Download MBBS (Bachelor of Medicine and Bachelor of Surgery) Latest Lumbar Vertebrae Lecture PPT
OBJECTIVES:
General features
Classification: Typical and
atypical
Ossification
Applied anatomy
General features:
Lumbar vertebrae have massive body.
Vertebral foramen is triangular.
Spine is quadrangular.
Superior articular facet is concave.
Inferior articular facet is convex.
Posteroinferior part of root of transverse
process has a rough elevation called
accessory process.
CLASSIFICATION:
Total no of lumbar vertebrae: 5
Typical: First to fourth.
Atypical: Fifth.
TYPICAL LUMBAR VERTEBRAE (L1-L4)
BODY:
Large.
Transverse diameter > anteroposterior diameter.
Attachments:
1. To upper and lower borders:
a) Anterior longitudinal ligament (ALL): in front.
b) Posterior longitudinal ligament (PLL): behind.
2. Crura of diaphragm: Either side of ALL.
Right crus: upper 3 lumber vertebrae
Left crus: upper 2 lumber vertebrae
3. Behind the crura of diaphragm: Psoas major muscle arises
from all 5 lumber vertebrae.
VERTEBRAL FORAMEN:
Triangular in cross section.
Larger than those in
thoracic vertebrae but
smaller than in cervical
vertebrae.
Lower part of spinal cord
(Conus medullaris): L1
Dura mater and
arachnoid mater: L1-L5
Cauda equine: L2-L5
VERTEBRAL ARCH:
PEDICLES:
? Short and strong.
? Inferior vertebral
notches are
deeper than the
superior.
? Formation of
intervertebral
foramen.
? Traversed by
spinal nerves and
radicular vessels.
VERTEBRAL ARCH:
LAMINAE:
? Short, strong and
broad.
? Directed
posteromedially.
? Gives
attachment to
ligamentum
flavum.
VERTEBRAL ARCH:
SPINE:
? Quadrilateral
? Projects horizontally backwards.
? Thick along its posterior and
inferior borders.
? Attachments to posterior border:
1. Thoracolumbar fascia
2. Erector spinae
3. Spinalis thoracis
4. Multifidus
5. Supraspinous and infraspinous
ligaments
VERTEBRAL ARCH:
TRANSVERSE PROCESS:
? Tapering and thin.
? Homologous with ribs.
? Accessory process:
rough elevation on the
posteroinferior aspect
of each transverse
process. It gives
attachment to
intertransverse
ligament.
VERTEBRAL ARCH:
ARTICULAR PROCEESS:
? Superior articular facet: concave
& faces medially. Its posterior
border has a rough elevation
called mammillary process which
corresponds to superior tubercle
of 12th thoracic vertebra.
? Inferior articular facet: convex,
laterally.
? Distance between the superior
articular process is relatively
more than inferior articular
process in L1-L3.
? Relation is reversed in L5
? Equal distance in L4.
ATYPICAL LUMBAR
VERTEBRA (L5):
ATYPICAL LUMBAR VERTEBRA/L5:
Body is very large and vertical height of its anterior
surface is greater than its posterior surface.
Transverse process is massive, stout and pyramidal.
Arises mainly from the pedicle and encroaches on
to the body.
Spine is small in size. Its upper border is rounded
and down turned at its dorsal part.
The distance between inferior articular process is
more than superior articular process.
ANTERIOR RELATIONS OF 5TH LUMBAR
VERTEBRA:
1.Both common iliac arteries.
2.Both common iliac veins.
3.Formation of inferior vena cava.
4.Median sacral vessels.
5.Sympathetic trunk.
FAWCETT'S RULE:
OSSIFICATION:
PRIMARY CENTERS: 3 (1 for body and 1 for
each half of vertebral arch)
APPEARANCE: 9-16 weeks of IUL.
FUSION:
? Each half of vertebral arch with each other :- 1
year.
? Vertebral arch with body:- 3-6 years.
9
OSSIFICATON:
SECONDARY CENTERS:
? 5 (1 each for annular epiphyseal ring (upper and lower
surface of body).
? 1 each: tip of transverse process
? 1 for tip of spine.
APPEARANCE: puberty
FUSION: 25 years.
2 Additional centers appear, 1 for each mammillary process.
APPLIED ANATOMY:
1. SACRALIZATON:
Fusion of L5
with sacrum.
Transverse
process of L5
may articulate
with ala of
sacrum and
compress the L5
spinal nerve.
SPINA BIFIDA:
It occurs due to non
fusion of two halves
of the vertebral arch.
Meninges and spinal
cord are exposed
and may herniate out
in midline through the
gap.
CAUDA EQUINA
SYNDROME:
Due to compression of
cauda equina (L2-S1)
Clinical presentation:
1. Flaccid paraplegia
2. Saddle shaped
anaesthesia
3. Bladder and bowel
involvement
4. Impotence
5. Absence of knee and
ankle reflex
THANK YOU.
This post was last modified on 30 November 2021