4. INTERVERTEBRAL DISC
Hydrostatic, load bearing structure between the
vertebral bodies from C2-3 to L5-S1 .
Twenty-three discs span the vertebral column
between C2 and S1.(6 cervical, 12 thoracic and 5
lumbar )
Nucleus pulposus + annulus fibrosus
No blood supply
L4-5, largest avascular structure in the body
5. INTERVERTEBRAL DISC
•Type II collagen strand + hydrophilic
proteoglycan
•Water content 70 ~ 90%
•Confine fluid within the annulus
•Convert load into tensile strain on the annular
fibers and vertebral end-plate
Nucleus Pulposus
6. ANNULUS FIBROSUS
Outer boundary of the disc
More than 60 distinct, concentric layer of
overlapping lamellae of type I collagen
Fibers are oriented 30-degree angle to the disc
space
Helicoid pattern
Resist tensile, torsional, and radial stress
Attached to the cartilaginous and bony end-plate at
the periphery of the vertebra
7. Anterior annulus is almost straight whereas
posterior margins have a physiological bulge
which increases with extension and
straightens with flexion
Peripheral fibres of annulus insert above and
below the apophyseal bony rings(vertebral
end plates) in to the periosteum of the
vertebra
ANNULUS FIBROSUS
8. •Cartilaginous and osseous component
•Nutritional support for the nucleus
•Passive diffusion
VERTEBRAL END-PLATE
9. INNERVATION
Outer 1/3 of anulus
and PLL innervated
by sinuvertebral
nerves
Anterior disc has
some sensory input
through sympathetic
trunk
Posterior spinal
elements carry
nociception through
medial branch
nerves
The lumbar disc is supplied by a network of pain
fibers from the sympathetic chain arising from the
sinuvertebral nerve, which innervates the outer six
11. PHYSIOLOGY OF DISC
Disc able to support weight because it contains
proteoglycans
Substantial osmotic gradient between disc and
plasma
Resulting force favouring flow of water into
disc opposed by compressive force of upright
posture
Two opposing forces reach a balance point
based on position
Water flows into the disc in supine posture and
12.
13. INTERVERTEBRAL DISC HERNIATION
Is a medical condition affecting the spine in
which a tear in the outer, fibrous ring
(annulus fibrosus) of an intervertebral disc
allows the soft, central portion (nucleus
pulposus) to bulge out beyond the
damaged outer rings.
14. BURDEN OF THE PROBLEM
60-90% life time incidence of
backache
The incidence 5 to 20 cases per
1000 adults annually
1-3 percent of patients symptomatic
.
95 % chance of herniated discs
occurring either at L4-L5 or L5-S1
Peak in 40’s (third to the fifth decade
)
Male to female ratio of 2:1
15. ETIOLOGY
There is a higher rate of disc
herniation in the lumbar and
cervical spine due to the
biomechanical forces in the
flexible part of the spine.
Other causes
• Connective tissue disorders
• congenital disorders such as
short pedicles.
Trauma - second
most common
cause . The most common cause -
degenerative process in
which, as humans age, the
nucleus pulposus becomes
less hydrated and weakens.
This process will lead to a
progressive disc herniation
that can cause symptoms.
16. RISK FACTORS
Repetitive mechanical activities
Living a sedentary lifestyle
Traumatic injury to lumbar discs commonly
occurs when lifting while bent at the waist
Obesity – degeneration quickens
Practicing poor posture
Tobacco abuse – The chemicals commonly
found in cigarettes can interfere with the
disc’s ability to absorb nutrients
24. DISCOGENIC PAIN
Sciatica has been known since antiquity, but the
relationship between sciatica and disc herniation
was not discovered until the beginning of the
20th century.
In 1934,Mixter and Barr were the first to describe
this correlation
Discogenic pain is classically associated with sitting
intolerance and flexion of the spine
Symptoms vary depending on the location of the herniation
and the types of soft tissue that become involved.
25. LOCATION
The majority of spinal disc herniation cases
occur in lumbar region (95% in L4-L5 or L5-
S1).
The second most common site is the cervical
region (C5-C6, C6-C7).
The thoracic region accounts for only 0.15%
to 4.0% of cases.
Symptoms vary depending on the location of
the herniation and the types of soft tissue
that become involved.
26. SYMPTOMS
Axial Back Pain
Radicular Pain - The cardinal symptoms of lumbar disc
herniation are radicular leg pain with or without a
sensory loss (dermatomal)and motor deficit
Difficulties stooping and picking up things
Restriction in running and jumping
Diminished stride
Cauda equina syndrome (massive herniation) which
is characterized by:
Incapacitating back and leg pain
Numbness and weakness of the lower extremities (saddle
anaesthesia)
Bladder bowel incontinence
Paralysis of affected nerve distribution(below the
dermatome in thoracic)
28. SYMPTOMS
Axial Back Pain from Intervertebral Disc
Disease (without Deformity)
The most classic disc-related mechanical pain
syndromes present
as pain that worsens with activity and lessens
with rest.
Anterior thigh pain can also be associated with low
back pain, as the symptoms may follow a
somatotopic pattern.
29. Radicular Pain
Sharp, shooting pain in a given dermatome, but
it may be dull or aching as well
Patients may report an abrupt onset of
symptoms with acute anular tears, which
typically occur while the person is bent over to
lift, and are described as a “pop” in the spine
followed by severe pain.
Activities that increase intradiscal pressure
(e.g., coughing, sneezing, and bending forward)
or increase axial loading (e.g., running) can
SYMPTOMS
32. CLINICAL EVALUATION
Goals
Localisation
Differentiate between mechanical,
neuropathic and non-neurological pain
• Mode of onset
• Character
• Distribution
• Associated motor, sensory symptoms
• Bladder and bowel control
• Exacerbating and remitting factors
• History of predisposing factors
• ( cancer, osteoporosis)
History
33. HISTORY
Three major concerns:
Is there evidence of systemic disease
Is there evidence of neurological disease
Is there social or psychological stress which
is contributing?
Exclude serious underlying pathology, such
as infection, malignancy or cauda equina
syndrome (RED FLAGS)
40. PIRIFORMIS SYNDROME
Pain from piriformis
muscle – irritation of
sciatic nerve passing
deep or through it
Pain on resisted
abduction / external
rotation of leg
41. IMAGING MODALITIES
Xrays good first line Ix if red flags,
osteoporotic fracture
CT Scan bone tumours fractures and spinal
stenosis
MRI spinal cord, nerve roots, discs,
haemorrhage
Myelography
42. RADIOGRAPHS (X RAYS)
Shows bones only
Helpful in older patients where cause of stenosis is likely
to be a result of degenerative changes or listhesis
If spondylolisthesis is present, need flexion and
extension views to evaluate for segmental instability
Scoliosis evaluation may be beneficial in some cases
43. MRI
Provides the best anatomic
picture and allows focus on
soft tissue
Needs to correlate with
physical examination
Many findings on MRI can
be asymptomatic
High-field better than Open,
need complete study
44. Anatomical classification MRI BASED
Herniation
Protrusion
extrusion
Migration-
displacement of disc
material away from
the site of extrusion,
regardless of
whether
sequestrated or not
Sequestration-
Extrusion may be
further specified as
sequestration, if the
displaced disc
material has lost
completely any
continuity with the
parent disc
Herniation- localized displacement of disc
• >50% (180º) = bulge
• <50% = herniation
46. Location Classification
central prolapse
• may present with cauda equina syndrome which
is a surgical emergency
posterolateral (paracentral)
• most common (90-95%)
• PLL is weakest here
foraminal (far lateral, extraforaminal)
• less common (5-10%)
axillary
• can affect both exiting and descending nerve roots
47.
48. MYELOGRAM
Study of choice
when MRI can not
be done
Frequently an
uncomfortable
procedure
Post-myelogram CT
can give additional
information about
canal contents
49. CAVEATS OF MANAGEMENT
Adequate/complete
initial evaluation
Follow-up evaluations
1-3 days for acute pain
4-6 weeks for chronic
pain
Activity Activity Activity
Survey for Red Flags
50. MANAGEMENT OPTIONS
Non-operative management
Bed rest
Physiotherapy –
In the acute phase: Use of hotpacks, short wave
diathermy, • microwave therapy.
After the acute phase: graduated regime of back
•exercises is instituted
Use of lumbar corset whenever the patient is
active
NSAIDs
Muscle relaxants
Epidural corticosteroid injections
51. NON OPERATIVE TREATMENT
Short-term rest (recommended 2
weeks)
**Conservative treatment should
continue for 6weeks, before other
measures are attempted
57. INDICATIONS FOR SURGERY
Ideal candidate
History, physical examination, radiographic finding, are
consistent with one another
Root tension sign (+)
When discrepancy exist, the clinical picture should serve as the
principal guide.
Absolute surgical indications
Definitive evidence for nerve root compression/myelopathy
(cervical disc)
Cauda equina syndrome
Severe paresis
Paraparesis/paraplegia (thoracic disc herniation)
Relative indication
Progressive weakness
No response to conservative treatment > 6 weeks
63. LUMBAR FUSION
lumbar fusion is
only indicated for
recurrent lumbar
disc herniations,
not primary
herniations
64. CHEMONUCLEOLYSIS
Intradiscal injection of chymopapain which
causes hydrolysis of he cementing protein of
the nucleus pulposus.
This causes decrease in water binding
capacity leading to reduction in size and
drying the disc.
67. OUTCOME OF SPINAL SURGERY
•Non-Smoker/Normal BMI patients: 77 percent
• Normal BMI - all patients: 74 percent
• Obese with a BMI greater than 30: 59 percent
• Active Smokers: 58 percent
• Obese and litigator: 53 percent
• Obese, active smoker and litigator: 41
percent