cervical spondylosi

1. Cervical spondylosis

2. • Cervical spondylosis is the defined as “spinal
canal and neural foraminal narrowing in
cervical spine secondary to multifactorial
degenerative changes
• Approximately 25% of individuals younger
than forty years of age, 50% of individuals
over forty years of age, and 85% of individuals
over sixty years of age have some degree of
disc degeneration

6. • The fibers of the annulus fibrosus that
surround the nucleus pulposus lengthen,
weaken, and fray with age and use, thereby
allowing the disk to bulge posteriorly.
• this “soft-disk” herniation occurs mainly
during the third and fourth decades of life
when the nucleus is still gelatinous.

7. • The disc loses height and bulges posteriorly into
the canal.
• With this loss of height, the vertebral bodies drift
toward one another.
• Posteriorly, there is infolding of the ligamentum
flavum and facet joint capsule, causing a decrease
in canal and foraminal dimensions.
• Osteophytes form around the disc margins and at
the uncovertebral and facet joints.

9. Radradiolgy
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Radiology
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10. • A bulge involves more than half of the
circumference of an intervertebral disc
• protrusion is distinguished from a disc bulge in
that it involves less than half the circumference of
the disc. Conversely it is distinguished from a disc
extrusion in that its base is wider than its 'dome'
and it does not extend above or below the disc
level.
• disc extrusion has a broader dome than neck

11. • The joints between the neural arches are the
zygapophyseal joints or facet joints.
• The branches of the posterior primary rami
innervate these joints.

12. • endplates of the vertebral bodies progressively suffer
mechanical stress with the consequent formation of
osteophytes. These osteophytes are a natural trial to
increase the load-bearing surface of the endplates in
order to compensate for spine hypermobility
secondary to disk degeneration.
• ossification of the posterior longitudinal ligament
(OPLL), most commonly seen in the Asian population,
• osteophytes develop in the vertebral bodies, facet
joints, and arches, and the ligamentum flavum thickens
and ossifies

13. Pathogenesis of Cervical Spondylosis
• intervertebral disc desiccation, which is associated with
increase in the ratio of keratin sulfate to chondroitin
sulfate
• the nucleus pulposus shrinks, loses elasticity, and
becomes more fibrous due the loss of water, protein
and mucopolysaccharides during the aging process
• Disc height is initially lost in the ventral portion of the
disc, which results in a decrease in cervical lordosis
• These early changes ultimately lead to the main
pathophysiological process of cervical spondylosis, a
reduction in sagittal spinal canal diameter

14. • these changes cause a transfer of axial load onto the
facet joints, resulting in hypertrophy of those joints
that further decreases the spinal canal’s diameter
• The annulus fibrosis is thinner dorsally, thus making it
easier for the nucleus pulposus to dissect through and
cause disc herniations into the spinal canal
• Preceding disc herniation, the peripheral fibers of the
annulus fibrosis and Sharpey’s fibers dissect from the
vertebral body edges
• posterior longitudinal ligament beginning to pull away
from the vertebral bodies near the end plates

15. • Where the PLL peels off the dorsal vertebral
body, reactive bone formation begins forming
spondylotic bone spurs
• These osteophytic growths may project into
the intervertebral foramina
• increase in joint motion causes an
acceleration of osteophyte growth, and this is
most pronounced at C5- C6 and C6-C7
• --decrease in sagittal spinal canal diameter,

16. Cervical Spine Posture
• upper cervical spine allows for varying degrees of
motion in multiple directions
• lower parts of the cervical spine do not provide
the same degree of motion. A significant feature
of this part of the spine is the lordotic posture,
and it is believed that this may play a role in
preventing spinal cord injury.
• The facet joints are most effective in participating
in axial load support when in extension

18. axial view of cervical spinal stenosis with spinal cord impingement due to the combination
of a congenitally narrow cervical spinal canal and superimposed cervical spondylosis.
Encroachment on the cervical spinal canal is caused by bulging disks often with
osteophytic spurring, thickening of the posterior longitudinal ligament and ligamenta flava,
subluxation of one vertebra forward or backward on its neighbor, thickening of the
posterior aspect of the uncovertebral joints, and osteoarthritis of the facet joints.

20. Cervical spondylotic myelopathy
• long-tract signs resulting from a decrease in
the space available for the cervical spinal cord
• Anteriorposterior diameter of the spinal canal,
• dynamic cord compression
• dynamic changes in the intrinsic morphology
of the spinal cord
• the vascular supply of the spinal cord.

21. Static Factors
• congenitally narrow cervical spinal canal
• However, dynamic MRI studies of 295 patients with symptomatic CSM by
Morishita and colleagues showed increased segmental mobility in
the cervical spine of patients with a congenitally narrow canal (<13 mm
anteroposteriorly), suggesting that segmental instability may also
contribute to accelerated sp
• Congenital anomalies of the cervical spine such as Klippel-
Feil syndrome can lead to accelerated spondylosis.
• patients who have undergone surgical fusion
of cervical vertebrae can have exaggerated spondylosis in
adjacent segments.
• Both congenital and iatrogenic fusions likely result in
excessive motion of adjacent unfused spinal levels, which
leads to increased spondylosis. ondyl

22. • normal cervical spinal canal sagittal diameter
(posterior vertebral body to spinolaminar line) is
17 to 18 mm (C3–C7) in a white population
• patients with developmentally narrowed
midcervical sagittal diameters smaller than 10
mm were often myelopathic, patients with canals
of 10 to 13 mm were at risk for CSM, canals of 13
to 17 mm were seen in patients with
symptomatic spondylosis but rarely myelopathy,
and subjects with canals larger than 17 mm were
not prone to develop spondylosis.

23. • Acquired cervical central canal stenosis
• age-related spondylotic change (most
common)
• OPLL, and ossification of the ligamentum
flavum

24. Dynamic Factors
• exacerbated by neck motion
• The spinal cord stretches with flexion of the neck and it can be
compressed against osteophytic spurs and intervertebral disks
protruding into the spinal canal.
• Hyperextension can pinch the spinal cord between the posterior
margin of the vertebral body anteriorly and the laminae or
ligamentum flavum posteriorly.
• Repetitive neck movements and trauma can also accelerate
spondylosis.
• An animal study in which rabbits were exposed to repeated forcible
neck extension and flexion movements showed early development
of osteophytes. Similarly, rugby players and patients with dystonic
cerebral palsy that included their cervical muscles developed
accelerated spondylosis.

26. • Penning et al.13 believed that symptoms of
cord compression occurred when the
transverse area of the cord was <60 mm2
• Houser et al. thought that the shape and
degree of flattening of the spinal cord could
be an indicator of neurologic deficit; 98% of
their patients with severe stenosis and a
banana-shaped spinal cord had
clinicalevidence of myelopathy

27. • Ono et al. Described an anterior-posterior cord
compression ratio that was calculated by dividing
the anterior-posterior diameter of the cord by
the transverse diameter of the cord
• Patients with substantial flattening of the cord,
suggested by an anterior-posterior ratio of <0.40
tended to have worse neurologic function. Ogino
et al. Thought that an increase in this ratio to
≥0.40 or an increase in the transverse area to >40
mm2 was a strong predictor of recovery following
surgery

28. • Flexion and extension MRI images have shown
that increased stenosis is two times more
likely during extension than during flexion

29. Loss of the ventral disc interspace height which occurs
with the natural degenerative process results in loss of lordosis

30. • Retrolisthesis of a vertebral body can result in pinching
of the spinal cord between the inferior-posterior
margin of a vertebral body and the superior edge of
the lamina caudad to it .This compression may be
aggravated in extension, and it may be relieved in
flexion as the retrolisthesis tends to reduce.
• Forward slippage of a vertebral body may cause
compression of the spinal cord between the superior-posterior
margin of the vertebral body below and the
lamina above. This is aggravated by flexion

32. • spinal cord stretches with flexion of the
cervical spine and shortens and thickens with
extension
• Thickening of the cord in extension makes it
more susceptible to pressure from the
infolded ligamentum flavum or lamina
• In flexion, the stretched cord may be prone to
higher intrinsic pressure if it is abutting against
a disc or a vertebral body anteriorly

33. • cervical spondylosis will typically result in stiffening of
the spinal motion segments. It is not uncommon for
the motion segments one or two levels above the stiff
segments to become hypermobile. This is termed
“compensatory subluxation”
• cervical kyphosis is not uncommon in patients with
significant spondylotic changes. This deformity will
aggravate the degree of compression in patients with
cervical stenosis or disk herniations because the spinal
cord will be stretched over the posterior aspect of the
disks and vertebral bodies

34. Kyphosis associated with cervical spondylosis causes neural
injury, in part, by tethering the spinal cord over a ventral mass via
the “sagittal bowstring” effect (A). Dorsal decompression (i.e. via
laminectomy) may worsen deformation

35. Ossification of the posterior
longitudinal ligament (OPLL
• The ossification can be at one level, can involve skip-type
lesions at multiple levels, or can be a continuous
strip of bone
• The ossified ligament is often not a thin strip, but
rather a bulbous mass that may be centrally or
eccentrically located
• It can occur in conjunction with cervical spondylosis
and often produces severe anterior compression of the
spinal cord.
• Long-standing OPLL can ossify the adherent dura,
which may create the problem of spinal fluid fistulae

36. Ischemia
• degenerative elements compress blood vessels that supply
the cervical spinal cord and proximal nerve roots.
• Ischemia may result from direct compression of larger
vessels such as the anterior spinal artery and overall
reduced flow in the pial plexus as well as in small
penetrating arteries which supply the cord
• impairment of venous flow may lead to significant venous
congestion and contribute to spinal cord ischemia
• the region of the spinal cord most affected by CSM (levels
C5 to C7) is also the area with the most vulnerable vascular
supply

37. • Severe compression results in degenerative
changes in the spinal cord.
• The central gray matter and the lateral columns
show the most changes, with cystic cavitation,
gliosis, and demyelination most prominent
caudad to the site of compression. The posterior
columns and posterolateral tracts show wallerian
degeneration cephalad to the site of
compression. These irreversible changes may
explain why some patients do not recover
following decompressive surgery.

38. Cervical radiculopathy
• most common cause of cervical radiculopathy is a
foraminal constriction of multifactorial origin including
uncovertebral joint hypertrophy, facet arthropathy, and
loss of disk space height.
• the herniated disk is located posterolaterally,
compromising the nerve root at the entrance to the
neural foramen; occasionally the herniated disk is
centrally located and causes myelopathy. Cervical
nerves exit in the inferior aspect of the foramen; hence
the exiting, not the traversing, nerve is most likely to
be impacted by a disk herniation or a disk–osteophyte
complex.

40. Cervical Radiculopathy
• It is generally believed that only an inflamed
or irritated nerve root can result in radicular
pain on compression
• Chronic edema and fibrosis within the nerve
root
• mechanical compression of the dorsal root
ganglion

41. • Ferguson and Caplan divided cervical spondylotic
myelopathy into four syndromes
• (1) medial syndrome, consisting primarily of long-tract
symptoms;
• (2) lateral syndrome, consisting primarily of radicular
symptoms;
• 3) combined medial and lateral syndrome, which is the
most common clinical presentation;
• (4) vascular syndrome, which presents with a rapidly
progressive myelopathy and is thought to represent
vascular insufficiency of the cervical spinal cord.
Neurolneurol
clinics

42. Crandall and Batzdorf described five
broad categories of cervical
spondylotic myelopathy
• (1) transverse lesion syndrome, in which the corticospinal, spinothalamic,
and posterior cord tracts were involved with almost equal severity and
which was associated with the longest duration of symptoms, suggesting
that this categorymay be an end stage of the disease;
• (2) motor system syndrome, in which corticospinal tracts and anterior
horn cells were involved, resulting in spasticity;
• (3) central cord syndrome, in which motor and sensory deficits affected
the upper extremities more severely than thelower extremities
• (4) Brown-Séquard syndrome, which consisted of ipsilateral motor deficits
with contralateral sensory deficits and which appeared to be theleast
advanced form of the disease, and
• (5) brachialgia and cord syndrome,which consisted of radicular pain in the
upper extremity along with motor and/or sensory long-tract signs
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neurosurg

44. • Symptoms caused by cervical spondylosis can
be categorized broadly into three clinical
syndromes
• axial neck pain, cervical radiculopathy, and
cervical myelopathy

45. • Neck Pain
• Degenerative changes at the cervical disc and facet
joints
• The pain often stems from abnormalities in structures
innervated by the sinuvertebral nerve or branches of
the posterior primary ramus.
• Among the structures that the sinuvertebral nerve
innervates are the posterior longitudinal ligament, the
epidural vasculature, and the spinal periosteum
• Less commonly, the pain can be attributed to the facet
joints, which are innervated by the primary posterior
ramus

46. axial pain patterns
produced by injections into the facet
joints at the second through seventh
cervical level

47. source of neck pain
• Anterior neck pain along the
sternocleidomastoid muscle belly that is
aggravated by rotation to the contralateral side is
most often a result of muscular strain.
• Pain in the posterior neck muscles that is
worsened by flexion of the head suggests a
myofascial etiology.
• Pain in the posterior aspect of the neck that is
aggravated by extension, especially with rotation
of the head to one side, suggests the possibility
of a discogenic component.

48. Radicular pain
• symptoms are usually aggravated by extension or
lateral rotation of the head to the side of the pain
(the Spurling maneuver
• shoulder abduction sign.e., relief of severe
radicular pain when the patient rests the hand on
the top of the head
• decreasing tension within the nerve root, this
position may lift the sensory root DRG directly
cephalad or lateral to the source of compression,
and decompression of epidural veins may
contribute to pain relief

49. • Upper cervical radiculopathies occasionally
present as suboccipital pain with referral to
the back of the ear.
• C4 radiculopathy can present as neck and
shoulder pain with accompanying ipsilateral
diaphragmatic palsy

51. Radiologic Evaluation
• Typical radiographic manifestations include disk-space
narrowing, end-plate sclerosis, and osteophytic changes at
the end-plates, uncovertebral joints, and facet joints.
• Plain radiographs remain an important part of the
diagnostic workup, and anteroposterior (AP), lateral, and
flexion-extension views of the cervical spine should be
obtained in essentially all patients in this age group.
• Oblique views are useful for visualizing foraminal
narrowing, which is typically due to uncovertebral joint
spurs; however,. The AP view allows identification of
cervical ribs and scoliotic deformity. The lateral view is most
important, as it demonstrates the degree of disk narrowing,
the size of end-plate osteophytes, the size of the spinal
canal, and sagittal alignment

52. • In some cases, OPLL is visualized as a bar of
bone running along the posterior aspect of
the vertebral bodies.
• . Flexion-extension views are critical to
diagnose instability, which may not be evident
on a neutral lateral view.
• MR imaging provides optimal visualization of
soft tissues, CT-myelography offers better
definition of bone spurs and OPLL.

53. • Sensory conduction studies are useful in the
evaluation of a patient suspected
ofradiculopathy because SNAPs are typically
normal (because the lesion is rostral to the
DRG in the intervertebral foramina) even in
the face of clinical sensory loss, in contrast to
the situation in plexopathy and peripheral
nerve trunk lesions, where SNAPs are
attenuated or absent.

54. Needle EMG
• A study is considered positive if abnormalities—especially acute
changes of denervation including fibrillation potentials and positive
sharp waves—are present in two or more muscles that receive
innervation from the same root, preferably via different peripheral
nerves
• No abnormalities should be detected in muscles innervated by the
affected root's rostral and caudal neighbors.
• Reduced motor unit potential (MUP) recruitment and MUP
abnormalities of reinnervation (high-amplitude, increased
duration, polyphasic MUPs) are also sought.
• in the later phases of nerve root compression, the only needle
EMG changes indicative of radiculopathy might be chronic
neurogenic changes of reduced recruitment and MUP remodeling.
•

55. • Thank u