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Copy Right- Hongqi ZHANG-Department of Anatomy-Fudan University
Systematic Anatomy
(For international students)
Department of Anatomy,Fudan University
Teaching contents
Spinal cord
Dr.Hongqi Zhang (张红旗)
Email: [email protected]
Copy Right- Hongqi ZHANG-Department of Anatomy-Fudan University
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Copy Right- Hongqi ZHANG-Department of Anatomy-Fudan University
Systematic Anatomy
(For international students)
Department of Anatomy,Fudan University
Teaching contents
Spinal cord
Dr.Hongqi Zhang (张红旗)
Email: [email protected]
Copy Right- Hongqi ZHANG-Department of Anatomy-Fudan University
2
Copy Right- Hongqi ZHANG-Department of Anatomy-Fudan University
Spinal cord
Copy Right- Hongqi ZHANG-Department of Anatomy-Fudan University
Central nervous system (CNS)
Brain
Telencephalon
Diencephalon
Cerebellum
Brain stem
1-Midbrain
2-Pons
3-medulla oblongata
Spinal cord
Position of the Spinal Cord
 Position: Lies in vertebral canal, 45cm long
approximately
 Upper end: Continuous with medulla
oblongata at foramen magnum
 Lower end: at the lower border of L1 in adult;
at newborn at level of L3
 Sexual difference: usually a little lower in
female than in male
 Clinic significance: anaesthesia done usually
at below the L1
Copy Right- Hongqi ZHANG-Department of Anatomy-Fudan University
Anaesthesia in the vertebral canal
L1
Lower end
Of spinal cord
Skin
Subcutaneous fascia
Supraspinal lig.
Interspinal lig.
Yellow lig.
Needle
puncture
Draw cerebrospinal fluid
From the vertebral canal
For lab examination
Copy Right- Hongqi ZHANG-Department of Anatomy-Fudan University
External Features of Spinal Cord
 External feature:
A long cylindrical structure & slightly
flattened anteroposteriorly
 Two enlargements
Cervical enlargement
corresponds to the C4 to the T1 segments
Lumbosacral enlargement
corresponds to the L2 to the S3 segments
 Conus medullaris
 Filum terminale-only thin filament
 Cauda equina
Fudan university Zhang Hongqi 张红旗
Lumbosacral
enlargement
Conus medullaris
Filum terminale
Cauda equina
Conus medullaris and cauda equina
External Features of Spinal Cord
Fissure and sulci
1 - Anterior median fissure
2 - Posterior median sulcus
3 - Anterolateral sulcus - connect with ant.root (motor)
4 - Posterolateral sulcus - connect with post.root (sense)
2
4
Post.root
Spinal
ganglion
Post.branch
Ant.root
1
3
Ant.branch
Segments of Spinal Cord
 A portion of the cord that
gives rise to a pair of spinal
nerve constitutes a
segment.
 There are 31 segments
8 cervical ss
12 thoracic ss
5 lumbar ss
5 sacral ss
1 coccygeal s
Segment - s
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Relationship of SC Segments to Vertebral body
In the third month of fetal life,
the spinal cord occupies the
entire length of the vertebral
canal.
After that time,there are some
difference between spinal
cord & vertebral canal in
growth speed,that is, the
vertebral canal grow faster
than that of spinal cord,
Spinal cord
Vertebral
canal
Sc length = vertebral canal
At 3rd fetal month
Copy Right- Hongqi ZHANG-Department of Anatomy-Fudan University
Copy Right- Hongqi ZHANG-Department of Anatomy-Fudan University
Relationship of SC
Segments to Vertebrae
At birth
The inferior ends is
below at the lower
border of L1 in adult;at
birth at level of L3,
usually a little lower in
female than in male.
L3
But each spinal nerve
have to come out from
their corresponding
intervertebral foramina.
Sc inf. end is
At the level of
L 1 at adult
Sc inf. end is higher
Than that of canal
At birth
After 3rd month
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of Anatomy-Fudan University
Copy Right- Hongqi ZHANG-Department of Anatomy-Fudan University
More high level
More almost horizental.
More lower level
More obliquity
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Relationship of SC Segments to Vertebral Numbers
Spinal segments
Vertebral levels (spines)
Upper cervical region (C1~C4)
Lie opposite the corresponding vertebrae
Lower cervical and upper
thoracic region (C5~8；T1-4)
One lower in number than corresponding
vertebrae
Middle thoracic region (T5~T8) Two lower in number than corresponding
vertebrae
Lower thoracic region (T9~T12) Three lower in number than corresponding
vertebrae
Lumber segments
T10~T12
Sacral and coccygeal segments
L1
Relationship of SC Segments to Vertebral Numbers
Spinal segments
Upper cervical region (C1~C4)
Vertebral levels (spines)
= C1 ~ C4
Lower cervical and upper thoracic －1 = C4 ~ T3
region (C5-8；T1~4)
Middle thoracic region (T5~T8)
－2 = T3 ~ T6
Lower thoracic region (T9~T12)
Lumber segments
－3 = T6 ~ T9
= T10 ~ T12
Sacral and coccygeal segments
= L1
Internal structure of spinal cord
C
1 - Gray matter
2 - White matter
3 – reticular formation
1
T
2
L
3
S
C-cervical;T-tharacic;L-lumbar;S-sacral
Central canal
Internal structure of spinal cord
Fasciculus gracilis
Fasciculus cuneatus
Lat. spinothalamic tract
Nucleus proprius
Lat.corticospinal tract
Gray matter
Post.root
Motor neuron of ant.horn
White matter
Spinal ganglion
Spinal pia matar
Spinal n.
Spinal arachnoid
Spinal dura matar.
Ant.root
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Gray matter of Spinal Cord
Like a butterfly or letter “H”
Consist of cell body,neuroglia and dendrite
Located around the central canal
Post. horn (column)
Intermediate zone
Post. gray commissures
Ant. gray commissures
Ant. horn (column)
Copy Right- Hongqi ZHANG-Department of Anatomy-Fudan University
Gray Matter of Spinal Cord
Anterior horn (column)
Posterior horn (column)
Lateral horn (column)
is present in the thoracic
& upper lumber segments
of the cord (T1-L3) only
Intermediate zone
Ant. gray commissures
Post. gray commissures
Gray Matter of Spinal Cord
Posterior horn (column):
 1- Marginal layer
 2- Substantia gelatinosa
Situated at the apex of posterior horn throughout the length of
spinal cord. Receives fibers are associated with the senses cord.
 3- Nucleus proprius
Situated anterior to the substantia gelatinosa throughout the
length of spinal cord. Concerns the sensations of pain and
temperature
1
2
3
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Gray Matter of Spinal Cord
Posterior horn (column):
 Nucleus thoracicus (lable A)
Situated at the base of posterior horn and extending
from segments C8~L3. Associated with proprioceptive
endings
A
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Intermediate zone
 Intermediolateral nucleus (labeled 1)
Extends from segments T1~L3,
Containing sympathetic preganglionic neurons
 Sacral parasympathetic nucleus
Extends from segments S2~S4,
Containing parasympathetic preganglionic neurons
1
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Intermediate zone
 Intermediomedial nucleus (labled A)
Throughout the whole length of spinal cord.
Associated with receiving viscera afferent information
A
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Copy Right- Hongqi ZHANG-Department of Anatomy-Fudan University
Anterior horn (column):
 Two groups of nuclei
1-Medial nuclear group: present in most segments of
spinal cord, innervating axial (trunk) muscles
2-Lateral nuclear group: present only in cervical and
lumbosacral enlargements, innervating limb skeletal
muscles
1
2
Copy Right- Hongqi ZHANG-Department of Anatomy-Fudan University
Anterior horn (column): labeled with red color
 three kinds of neurons (motor neuron 2)
 α- motor neuron: large multipolar neuron, innervates
skeletal muscles, producing contraction of muscles
 γ- motor neuron: smaller multipolar neuron, innervates
intrafusal muscle fibers of neuromuscular spindles,
regulating muscular tonus
 Interneuron —Renshaw’s
cell: negative feedback
Rexed’s lamina
 Posterior horn is formed by lamina Ⅰ to Ⅵ；
 Intermediate zone is corresponding to lamina Ⅶ；
 Anterior horn is composed laminae Ⅷ and Ⅸ；
 lamina Ⅹ is the gray matter around the central canal.
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Right- Hongqi
ZHANG-Department
Anatomy-Fudan
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Important
Subdivision
of SpinalofCord
Gray Matter
laminae
nuclei
Ⅰ
Posterior marginal nucleus
Ⅱ
Substantia gelatinosa
ⅢⅣ
Nucleus proprius
Ⅴ
Reticular nucleus
Ⅵ
Base of posterior column
Ⅶ
Thoracic nucleus
Intermediomedial mucleus
Intermediolateral nucleus
Sacral parasympathetic nucleus
ⅧⅨ
Medial motor neuron column
Lateral motor neuron column
Ⅹ
gray matter around central canal
Copy Right- Hongqi ZHANG-Department of Anatomy-Fudan University
Copy Right- Hongqi ZHANG-Department of Anatomy-Fudan University
White matter of spinal cord
Organization
Nerve fiber (tract)
Around the grey matter
Three parts
Ant. Funiculus (A.F)
Lat. Funiculus (L.F)
Ascending & descending fiber
Post. Funiculus (P.F)
Ascending fiber only
White commissure
Ant.commissure of WM
Post.commissure of wm
P.F
L.F
A.F
matter
CopyWM-white
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ZHANG-Department of Anatomy-Fudan University
White Matter of Spinal Cord
White matter contains three kinds of fibers: ascending,
descending and fasciculus proprius
Post. funiculus
Post. white commissure
Lat.
funiculus
Ant. funiculus
Ant. white commissure
Copy Right- Hongqi ZHANG-Department of Anatomy-Fudan University
White matter of spinal cord
Fiber tract:
in CNS, fiber bundle which has similar origin, terminal,
course and function.
Ascending tract:
to conduct the sensory impulse from the trunk and
limbs to the brain.
Descending tract.
to convey the motor information from central nervous
system to the trunk and limbs.
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Copy Right- Hongqi ZHANG-Department of Anatomy-Fudan University
White matter of spinal cord
Nomenclature :
Course: pyramid tract
Origin and terminal : Corticospinal tract.
Spinothalamic tract
Appearance of the tract: Fasciculus gracilis
General: lateral corticospinal tract.
Fasciculus proprius: both origin & termination of
the fascisulus are in the spinal cord.with two
direction (ascending & descending), the function
take part in different segment reflex.
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Major Ascending or sensory Tracts
Fasciculus gracilis
Fasciculus cuneatus
Pos. spinocerebellar tract
Ant. spinocerebellar tract
Spinothalamic tract
Lat.Spinothalamic tract(rough tonch)
Ant.Spinothalamic tract(pain,temperature,sensation)
Red color means important
Fasciculus cuneatus
Fasciculus gracilis
Fasciculus gracilis and fasciculus cuneatus
From pain and temperature
And some touch receptors
Spinothalamic tract
Lateral and anterior spinothalamic tract
Summary-ascending tracts
Tract
Site of origin
Funiculu
s
Termination
Function
Fasciculus
gracilis
Spinal ganglia
below segment
T5
Posterior
Gracile
nucleus
Conscious proprioceptive
(vibratory sense, and muscle
joint sense) and fine touch
sensation of trunk and limbs
Fasciculus
cuneatus
Spinal ganglia
above segment
T4
Posterior
spinocerebellar
tract
Homolateral
nucleus
thoracicus
Anterior
spinocerebellar
tract
Contralateral
Laminae
Ⅴ~Ⅶ
Lateral
Spinothalamic
tract
Laminae
Ⅰ, Ⅳ~Ⅶ
anterior
Spinothalamic
tract
Cuneate
nucleus
Lateral
Cerebellum
Unconscious proprioception
from limbs and trunk
Lateral
Dorsal
thalamus
Pain, temperature and crude
touch sensation of trunk and
limbs
anterior
Descending Tracts
Lateral corticospinal tract
Fasciculus proprius
Rubrospinal tract
Medial longitudinal
fasciculus
Reticulospinal tract
Vestibulospinal tract
Tectospinal tract
Anterior corticospinal tract
Red color means important content
Lateral and anterior corticospinal tract
Coranal section of cerebrum
horizental section of cerebrum
horizental section of midbrain
horizental section of pons
Lateral
corticospinal
tract
Anterior
corticospinal
tract
horizental section of
medulla ablongata
horizental section of
spinal cord
Summary - descending tracts
Tract
Site of origin
Funiculus
Lateral
corticospinal
Cerebral cortex
Lateral
Anterior
corticospinal
Cerebral cortex
Anterior
Rubrospinal
Red nucleus
Vestibulospinal
Reticulospinal
Termination
Function
Laminae (Ⅳ~Ⅸ)
anterior horn
Motor neurons &
interneurons
Voluntary movement
of skeletal muscle of
trunk and limbs
Lateral
Laminae (Ⅴ~Ⅶ)
anterior horn
Motor neurons
& interneuron
(for flexor)
Facilitates activity of
flexor muscles
Homolateral
vestibular nuclei
Anterior
Laminae (Ⅶ~Ⅷ)
anterior horn
Motor neurons
& interneuron
(for extensor)
Facilitates activity of
extensor muscles
Reticular
formation
Anterior &
lateral
Laminae (Ⅶ~Ⅷ)
Control Voluntary
movement of
skeletal muscle of
trunk & proximal
extremity
Summary - descending tracts
Tract
Site of origin
Funiculus
Termination
Medial
longitudinal
fasciculus
Vestibular
nuclei
Anterior
Laminae (Ⅶ~Ⅷ）
Anterior horn cell
Coordinate of head
and eye movement
Tectospinal
Superior
colliculus
Anterior
Laminae（Ⅵ~Ⅷ）
Reflex head turning
Fasciculus
proprius
Spinal cord
Anterior,
lateral &
posterior
Spinal cord
Function
Intrinsic reflex
mechanism of spinal
cord
Main functions of spinal cord
 Conduction of excitations
bridge; brain - periphery
Sensory impulse to brain
Motor impulse to periphery
 Reflex
Somatic reflex (skeletal m contration)
superficial and deep reflex
Tendon (stretch reflex ) arc
Flexor reflex
Abdominal reflex
Visceral reflex (sm,cardiac m,gland)
Defecation reflex
Carotid reflex
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Spinal cord transverse section lesion
Complete spinal cord transection results in the immediate
Loss of all neural function below the level of the lesion.there
is a complete lose below the level of the lesion of :
All somatic sensation
All motor function
All visceral sensation
All reflex activity
All muscle tone,etc
Spinal shock: last for 1~6 weeks
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Copy Right- Hongqi ZHANG-Department of Anatomy-Fudan University
Hemisection of the spinal cord (brown-sequard syndrome)
sensation
2 1
Injured main sensory
fasiculus：
1-Fasciculus gracilis
2-Fasciculus cuneatus
3
3
3-Spinothalamic tract
motor
Injured motor fasiculus：
4
4 - Lat.corticospinal tract
5
5 - Ant.corticospinal tract
Right:deep sensation,limb paralysis
Left
:superficial
sensation disfunction
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ZHANG-Department
of Anatomy-Fudan University
Copy Right- Hongqi ZHANG-Department of Anatomy-Fudan University
Hemisection of the spinal cord
Brown-sequard syndrome
Result in:
The ipsilateral motor neuron paralysis below the level of lesion
Resulted from damage to the ipsilateral corticospinal tract.
Loss of the ipsilateral deep sensation (proprioceptive,vibratroy
and two–point discrimination sense)below the level of lesion .
resulted from damage to the fasciculus gracilis and fasciculus
cuneatus.
Loss of the contralateral superficial sensation (pain & thermal
Sense)below the level of lesion. resulted from damage to the
lateral spinothalamic tract.
Copy Right- Hongqi ZHANG-Department of Anatomy-Fudan University
Copy Right- Hongqi ZHANG-Department of Anatomy-Fudan University
Lesion of anterior horn of the spinal cord
It causes ipsilateral lower motor neuron
paralysis in the segments of the lesion (resulting
from damage to lower motor neurons)such as
infantile paralysis (Poliomyelitis).
Usually it is caused by poliomyelitis virus
Motor neuron
Copy Right- Hongqi ZHANG-Department of Anatomy-Fudan University
Copy Right- Hongqi ZHANG-Department of Anatomy-Fudan University
Meningocele
cleft spine
Meningocele
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Copy Right- Hongqi ZHANG-Department of Anatomy-Fudan University
Copy Right- Hongqi ZHANG-Department of Anatomy-Fudan University
FIGURE 3.1.3
At upper thoracic and all cervical levels the dorsal funiculus is further
subdivided, as shown here This view also shows the named sulci, fissures
Hongqi
ZHANG-Department
of Anatomy-Fudan
University
and Copy
septi,Rightas well
as the
course taken by entering
and departing
axons.
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FIGURE 3.1.4
Most of the structures labeled on
these slides are ones you have
identified in earier views of this
module. Try to reconcile the
appearance of the structure here
with that in views of the brain's
surface. All the sections, except
the 3 spinal cord ones, are
clickable. Clicking on one leads
you to enlarged view of the
section.
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Copy Right- Hongqi ZHANG-Department of Anatomy-Fudan University
answer 9
1intermediolateral
cell column
2 - dorsal
funiculus
3 - lateral
funiculus
4 - ventral
funiculus
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Copy Right- Hongqi ZHANG-Department of Anatomy-Fudan University
The end!
Hardworking
Harvest
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