2. Spondylolisthesis
Definition
The term "Spondylolisthesis" refers to a condition where
one of the vertebrae (usually L5) becomes misaligned
anteriorly (slips forward) in relation to the vertebra below.
This forward slippage is caused by a problem or defect
within the pars interarticularis. Occasionally, facet joint
and/or posterior neural arch defects may also cause this
syndrome as well.
The forward slippage does NOT always occur. This non
slipped pars defect is called a "Spondylolysis" and is
almost always a precursor to the actual forward slippage.
5. Classification
Dysplastic spondylolisthesis
Isthmic spondylolisthesis
DEGENERATIVE SPONDYLOLISTHESIS
TRAUMATIC SPONDYLOLISTHESIS
PATHOLOGICAL SPONDYLOLISTHESIS
IATROGENIC SPONDYLOLISTHESIS
Meyerding’s Classification
• Grade I : Slip from 0-25% up to 1/4 length
• Grade II : Slip from 25-50% up to 1/2 length
• Grade III : Slip from 50-75% up to 3/4 length
• Grade IV : Slip more than 75% up to 3/4 length
6. Dysplastic spondylolisthesis
Is a true congenital spondylolisthesis that occurs because
of malformation of the lumbosacral junction with small,
incompetent facet joints.
Very rare, but tends to progress rapidly
Often associated with more severe neurological deficits.
7. Isthmic spondylolisthesis
SUB-TYPE A:
Is the most commonly found type of
spondylolisthesis in people under 50 years
of age.
It is believed that "biomechanical stress,"
such as repetitive mechanical strain from
heavy work or sports, causes a fatigue
fracture within the pars interarticularis.
8. Isthmic spondylolisthesis
SUB-TYPE B:
• This type of Isthmic spondylolisthesis is characterized by a
elongated pars without separation.
• It is believed that the elongation occurs secondary to "repeated,
minor trabecular stress fractures of the pars." Each time these
possible sub-acute stress fractures occur and heal, the vertebral
body is displaced farther and farther forward. Eventually, the pars
may fail to heal and result as a full pars defect.
SUB-TYPE C:
These types of spondylolisthesis' are extremely rare and result
from an acute pars fracture, often as result of traumatic lumbar
hyperextension injury
9. DEGENERATIVE SPONDYLOLISTHESIS
o This is the most common form of spondylolisthesis
in patients over 50 years of age and rarely occurs in
those under 50
o There is no fracture or elongation of the pars
interarticularis and the neural arch is intact. In
contrast, patients with isthmic spondyolisthesis
almost universally have widening of the central
spinal canal at the level of the slip. This narrowing
of the canal in degenerative spondylolisthesis has
been termed the "napkin ring effect.
10. DEGENERATIVE
SPONDYLOLISTHESIS
• The classic symptomology of patients with symptomatic
degenerative spondylolisthesis are similar to those with
symptomatic lumbar spinal stenosis; which can be either
neurogenic claudication or radiculopathy (either unilateral
or bilateral radiculopathy) with or without low back pain.
• Neurogenic claudication is thought to result from central
canal narrowing that is exacerbated by the listhesis
(forward slip). The classic symptoms of neurogenic
claudication are bilateral (both legs) posterior leg pain that
worsens with activity, but is relieved by sitting or forward
bending.
11. TRAUMATIC SPONDYLOLISTHESIS
This type of spondylolisthesis, which is
extremely rare, results from a
traumatically-induced fracture to the
neural arch other than the pars region.
One of the examples is The "Hangman's
Fracture" in the cervical spine's second
vertebra (Axis) is a common and often
deadly example of such a traumatically
induced phenomenon. This type of fracture
is extremely rare in the lumbar spine.
12. PATHOLOGICAL SPONDYLOLISTHESIS
Generalized or systemic disorders of bone may
affect the neural arch of the spine and allow
spondylolysis or spondylolisthesis to occur.
– Osteoperosis
– Paget's disease
– Metastatic carcinoma
13. IATROGENIC SPONDYLOLISTHESIS
:
Is a complication of lumbar anterior interbody fusion
(LAIF). Either the vertebrae above o below develops a
pars fracture.
Laminectomy procedures will result in an overload of
weight-bearing stress on the contralateral pars and, in
some patients, result in a pars fracture.
14. symptoms
Spondylolysis commonly is asymptomatic
Symptomatic patients often have pain with
extension and/or rotation of the lumbar spine
Common nerve symptoms
15. symptoms
Leg pain
Electric shock-like symptoms traveling down the
leg
Numbness or tingling in the legs and feet
Muscle weakness of the legs
Other symptoms can occur. bowel or bladder
dysfunction, or any numbness around the genitals,
These symptoms may be a sign of cauda equina
syndrome.
16. DIAGNOSIS
• MRI of the lumbar spine can easily identify acute stress reactions
in the pars interarticularis. However, direct identification of pars
defects (old stress) may be slightly more difficult with MRI than
with CT.
• BONE SCAN : easily identifies acute stress reaction in the pars
interarticularis, but cannot identify old pars defect.
17. Treatment
o If the slip is small and the symptoms are
manageable, then treatment is most often with
observation. In children, this may include activity
restrictions, such as participation in some sports.
o When the slip is more significant, there may be a
higher risk of the problem progressing, and
surgery may be favored. In addition, patients who
have symptoms of nerve compression are more
likely to have surgery recommended.
