Anatomy of back

1. ANATOMY OF SPINEANATOMY OF SPINE

2. OUTLINEOUTLINE
 Conceptual overview
 Regional anatomy
 Surface anatomy
 Radiological anatomy

3. Conceptual overviewConceptual overview
 Functions
Support
Movement <additive>
Protection of central & peri nervous systems
 flexion
 extension
 lateral flexion
 rotation, and
 circumduction

4. curvescurves
Sec curvature bring the center
of gravity to a vertical line,
which allows the body’s weight
to be balanced on the vertebral
column in a way that expends
the least amount of muscular
energy to maintain an
upright bipedal stance.

5. Conceptual overviewConceptual overview
Component parts
Bones
Muscles –Extrinsic- sup,inter; Intrinsic- deep
Vertebral canal
Spinal nerves
Dermatomes and myotomes

8. Conceptual overviewConceptual overview
Key features
Long vertebral column, short spinal cord
Intervertebral foramina and spinal nerves
Innervation of back

9. Regional Regional
anatomyanatomy

10. Intervertebral DiscsIntervertebral Discs

11. LigamentsLigaments
Supraspinous This runs between the tips of adjacent spines.
Interspinous : This connects adjacent spines.
Intertransverse: These run between adjacent transverse processes.
Ligamentum flavum : This connects the laminae of adjacent vertebrae.
cervical region= supraspinous and interspinous ligaments greatly
thickened to form the strong ligamentum nuchae.

12. LigamentsLigaments

13. Dislocations and fractures of
the vertebral column.
A. Unilateral dislocation of the fifth or the
sixth cervical vertebra. Note the forward
displacement of the inferior articular
process over the superior articular process
of the vertebra below. B. Bilateral
dislocation of the fifth or the sixth
cervical vertebra. Note that 50% of
the vertebral body width has moved
forward on the vertebra below. C.
Flexion compression–type fracture
of the vertebral body in the lumbar
region. D. Jefferson's-type
fracture of the atlas. E.
Fractures of the odontoid
process and the pedicles
(hangman's fracture) of the
axis.

14. A. Arrangement of the A. Arrangement of the
deep muscles of the deep muscles of the
back. B. Lateral view of back. B. Lateral view of
the skeleton showing the skeleton showing
the line of gravity. the line of gravity.
Because the greater part of the Because the greater part of the
body weight lies anterior to body weight lies anterior to
the vertebral column, the deep the vertebral column, the deep
muscles of the back are muscles of the back are
important in maintaining the important in maintaining the
normal postural curves of the normal postural curves of the
vertebral column in the vertebral column in the
standing position.standing position.

15. MusclesMuscles
Trap, Lat dorsi, Lev scap, Rho maj & min
Serratus posterior sup & inf
 Deep
Superficial Vertically Running Muscles
Intermediate Oblique Running Muscles
Deepest Muscles
Interspinales
Intertransversarii

18. Muscular triangles of backMuscular triangles of back
Auscultatory Triangle
The auscultatory triangle is the site on the back where breath
sounds may be most easily heard with a stethoscope. The
boundaries are the latissimus dorsi, the trapezius, and the medial
border of the scapula.
Lumbar Triangle
The lumbar triangle is the site where pus may emerge from the
abdominal wall. The boundaries are the latissimus dorsi, the
posterior border of the external oblique muscle of the abdomen,
and the iliac crest.

19. Deep Fascia of the Back Deep Fascia of the Back
(Thoracolumbar Fascia)(Thoracolumbar Fascia)
The lumbar part of the deep fascia is situated in the interval between
the iliac crest and the 12th rib. It forms a strong aponeurosis and
laterally gives origin to the middle fibers of the transversus and the
upper fibers of the internal oblique muscles of the abdominal wall
Medially, the lumbar part of the deep fascia splits into three lamellae.
The posterior lamella covers the deep muscles of the back and is
attached to the lumbar spines. The middle lamella passes medially, to
be attached to the tips of the transverse processes of the lumbar
vertebrae; it lies in front of the deep muscles of the back and behind
the quadratus lumborum. The anterior lamella passes medially and is
attached to the anterior surface of the transverse processes of the
lumbar vertebrae; it lies in front of the quadratus lumborum muscle.

20. Blood Supply of the BackBlood Supply of the Back
Arteries
◦In the cervical region, branches arise from the occipital artery, a branch
of the external carotid; from the vertebral artery, a branch of the
subclavian; and from the deep cervical artery, a branch of the
costocervical trunk.
◦In the thoracic region branches arise from the posterior intercostal
arteries.
◦In the lumbar region branches arise from the subcostal and lumbar
arteries.
◦In the sacral region branches arise from the iliolumbar and lateral sacral
arteries, branches of the internal iliac artery.
Veins
◦The veins draining the structures of the back form plexuses extending
along the vertebral column from the skull to the coccyx.
◦The external vertebral venous plexus lies external and surrounds the
vertebral column.
◦The internal vertebral venous plexus lies within the vertebral canal but
outside the dura mater of the spinal cord.

21. Lymph Drainage of the BackLymph Drainage of the Back
The deep lymph vessels follow the veins and drain into the deep
cervical, posterior mediastinal, lateral aortic, and sacral nodes.
The lymph vessels from the skin of the neck drain into the
cervical nodes,
from the trunk above the iliac crests drain into the axillary
nodes, and those
from below the level of the iliac crests drain into the superficial
inguinal nodes

22. RelationRelation
Vertebrae Spinal Segment
Cervical Add 1
Upper thoracic Add 2
Lower thoracic (T7 to 9) Add 3
Tenth thoracic L1 and 2 cord segments
Eleventh thoracic L3 and 4 cord segments
Twelfth thoracic L5 cord segment
First lumbar Sacral and coccygeal cord segment

23. Posterior views of vertebral bodies in the
cervical and lumbar regions showing the
relationship that might exist between the
herniated nucleus pulposus and the spinal
nerve roots. Note that there are eight cervical
spinal nerves but only seven cervical
vertebrae. In the lumbar region, for example,
the emerging L4 nerve roots pass out laterally
close to the pedicle of the fourth lumbar
vertebra and are not related to the
intervertebral disc between the fourth and
fifth lumbar vertebrae. E. Pressure on the L5
motor nerve root produces weakness of
dorsiflexion of the ankle; pressure on the S1
motor nerve root produces weakness of plantar
flexion of the ankle joint.

24. SPINAL CORD INJURY WITHOUT RADIOLOGICAL ABNORMALITY:
‘SCIWORA’
This is particularly liable to occur if the vertebral canal is
abnormally narrowed, usually by osteoarthritic changes.

25. Surface Surface
anatomyanatomy

26. Surface Surface
anatomyanatomy

32. Thank you!Thank you!