spondylolisthesis
TRANSCRIPT
Spondylolisthesis
TS Fong
12.3.2012
SPONDYLOLISTHESIS
Forward translation of one vertebra on another in the sagittal plane of the spine
Spondylolysis defect in the pars
interarticularis of lumbar vertebra
most commonly due to repeated and increased stress on the pars interarticularis
ANATOMY Pars
region between the superior and inferior articulating facet of the vertebra
weakest area in the neural arch susceptible to stress fracture
Pars defects not observed in newborns or nonambulatory
patients lysis or elongation does not occur in
primates that do not have an upright bipedal gait
presence of lumbar lordosis (unique in humans) is necessary for spondylolisthesis to occur
EMBRYOLOGY AND OSSIFICATION CENTRESSAGI ET AL SPINE 1998
pars ossify at 12-13 weeks gestation via endochondral ossification
Lumbar Vertebrae ossification centre in the region
of the pars uneven trabeculation and
cortication ossification centre that arises at
the upper end of pedicle uniform trabeculation throughout
the pars potential stress riser which could be
susceptible to fatigue fracture
CLASSIFICATION
CLASSIFICATIONWILTSE, NEWMAN AND MACNAB 1976
Type I: Dysplastic (child) Type II: Isthmic (5-50 yrs) Type III: Degenerative (older) Type IV: Traumatic Type V: Pathologic
DYSPLASTIC SPONDYLOLISTHESIS
dysplasia/aplasia of posterior facet joints of the L5/S1 levels
constant spina bifida occulta at the L5 level – congenital nature
concomitant elongation of the pars interarticularis --- frank lysis
condition is strongly familial, with as many as a third of first-degree relatives affected with the dysplastic form (Wynne-Davis et al)
Lateral radiograph
• rounding of the top of the sacrum as
L5 has rolled round anteriorly due to
poorly formed posterior facet joints
AP view
• 'Napoleon's hat' appearance of L5
superimposed through the sacrum
ISTHMIC SPONDYLOLISTHESIS
repetitive cyclical extension/torsion of the spine
repetitive infraction fatigue failure of the pars
high prevalence rate highest biomechanical forces on the pars
at L5/S1 level commonest site of a lytic spondylolysis
Lateral radiograph of a lytic
spondylolisthesis
Oblique radiograph of a lytic
spondylolisthesis
DEGENERATIVE SPONDYLOLISTHESIS
incompetence of the posterior facet joints 10x more common at the L4/5 than the
L5/S1 not encountered in the under 50-year-old the degree of slippage in the sagittal plane
is no good guide to the amount of neural compression
fourth dimension, time, is important degenerative process going on for years and years patients are much more readily able to adapt to
neural compression than for example with a rapidly growing tumour
CT scan
• level of a degenerative
spondylolisthesis
• facets have come forward to
contact the back of the
vertebral body and completely
close off the epidural space
DEGENERATIVE SPONDYLOLISTHESIS
Traumatic spondylolisthesis acute vertebral fractures do not occur
through the pars, but through pedicles, bodies, discs
so-called 'traumatic spondylolistheses' are not discrete entities
should not be part of the generic spondylolisthesis classification
Pathological spondylolisthesis metastasis and rheumatoid disease are the
more common causes disease of the whole motion segment rather
than the pars in particular
CLASSIFICATION MARCHETTI AND BARTOLOZZI 1997
etiology-based system importance of high and low grade developmental
spondylolisthesis permitting early recognition and treatment
LOW GRADE SPONDYLOLISTHESIS
low grade variety present in young adults frequently associated with spina bifida slip is characterized by translation without any
angulatory or kyphotic component
HIGH GRADE SPONDYLOLISTHESIS Usually at L5-S1 and become symptomatic in
adolescents wedge shaped L5 and a domed vertical sacrum anterior translation of L5 associated with angulation --
true lumbosacral kyphosis potential to develop into spondyloptosis if untreated or
mismanaged
CLASSIFICATION BY MARCHETTI AND BARTOLOZZI SPINE/SRS SPONDYLOLISTHESIS SUMMARY STATEMENT 2005
based on etiology clearly distinguishes between developmental
and acquired forms of this deformity highlights the pathogenesis of the different
types of spondylolisthesis potentially has the most relevance to natural
history, risk of progression, and implications for treatment
NATURAL HISTORY
wide spectrum of clinical presentation dysplastic and isthmic spondylolisthesis present
during childhood and adolescencedysplastic variety usually at a younger age than
isthmic early stages - low back pain is the only consistent
clinical feature immature patient - high index of suspicion should
be raised about the possibility of an underlying spondylolisthesis
NATURAL HISTORY hamstring tightness, spinal deformity, gait
abnormality frank neurology
severe degrees of spondylolisthesis usually dysplastic variety - lower lumbosacral
nerve roots can be compressed behind the upper back of the sacrum
isthmic spondylolisthesis some degree of L5 radicular pain is not
uncommon hypertrophic callus around the lysis
degenerative spondylolisthesis spinal claudication in association with low back
pain
PHALEN-DIXON SIGN
sciatic crisis typically seen in high grade adolescent spondylolisthesis
sign includes sciatic painvertical sacrum and pelvis lumbosacral kyphosistight hamstringshyperlordotic lumbar spine waddling gait
BACK PAIN AND SPONDYLOLISTHESIS
The cause of back pain is unclear and is multifactorial
The pain may be due to disc degenerationfacet degenerationchronic nerve root irritation from
compression or tractionpatient may have accompanying spinal
stenosis
RADIOGRAPHY
Defect in the pars interarticularis – ‘collar’ around the ‘neck’ of an illusory ‘dog’- oblique xray
THE BENDING FILMS
demonstrate persistent motion and instability
especially in the presence of degenerated disc disease at the level of spondylisthesis
disc degeneration and collapse of the disc space is an attempt to stabilize the motion segment
RADIOLOGICAL EXAMINATION large number of suggested and preferred radiological parameters
to assess spondylolisthesis Only 2 are of any great importance (Wiltse LL et al )
1. The amount of displacement2. The slip angle (the angular relationship between L5 and S1 in the
dysplastic form of spondylolisthesis)
Percentage slip (x/y(x 100)
slip angle or angle of sagittal rotation
RADIOGRAPHIC INDEX
Slip angle of Boxall
superior border is chosen more constant not affected by adaptive
changes commonly occur in the inferior end plate
represent local kyphosis across the L5-S1 motion segment
RADIOGRAPHIC INDEX the degree of slips or transitional displacement (Meyerding)
RADIOLOGICAL EXAMINATION
CT scan helpful in preoperative planning especially in cases
with severe dysplasia
MRI assess neural foramen on the sagittal views determine extent of associated disc disease disc herniation is common
25% cases occur at the level above the slip 15% occur at the level of the slip itself
rule out tumor or infection
MANAGEMENT
PREDICTORS OF SLIP PROGRESSION
female gender prepubescence trapezoidal L5 domed and vertical sacrum and
sagital rotation slip angle > -10o high grade slip (>50% slip
progression) inclined sacrum (>30o beyond
vertical)
INDICATIONS FOR SURGERY AGABEGI ET AL (THE SPINE JOURNAL 2010)
Slip progression more common in skeletally immature patients
who have not reached the adolescent growth spurt
the higher the grade of slip, the more likely it is to progress
slip progression rarely occurs in adults
High-grade slip with significant lumbosacral kyphotic deformity causing sagittal imbalance
INDICATIONS FOR SURGERY AGABEGI ET AL (THE SPINE JOURNAL 2010)
Neurological deficit In most cases, the L5 nerve root is involved
Low back pain unresponsive to a prolonged course of conservative treatment
Radicular pain with associated nerve root compression on imaging studies that is not responsive to conservative treatment
CONSERVATIVE TREATMENT
Directed at symptomatic relief Restanti-inflammatory agents lumbar corset
Physical therapy abdominal strengthening exerciseshamstring stretching avoidance of extension exercises which will
exacerbate the symptoms Sinaki et al showed 3-year outcomes were significantly better
in patients who followed the flexion exercise program compared to extension exercise
SURGICAL TREATMENT
directed towards symptoms and etiology radiculopathyneurologic deficit from spinal stenosis instability paindiscogenic pain
the mainstay of treatment is DecompressionFusion
Instrumented Non instrumented
ISTHMIC SPONDYLOLISTHESISTREATMENT VACCARO ET AL
Findings Treatmennt
Grade I observation
Grade II Asymptomatic: ObserveSymptomatic: Activity modificationFailed: Surgery
Grade III-IV Surgery
ISTHMIC SPONDYLOLISTHESISOPERATIVE TREATMENTprocedure advantage/disadvantage results
Defect repairs Preserve motionTechnically difficult
Variable 60-90%
Laminectomy (Gills) Increase instability Poor long term outcomeabandoned
Posterolateral fusion (in situ)
Improved symptoms ChildrenAdult: variable
Reduction and fusion Allow correctionAdd stability
Slippage >60%Slip angle >50 degreeAge 12 to 30(Bradford 1988)
Anterior and posterior fusion
Additional stability360 degree fusion
Difficult surgery
ROLE OF REDUCTION( AGABEGI ET AL, 2010 )
high-grade spondylolisthesis causes lumbosacral kyphosis --- sagittal imbalance
reduction procedure controversial literature support both sides of the argument
high rate of neurologic complications reserved for patients with loss of global
sagittal balance because of significant lumbosacral kyphosis
circumferential fusion and stable fixation with iliac screws are strongly recommended to prevent slip progression and pseudarthrosis
DEGENERATIVE SPONDYLOLISTHESISOPERATIVE TREATMENT OPTIONS
Decompressive laminectomy Decompression with posterolateral
fusion Decompression with instrumented
fusion
Long-term follow-up in patients with degenerative spondylolisthesis reveals a positive correlation between fusion and improved clinical outcome
THE FUSION OPTIONS
achieve posterior column stability posterolateral intertransverse fusion (PLF)
achieve anterior column stability anterior lumbar interbody fusion (ALIF)
achieving a circumferential fusion posterior lumbar interbody fusion (PLIF)transforaminal interbody fusion (TLIF)
no consensus of what constitutes optimal surgical treatment
surgical option must be individualized
POSTERIOR INTERTRANSVERSE FUSION
historically most popular way of performing fusion direct decompression of
the neural elements deformity correction stability with pedicle
screw instrumentation the disadvantages are
less optimal fusion rate: graft under tension
as it does not address the anterior column: persistent discogenic low back pain is common
ANTERIOR LUMBAR INTERBODY FUSION
allows for complete discectomy
permits placement of a large interbody graft facilitate slip angle correction reconstructs the disc space
height anterior graft
biomechanically compressive environment
allowing optimal fusion
ANTERIOR LUMBAR INTERBODY FUSION
The disadvantages related to the approach risk of injury to major vessels,
retroperitoneal and intraperitoneal structures
in males, the sympathetic plexus can be damaged and cause retrograde ejaculation
does not allow direct nerve roots decompression
Suk et al. anterior support would be helpful
for preventing reduction loss in cases of spondylolytic spondy- lolisthesis of the lumbar spine
CIRCUMFERENTIAL FUSION the benefits of anterior and
posterior surgery ( TLIF/PLIF) circumferential stability obviously
promotes high fusion rate Open or MIS
SPONDYLOPTOSIS
severe symptoms of low back pain, deformity, and neurologic symptoms or deficits
Surgical options in situ circumferential fusion technique
described by Smith and Bohlman Gaines procedure (resection of L5 and
reduction of L4 onto the sacrum through a combined anterior and posterior approach)
Gaines technique is associated with a high rate of postoperative neurologic deficits and is generally reserved for the most severe deformities
Gaines Procedure• resection of L5
and reduction of L4 onto the sacrum
• combined anterior and posterior approach
THANK YOU
Operative Vs Non-operative
multicenter, prospective study highest level of evidence guide decision-making on operative vs
nonoperative care for the specific disorder of degenerative spondylolisthesis
treatments compared were lumbar laminectomy with a single level fusion vs nonoperative treatment
treating surgeon determined type of fusion (uninstrumented posterolateral fusion, instrumented posterolateral fusion, circumferential fusion)
Conclusion patients with degenerative spondylolisthesis
and spinal stenosis treated surgically showed substantially greater improvement in pain and function during a period of 2 years than patients treated nonsurgically
DEGENERATIVE SPONDYLOLISTHESISOPERATIVE TREATMENT OPTIONS
Decompression alone or decompression with segmental arthrodesis ? higher proportion of patients with good or
excellent outcomes among patients who underwent decompression and arthrodesis compared with those underwent decompression alone (Herkowitz et al)
DEGENERATIVE SPONDYLOLISTHESISOPERATIVE TREATMENT OPTIONS
Instrumentation or non-instrumented fusion in degenerative spondylolisthesis
Martin et al ( systematic review )significantly higher rate of achieving a solid fusion in patients treated with instrumentation compared with those treated without instrumentation
Kornblum et al solid arthrodesis is associated with less segmental instability and better outcomes than pseudarthrosis
supports the use of instrumentation for fusion rates