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

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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