Spondylolisthesis

BPT
Clinical Orthopedics Lecture 2022

1. Spondylolisthesis
Dr Dibyendunarayan Bid PT, Ph.D.
Sarvajanik College of Physiotherapy, Surat

2. •‘Spondylolisthesis’means
forwardtranslationofone
segmentofthespineupon
another.
•Theshiftisnearlyalways:
•betweenL4andL5,or
•betweenL5andthesacrum
•11%occuratL4/5and
•82%occuratL5/S1.

3. •Normaldiscs,laminaeandfacetsconstitutealocking
mechanismthatpreventseachvertebrafrommoving
forwardsontheonebelow.
•Forwardshift(orslip)occursonlywhenthismechanism
hasfailed.
•Causesofspondylolisthesisaremultifactorialbuta
largeproportionaredegenerative.

4. Classification
•The Wiltse-Newman classification
of Spondylolisthesis is most
commonly used.
I Dysplastic
II Isthmic
IIA Disruption of pars as a
result of stress fracture
IIB Elongation of pars
without disruption related to
repeated, healed
microfractures
IIC Acute fracture through
pars
III Degenerative
IV Traumatic
V Pathologic
VI Iatrogenic

5. •The first two types present in childhood and adolescence.
•TypeVI(iatrogenic)isnotpartoftheoriginalWiltse-
Newmanclassificationbut,withinjudiciousfacetectomyand
parsfractureduringlaminectomies,iatrogenicinstabilitycan
occur.

6. •Dysplastic (4–8% incidence but accounts for 20% of all
spondylolisthesis)
•Type I includes congenital abnormalities of the lumbosacral junction.
•The superior sacral facets are deficient or malorientatedand the
sacrum is dome-shaped or hypoplastic.
•The pars may be poorly developed. Slow and relentless forward slip
leads to severe displacement.
•Associated anomalies (usually spina bifida occulta) are common.

7. •Lytic or isthmic (5% incidence)
•In type II, the commonest variety, there are defects in the
pars interarticularis (spondylolysis), or repeated breaking
and healing may lead to elongation of the pars.
•The defect (which occurs in about 6% of people) is usually
presentby the age of 7, but the slip may appear only some
years later.
•Itisdifficulttoexcludeageneticfactorbecause
spondylolisthesisoftenrunsinfamilies,andismorecommon
incertainraces,notablyEskimos;
•Buttheincidenceincreaseswithageuptothelateteenageyears,
althoughclinicalpresentationwithpaincancontinueintolatemiddle
age.

8. •TypeIIAismorecommonandisessentiallyastress
fracturefromrepetitiveloadingespeciallyincompetitive
athletes(11%incidenceinfemalegymnastsand21%incollegefootball
players).
•This results in a radiolucent defect in the pars (non-union).
•Type IIB is characterized by repeated microfractures which
heal with pars elongation and is occasionally confused with
dysplastic type.
•Type IIC is a pars fracture caused by an acute injury.

9. •Spondylolysis has a benign course.
•Thegeneralincidenceof6%doesnotchangewith
increasingagefrom20to80yearsandtheoverwhelming
majorityofcasesareasymptomatic.
•Onlyabout4%ofparsdefectstendtoprogressto
significantslipsofmorethan20%overseveralyears.

10. •Degenerative (25% incidence)
•Degenerative(typeIII)changesinthediscandfacetjoint
incompetencepermitforwardslip(nearlyalwaysatL4/5and
mainlyinwomenofmiddleage).
•L4-L5facetshaveasagittalorientationwhichallowsforward
slippage(asopposedtotheL5/S1jointswhicharehavea
coronalorientation).
•Degenerativespondylolisthesisiscommonlyseenabovea
sacralizedL5vertebraduetoincreasedmechanicalstresses.
•These slips rarely progress more than 30% of the body width.

11. •Post-traumatic
•Posterior arch fractures (not including the pars)may result in
destabilization of the lumbar spine and allow vertebral
slip.
•Pathological
•Bone destruction (e.g. due to tuberculosis or neoplasm)
may lead to vertebral slipping.

12. •Iatrogenic
•IatrogenicisnotpartoftheoriginalWiltse-Newman
classificationbut,withinjudiciousfacetectomyandpars
fractureduringdecompression,iatrogenicinstabilitycan
occurleadingtospondylolisthesis.

13. Pathology
•Type I dysplastic spondylolisthesis will progress in
32% of cases.
•Theyaremorelikelytobecomehigh-gradeslipswith
significantchanceofneurologicalinjuryandmore
commonlyrequiresurgery.
•Anterior vertebral translation results in a sagittal
deformity with compensatory pelvic rotation.
•This results in a vertical sacrum and loss of lumbar
lordosis.

14. •With forward slipping there is compression on the cauda
equina and the exiting foraminal nerve roots (L5).
•The degree of slip is measured by the amount of overlap of
vertebral bodies and is expressed as a percentage.
•High-grade slips have more than 50% translation.

15. •With Type II pars isthmic stress fractures, healing can occur with
immobilization especially with unilateral defects.
•Whennon-unionoccurs,thefracturebecomescorticalizedandfilledwith
fibroustissue.
•A ‘lytic’ defect is visible on X-ray.
•Thelossoftheposteriorfacetsupportresultsinincreaseddiscloadswith
subsequentdegenerationandasmallriskofspondylolisthesis(4%).

16. •TypeIIIischaracterizedbysegmental‘instability’dueto
discorfacetincompetencewithosteophytesandfacet
effusions.
•Lateralrecessstenosisoccursduetofacetosteophytes
andligamentumflavumhypertrophywhichencroacheson
thetraversingnerveroots.
•Occasionally there is foraminal stenosis which compresses
the exiting nerve root.

17. Clinical features
•Typically a child or adolescent with spondylolysis presents with
low back pain or pain that radiates to the buttock or posterior
thighs.
•Onset is usually insidious and related to sporting activities;
occasionally an acute injury may precipitate events.
•Neurological deficit is rare.
•There is a slightly higher incidence of spondylolysis in idiopathic
scoliosis.

18. •Withadysplasticspondylolisthesis,thechildmay
havetypicalflatbuttocks,averticallyorientedsacrum
andalumbosacralsteppalpable.
•Hamstringtightnessiscommonandmayresultinflexed
hipsandknees.
•Neurologicalexaminationmayrevealnerveroottension
signs(commonlyL5root).

19. •Degenerative spondylolistheses presents in
middle age with chronic lower back pain, spinal
stenosis or radicular pain (Figure 18.37).
•Walking distance is restricted and symptoms are
relieved by forward flexion.

20. Figure 18.37
Spondylolisthesis –clinical
appearance
The transverse loin
creases, forward tilting of
the pelvis and flattening of
the lumbar spine are
characteristic.

21. X-rays
•Oblique films may demonstrate the classic ‘Scotty dog neck’ which is
pathognomonic of a pars fracture with a broken neck or collar.
•About 20% of pars defects are only shown on oblique films.
•Lateralviewsshowtheforwardshift(spondylolisthesis)oftheupper
partofthespinalcolumnonthestablevertebrabelow(Figure
18.38);elongationofthearchordefectivefacetsmaybeseen.

23. •When there is no gap, the pars interarticularis is elongated or
the facets are defective.
•Thedegreeofslipismeasuredbytheamountofoverlapof
adjacentvertebralbodiesandisusuallyexpressedasa
percentage.

24. Prognosis
•Dysplasticspondylolisthesisappearsatanearlyage,
oftengoesontoasevereslipandcarriesasignificant
riskofneurologicalcomplications.
•Ifprogressionispredicted,earlysurgeryis
recommended.

25. •Lytic(isthmic)spondylolisthesiswithlessthan10%
displacementdoesnotprogressafteradulthood,but
itmaypredisposethepatienttolaterbackproblems.
•Itisnotacontraindicationtostrenuousworkunless
severepainsupervenes.
•With slips of more than 25% there is an increased risk of
backache in later life.

26. •Degenerativespondylolisthesisisuncommon
beforetheageof50,progressesslowlyand
seldomexceeds30%.

27. Treatment
•Conservative treatment, similar to that for other types of back pain, is
suitable for most patients and is based on symptom management.
•Short-term bed rest, activity restriction, pain medication, NSAIDs, muscle
relaxants, steroid injections, physical therapy and bracing are all common
treatment modalities.
•Operative treatment is indicated if:
(1) the symptoms are disabling and interfere significantly with
work and recreational activities (loss of ADL);
(2) the slip is more than 50% and progressing;
(3) neurological compression is significant.

28. •CHILDREN
•Indysplasticspondylolisthesis,thereiscommonly
progressiontohighgradeslips(>50%translation)at
L5/S1andthechildpresentswithlowerbackpain,
hamstringtightnessandsciatica.
•Surgical treatment is fusion of the dysplastic listhesed
segment.
•Some controversy exists over the need for reduction of
the slip, the extent of reduction and the surgical
technique.

29. •Historically,posterolateralinsitu(initsoriginalplace)fusionhasbeen
theprocedureofchoiceforpaediatricspondylolisthesis.
•However,forhigh-gradespondylolisthesis,thesmalltransverse
processesresultinahighpseudarthrosisrateandsagittal
balanceisnotaddressed.
•Instrumentedreductionandcircumferentialfusionimproves
fusionratesandtheposture,butthesurgeryistechnically
demandingandhasahighercomplicationrate.

30. •Spondylolysis
•The mainstay of conservative management is activity
restriction.
•NSAIDs are used for analgesia as required.
•Thepain-producingsportingactivitiesneedtobe
restrictedandactivecompetitionstoppedfor4-12
weeks.
•Bracing is controversial with no consensus.

31. •With failed conservative treatment after 9-12 months,
surgery is indicated.
•Posterior uninstrumentedfusionis the default procedure
but thissacrifices a motion segment.

32. •Wherethereisnodiscdegenerationor
spondylolisthesisinayoungpatient(<20),parsrepairis
possible,butthepainshouldbeisolatedtothelysis,
whichcanbeconfirmedwithlocalanaesthetic
injections.
•When there are relative contraindications to pars repair,
posterior fusion remains the gold standard.

34. •Degenerative spondylolisthesis
•Mostpatientsrespondtoconservativetreatmentbut
10-15%ofpatientswithdegenerativespondylolisthesis
willrequiresurgeryforlowerbackpain,spinalstenosis
and/orradiculopathy.
•Progressiveweakness,caudaequinasymptomsand
lossofactivitiesofdailyliving(ADLs)withpoorquality
oflifeareindicationsforsurgery.

35. •Whensymptomsaremainlythoseofspinal
claudication,decompressionaloneissuccessful.
•However,mechanicalbackpain,abnormalmotionon
dynamicX-raysandlargefaceteffusionsonMRIare
featureswhichmayrequirefusioninadditionto
decompression.
•Posterolateral fusion is the standard, and pedicle screw
instrumentation produces higher fusion rates.

36. •Modern segmentalpediclescrewfixationallows
spondylolisthesisreductionandrestorationofforaminalheight
fornerverootdecompression.
•Posteriorinstrumentationmaybeaugmentedwithanterior
interbodyfusion(circumferentialfusion)eitherfromposterioror
aseparateanteriorapproach.
•Thisallowsimprovedlordosiscorrectionandfusionrates
(especiallyinsmokers).

37. Ref:
•Apley’sOrthopedics