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Transcript
Vertebral Column
Osteology
 7 C, 12 T, 5 L, 5 S (Fused as Sacrum), 4
coccygeal
 Primary Curves
 Secondary Curves
 Anterior/Posterior alignment
Primary Curve
Vertebral Segments
A-P View
Secondary Curves Lateral
Vertebral Column
Osteology
 Typical Vertebrae
 Body
– Superior and inferior surfaces of body (plateaus)
– Thickened around the rim, location of epiphyseal plates
– Cartilaginous end-plates
 Vertebral Arch
– Pedicles, Laminae
– Transverse Processes
– Spinous Process
– Facets – superior articular and inferior articular
 Spinal Foramen
 Intervertebral Foramen
Typical Vertebrae
Typical Vertebrae
Typical Lumbar
Typical Thoracic
Typical C
Sacrum and Coccyx
Vertebral Relationships
Arthrology
 Intervertebral Discs
 Fibrocartilaginous joints
 Increase in size from C to L (3mm to 9 mm)
 Ratio remains the same
 Make up 20-30% of length of column
Intervertebal Discs
Discs
Discs
Arthrology
 Two Components
 Outer rim of fibrocartilage called the anulus
fibrosus (attaches to cartilaginous end plate)
 Connects vertebral bodies in a
fibrocartilaginous joint (no capsule, little
motion)
Arthrology
 Anulus encloses a central mass called the
nucleus pulposus
 About 80-90% water, less with increased
age
 Contains a mucopolysaccharide matrix
 Changes shape, releases and absorbs water.
Thicker in AM than PM
 Neither blood vessels or nerves penetrate
nucleus
Arthrology
 Structure deforms when pressure is put on
vertebral column as in weight bearing
 Acts as a shock absorber
 Annulus totally encloses the nucleus and
keeps it under constant pressure
 As you get older, the H2O content decreases
and the nucleus becomes more
fibrocartilaginous, therefore less easily
deformable and more easily damaged
Arthrology
 Nucleus, when under extreme pressure, can
herniate or extrude from the disc in a
posterior or posterior-lateral direction
 Usually occurs in cervical or lumbar region
 Nucleus can put pressure on spinal nerve
causing refereed symptoms (motor and
sensory)
 Can cause pressure on cord itself if true
posterior
Vertebral Relationships
Arthrology
 Facet Joints (Typical)
 Superior articular facets of one vertebrae with
inferior facets of vertebrae above
 Synovial gliding joints
 Surrounded by joint capsule and small capsular
ligaments
 The type and amount of motion in any given part
of the spine is dictated by the orientation of the
articular facets as well as the fluidity, elasticity
and thickness of the intervertebral discs
Facet Joints (C and T)
Facets L
Arthrology
 Typical movements in sections of the spine
 Lumbar
 Thoracic
 Cervical
Major Ligaments of the Spine
 Anterior Longitudinal Ligament
 Dense band along anterior and lateral surface of
the vertebral bodies from C2 to sacrum
– Superficial - bridge several vertebrae
– Deep – short, run from V to V, blends with fibers of
anulus fibrosus
– Limits extension of V column
 From C1 to skull, called Atlanto-Occipital
Membrane
ALL
Atlanto-Occipital Membrane
A and P Longitudinal Ligament
Major Ligaments
 Posterior Longitudinal Ligament
– Runs along posterior surface of vertebral bodies
(anterior to spinal canal)
– C2 to Sacrum
– Short fibers attach ligament to posterior disc,
reinforce disc posteriorly
 Superiorly, continues to occiput, called
Tectorial Membrane
 Limits flexion
PLL
Tectorial Membrane
Ligaments
 Supraspinous
– Spinous process to spinous process – tip to tip
– C7 to sacrum
 Limits flexion
 In cervical region, becomes much thicker
with a greater elastic content
 Called Ligamentum Nuchae
Supraspinous
Ligamentum Nuchae
Ligaments
 Interspinous
 Found between spinous processes
 Most well developed in lumbar region
 support
Interspinous
Interspinous
Ligaments
 Ligamentum Flavum
 Connects lamina of one to lamina of the
other
 Found from axis to sacrum
 Limit flexion
 Continuation to the skull is called Posterior
Atlanto-Occipital membrane
Ligamentum Flavum
Atlanto-Occipital MembranePosterior
Ligaments
 Intertransverse
 Only well-developed in Lumbar Region
 Between transverse processes
 Limit lateral flexion
Special Joints of Spine
 Lumbo-Sacral
– L5 and S1 (or sacrum)
– Drastic change from lordotic to kyphotic curve
– Strong “shearing forces”
– The sacral segment is inclined anteriorly and inferiorly
forms an angel with the horizontal called the lumbosacral angle
 Angle can be increased significantly with an
increase in lumbar curve
 During flexion/extension the greatest mobility of
the spine occurs between L5 and S1
L5/S1
Lumbo-Sacral Jt.
L5/S1
 Spondylolysis – a developmental anomaly
of the lamina wherin a bony defect
separates the sup. and inf. Articular
processes thus separating the post. Part of
the neural arch from the ant. Arch and the
vertebral body
 Usually asymptomatic, very common in
males
S and S
L5/S1
 Spondylolistheses – an anterior movement
of the L5 vertebral body and can cause
compression of the cauda equina which
rests posteriorly
Sacralization
 Where 5th lumbar vertebrae takes on
characteristics of the sacrum and may be
partially or completely fused with sacrum
Lumbarization
 Superior aspect of the sacrum assumes
characteristics of the 5th lumbar vertebrae
S-I Joint
 Review Hip Bone AKA Innominate AKA
Os Coxae
 Ilium, Ischium and Pubis
 Fuse at Puberty
 Acetabulum
 Pelvis = 2 coxal bones the sacrum and
coccyx
Innominate Bone AKA Hip
Sacrum
Pelvis
Female Pelvis
S-I
 Auricular surface of ilium with auricular
surface of sacrum-Little movement
 Joint under relatively constant pressure to
rotate anteriorly based on anatomical design
 Upper part of joint is not synovial, is fibrous
held in place by tough Interrosseous S-I
ligaments – helps limit anterior motion
S-I Joint
S-I Joint
S-I Joint
S-I – Synovial Aspect of Joint
 Major Ligaments – mostly designed to prevent
ant. motion
 Posterior S-I – runs down and medially from ilium
to sacrum
 Iliolumbar – L4 and 5 transverse processes to
posterior iliac crest
 Anterior S-I – ilium to sacrum
 Sacrotuberous – iliac tuberosity and post. Surface
of lower sacrum to ischial tuberosity
 Sacrospinous – lateral borders of lower sacrum
and coccyx to attach to the spine of ischium
S-I Joint
S-I Joint
Pubic Symphysis
 Anterior connection of pelvis
 Fibrocartilaginous joint
 Limited motion
 Motion increase dramatically during
pregnancy, especially at the time of birth
 Similar increase in SI joint mobility at this
time
Pubic Symphysis
Atlanto-Axial Joint
 Atlas and Axis
 Pivot
 Two convex superior facets of axis with two
concave inferior facets of the atlas
 Atlas also posses a facet on the internal surface of
the anterior arch which articulates with the dens of
the axis
 Major ligaments form spine support – Ant.
Atlanto-Occipital, Tectorial Membrane, Post. A-O
C1/C2
C1/C2
C1/C2
A-A Joint
 Alar – from dens to occiput
 Transverse - around dens
 Cruciate
– Sup. Longitudinal Band
– Inferior Longitudinal Band
– Transverse
Atlanto-Occipital Joint
 Two concave superior facets of atlas
articulate with two convex surfaces of
occipital condyles of the skull
 Supported by major ligaments
 Small saddle joint
 Very limited motion – nodding type motions
in all directions.
Atlanto-Occipital
Atlanto-Occipital