrae have
large anterior cylindrical
vertebral body.

14. Thoracic vertebra
. Heart shaped body
. Long, thin, vertical spine
. Round vertebral foramen
. Body/foramen ratio is 2
. Has impression for rib
articulation

15. Lumbar Vertebra
. Kidney shaped body
. Short,thick,horizontal spine
. Body/foramen ratio is 3-4
. No impression for rib articulation

18. Sacrum

19. The thoracic and sacral
curves are called primary
curves.
The cervical and lumbar
curves are called secondary
curves.
All curves are fully
developed by age 10.

20. Newborn spinal
curvature:
C shape
Single curve
Adult spinal curvature:
S shaped vertebral column
4 curves
Secondary curvatures develop after birth.

23. Cervical & Lumber curve
are convex( bulging out).
The thoracic & sacral
curves are concave
(cupping in).

25. FUNCTIONS OF THE VERTEBRAL COLUMN
1. Supports head.
2. Help maintain balance in the upright position.
3. Enclose and protect the spinal cord.
4. Permits movements .
5. Absorb shock during walking.
6. Serve as a point of attachment for the ribs,pelvic girdle and muscles of the back and upper
limbs.

26. NERVOUS SYSTEM
The nervous system has 3
functions:
. Collection of sensory input
. Integration
. Motor output

28. STRUCTURAL
CCNS: Brain & Spinal
cord
PNS: Nerves & ganglia
Crainal & spinal nerves

29. FUNCTIONAL
Sensory division(afferent)
Motor division (efferent)
Autonomic
Somatic
sese

31. SPINAL CORD
The main pathway for information connecting the brain and PNS.
It is elongated, cylindrical, suspended in the vertebral canal and protected by vertebrae.
Surrounded by meninges & CSF.
The primary function of spinal cord is a transmission of neural signals between the brain &rest of
the body.
Sensory
Motor
Local reflexes

32. Extends from foramen magnum to
2nd lumbar vertebra.
Continuous above with the medulla
oblongata.
The tapered inferior end forms conus
medullaris.
It is connected to the coccyx called
Filum Terminale.

33. 31 pairs of spinal nerve
8 Cervical
12 Thoracic
5 Lumbar
5 Sacral
1 Coccygeal

34. Has two enlargements:
Cervical enlargement supplies the
upper limbs.
Lumbosacral enlargement supplies
lower limbs.

36. It is 45cm in length.
It extends lower border
of L1&L2 in adults and L3
in children.

37. White matter decreases
from cervical to
lumbosacral and gray
matter increases from
cervical to lumbosacral .

39. SPINAL MENINGES
● PIA MATER : Delicate inner layer
Pia mater forms filum terminale.
● ARACHNOID MATER: It is the middle layer , which is web like structure
filled with csf fluid that cushions the brain.
● DURA MATER: The tough outer layer

40. Spaces
Epidural: contains internal vertebral
venous plexus (batson plexus), blood
vessels, connective tissue & fat.
Subdural: contains serous fluid
Subarachnoid: contains CSF & blood
vessels within web like strands of
arachnoid tissue, cisterns.

42. LIGAMENTS OF THE SPINE
. Anterior spinal ligament
. Posterior spinal ligament
. Tectorial membrane
. Interspinous ligaments
. Supraspinous ligament
. Ligamentum flavum

43. LIGAMENTS OF SPINE

45. LIGAMENTUM FLAVUM
It is consist of right and left halves that join at an angle less than 90 degree.
It is thinnest in cervical and upper thoracic regions.
It is thickest in the lower thoracic and lumbar regions.
Needle advancement is easier to appreciate when needle is introduced at a lower level.
At the L2-L3 interspace, the ligamentum flavum is 3 to 5 mm thick.
,the distance from ligamentum flavum to the spinal meninges is 4-6mm.
Consequently, a midline insertion of an epidural needle at this level is least likely in an
inadvertent meningeal puncture with epidural anesthesia-analgesia.

48. Ventrally, the vertebral
bodies & intervertebral
disc are connected and
supported by the
anterior & posterior
longitudinal ligaments.

49. Dorsally, the
ligamentum
flavum,interspinous
ligament and
supraspinous ligament
provide additional
stability.

50. When we use midline
approach , needle passes
through these 3 dorsal
ligaments and through
oval space present
between bony lamina &
spinous process of
adjacent vertebrae.

51. Nerve blocks close to the
intervertebral foramen carry
a risk of subdural or
subarachnoid injection.

52. . The artery of Adamkiewicz, or arteria
radicularis magna, arising from the
aorta.
. It is typically unilateral & nearly always
arise on the left side.
. It providing the major blood supply to
the anterior 2/3rd of the spinal cord.
Injury to this artery can result in the
anterior spinal artery syndrome.

53. ABNORMAL SPINAL CURVATURE
● SCOLIOSIS
Lateral bending of the vertebral column ,usually in the thoracic region.
● KYPHOSIS
Increase in the thoracic curve of the vertebral column.
● LORDOSIS (Hollow Back)
Increase in the lumbar and cervical curve of the vertebral column.

58. THANK YOU