This document provides information about spondylolisthesis, including its anatomy, classification, presentation, diagnosis, and treatment. It defines spondylolisthesis as the slipping of one vertebra over another, most commonly between L4-L5 or L5-S1. It is classified into 5 types including dysplastic, isthmic, degenerative, traumatic, and pathological. Clinical presentation varies from being asymptomatic to back pain and sciatica. Diagnosis involves imaging like x-rays, CT, and MRI. Treatment ranges from conservative options like bracing and exercises to surgical options like decompression and fusion when conservative treatments fail.

1. SPONDYLOLISTHESIS
PROF. (DR.) MD. SHAH ALAM
MBBS, MS, FCPS, FRCS
Fellowship Training in Spine Surgery (USA)
Imperial Spine Course (UK)
Professor
Department of Ortho & Spine Surgery
National Institute of Traumatology & Orthopaedic Rehabilitation (NITOR)
Dhaka, Bangladesh

2. Introduction
 First reported by belgian obstetrician in 1782 as a narrowed
birth canal.
 It was caused by displacement of fifth lumber vertebra over
the sacrum
 Spondylolisthesis is defined as anterior or posterior slipping
displacement) of one segment of the spine on the adjacent
segment.
 Shift is nearly always between L4 and L5 or L5 and S1.

3. Anatomy
 Pars
 Region between the superior and
inferior articulating facet of the vertebra
 weakest area in the neural arch
 susceptible to stress fracture
 Spondylolysis is a unilateral or bilateral
defect of the pars interarticularis.

4.  Normally laminae and facets constitute a
locking mechanism which prevents each
vertebra from moving forwards on the one
below.
 So, when there is a failure of this mechanism
this forward or backward shift or slip occurs.

5. Hook and catch concept
Hook:
 Pedicle
 Pars inter-articularis
 Inferior process of the cephalad level
Catch:
 Superior process of the caudal level

6. Epidemiology &Etiology
 The incidence: 5- 8%
 The degenerative spondylolisthesis rarely before 40
years, and is four to five times more common in women
than in men.
 It increases with age and repeated stress eg. gymnasts
and weightlifters.
 May be congenital or acquired
 There is no proven single etiology

7. Prevalence and localization
 Higher prevalence in atheletes about 27%-47%(javelin)
 High percentages found in patients with scheurmann’s
disease
 80% spondylolisthesisis asymptomatic.
 If symptomatic 80% can be treated conservatively.
 Only 15-20 % requires surgical treatment.

8. Grading
Grading was done by meyerding on the basis of
amount of vertebral slipage.

10.  The slip angle is the best predictor of instability or
progression of the spondylolisthesis deformity,
 Restoration of spinopelvic balance is important in the
treatment of spondylolisthesis.
 The normal slip angle in a patient without
spondylolisthesis should be lordotic.
 Normal slip angle is 0-100.

11.  The slip angle, which is formed by the intersection of a line
drawn parallel to the inferior or superior aspect of the L5
vertebra and a line drawn perpendicular to the posterior aspect
of the body of the S1 vertebra

12. Pelvic parameters
 Position of pelvis plays important role in upright
sitting and standing postures
 Pelvic parameters consist of
 Pelvic Incidence (PI)
 Pelvic Tilt (PT)
 Sacral Slope (SS)

13. Pelvic Incidence
 Angle between line from femoral head(s) to midpoint of sacrum
and line perpendicular to superior endplate of sacrum
 This is a morphologic parameter – how much sacrum is angled in
a person.
 Basically, it describes the shape of the sacrum that we are born
with
 Stays constant throughout life
except for slight change in puberty
Average PI= 550 ± 100

14. Pelvic Tilt
 Angle between a line from midpoint of femoral heads to center
of superior endplate of sacrum and a vertical line to midpoint of
femoral heads
 This is a positional parameter, meaning that unlike the PI, it
can change
 Ideally PT < 200
 Increased PT after surgery implies
residual postoperative spinal deformity
and negative effect to function &
outcome (highly correlated with outcomes)

15. Sacral Slope
 Angle between line drawn
along superior endplate of S1
and a horizontal reference
line
 PI = PT + SS
 As PT increases, SS
decreases (pelvic
retroversion)

16. PI = PT + SS

17. Classification and grading
Classification system was given by wiltse and co-workers in 1976.
 1.Dysplastic 20%
 2.Isthmic form 50%
-Lytic
-Elongation without lysis,
-Acute traumatic form
 3.Degenerative form {pseudospondylolisthesis}-25%
 4.Traumatic form {pedicle, lamina,facet joint}
 5.Pathological
 6.Iatrogenic

19. Type I: Dysplastic spondylolisthesis
– Occurs only at L5-S1 level
– Typically the inferior facet of L5 is dysplastic and the
sacral facet absent.
– No pars interarticularis defect
– Frequent assosciation with spina bifida occulta of L5
and sacrum.
– More common in females.
– Increased incidence in first degree relatives of patients:
genetic
 can lead to a slip of more than 50%.

20. Type II: Isthmic spondylolisthesis
 Most common type
 Caused by the development of a stress fracture of the
pars interarticularis.
 Commonest form is lytic & isthmic variety.
 Repeated breaking & healing may lead to elongation of
the pars .
 This defect may be in 5% people at the age of 7 years.
But slip starts to appear few years later.
 There is genetical co-relation because it runs in families
and races eg. Eskimos.

21. Type III: Degenerative spondylolisthesis
 Usually women over 50 yrs. M:F= 1:4-6
 Most common at L4-5
 Many patients have generalized OA and pyrophosphate
crystal arthropathy
 Does not progress beyond 30 percent.
 Often accompanied by spinal stenosis,

22. Type IV: Traumatic spondylolisthesis
 Caused by fracture or dislocation of the lumbar spine, not
involving the pars.
Type V: Pathologic spondylolisthesis
Bone destruction may be due to infection( TB) or neoplasm. Others
–rheumatoid arthritis, paget’s disease, osteogenesis imperfecta.
Is a condition where the entire L5 vertebra translates past the
anterior edge of the sacrum, there by falling off the sacrum.
SPONDYLOPTOSIS

23.  Common variety i.e lytic type-
 Pars interarticularisis in two pieces(spondylolysis) and
the gap is occupied by fibrous tissue.
 With repeated stress vertebral body & superior facets in
front of gap may subluaxateor dislocate forwards
Pathology

24.  When there is no gap the pars interarticularisis elongated
or the facets are defective.
 Due to this forward slip there may be pressure on the
duramatter and caudaequina or on the emerging nerve
root.
 Sometimes disc prolapse may occur.
Pathology

25. Risk factors for slip progression
(Hensinger 1989)
 Clinical
 Growth yrs (9 – 15)
 Girls > boys
 Back pain
 Postural or gait abnormality
Radiographic
Type 1 (dysplastic)
Vertical sacrum
>50 % slip
Increasing slip angle
Instability on flex/ext views

26. Clinical presentation (Symptoms)
 In children -usually painless but the mother may
notice the unduly protruding abdomen and peculiar
stance.
 F/O nerve root compression usually absent.
 Tight hamstring may be only findings.
 Pelvic waddling gait.

27.  The patient is usually asymptomatic.
 Low back pain (most common), and is exacerbated
by motion, may relieved by rest.
 Sciatica in one or both leg.
 F/O nerve root compression.
 palpable step may be found.

28. Clinical presentation (Signs)
 Muscle tightness (tight hamstrings muscle) that is
associated with all grades of spondylolisthesis occurs at
a rate of 80%.
 Buttock- flat, heart shaped.
 Lumber spine look too short.
 Sacrum looks vertical.

29. Clinical presentation (Signs)
 Paraspinal muscle spasm and tenderness are usually
present.
 Back pain on lumber hyperextension.
 Limited forward flexion of the trunk is common with
reduced straight-leg raising
 Postural deformity and a transverse abdominal crease.

30. Phalen-Dixon sign
 sciatic crisis typically seen in high
grade adolescent spondylolisthesis
 sign includes
 sciatic pain
 vertical sacrum and pelvis
 lumbosacral kyphosis
 tight hamstrings
 hyperlordotic lumbar spine
 waddling gait

31. Diagnostic Imaging
 X-ray
1.Oblique view
2.Lateral view should be taken in standing because
a 26% increase in slipping has been noted standing
films than lying film.
3.Dynamic view
 CT scan
 MRI

32.  Listhesis causes spinal stenosis with neurogenic claudication
 Primary symptoms are from:
Lateral recess stenosis – from forward slippage of the inferior
articulating process
Disk herniation – contributes to central stenosis caused by intact
neural arch
 Herniated discs are rare at the level of listhesis
 More often level above.
 Radiculopathy involves the nerve exiting under the pedicle of the
subluxed vertebra
General points

33. D/D
Mechanical low back pain
Lumber canal stenosis
lumbar disk herniation
Facet dysfunction
Lumber compression fracture

34. Inverted napoleon’s hat sign
Indicates the presence of bilateral
spondylosis and significant
spondylolisthesis.
The dome of the hat is formed by
the overlying body of L5 vertebra
and the brim is formed
by downward rotation of the
transverse processes.

35. Defect in the pars interarticularis –
‘collar’ around the ‘neck’ of an illusory
‘dog’- oblique xray

37. The bending films
 Demonstrate
persistent motion
and instability
 Disc degeneration
and collapse of the
disc space is an
attempt to stabilize
the motion segment

39. Prognosis
 Dysplastic spondylolisthesis appears at an early age,
severe slip and carries a significant risk of
neurological complications.
 Lytic (isthmic) spondylolisthesis with less than 10 per
cent displacement does not progress after adulthood.
 Degenerative spondylolisthesis is rare before the age
of 50, progresses slowly and seldom exceeds 30 per.

40. Conservative treatment
 Always consider first……………….Everytime!
 Improvement likely if back > leg pain
 Isthmic / degnerative with leg pain: improvement
less likely
 Investigate / treat osteopaenia

41. Conservative treatment (Paediatric)
 Stop aggravating activities
 Gradual mobilisation
 Trunk strengthening
 Period of bracing

42. Conservative treatment (Adults)
Exercises
Aerobics
NSAID’S
Epidural steroids

43. Surgical indications
 Severe back and leg pain that interfere with daily
activity.
 Failed conservative trial
 Abnormal neurology
 Slip more than 50 percent & progressing

44. Surgical goals
Address the pars defect
Decompress the foraminal stenosis
Address the degenerated disc
Address the dynamic instability

45. Operative options
 Direct repair of pars defect
 Decompression and fusion without fixation
 Decompression and fusion with pedicle screw fixation
 Posterolateral insitu fixation
 Partial reduction and fixation
 Complete reduction, fusion and fixation
 Posterolateral interbody fusion and fixation/PLIF
 Trans foraminal interbody fusion/TLIF
 Anterior interbody fusion/ALIF

46. Operative options
 Note:
repair preserves motion segment
Fusion removes motion segment
Reduction should be considered if slip is
>50 percent

47. Interbody support restores disc space height, facilitates
correction of alignment & balance, prevents progression
of sublaxation & provides load sharing to prolong the
life of instrumentation
Fusion can be achieved by many ways like autografts,
allografts, calcium carbonate & phosphate derivatives,
hybrid spacers such as metallic or carbon fibre ramps,
circular cages filled with osteo-inductive materials
Insertion of cage is superior to bone graft alone as it
provides anterior & middle column stabilization.

48. Most of the cases of degenerative Lumbar
Spondylolisthesis can be managed conservatively
But when there is pain with instability of spine with or
without neurological symptoms that makes life unbearable
&/or pt. response to conservative treatment is
unsatisfactory, then surgery is the only option
Decompression followed by fusion & instrumentation
offers potential improvement of symptoms & a better
lifestyle

49. THANK YOU

50. SCORING TECHNIQUE FOR THE OSWESTRY LOW BACK
DISABILITY QUESTIONNAIRE AND NECK
DISABILITY INDEX
1.Score 0-20% : Minimal disability
2.Score 21-40% : Moderate disability
3.Score 41-60% : Severe disability
4. Score 61-80% : Crippled
5.Score 81-100% : Bed bound or exaggerating
symptoms

51.  Includes complete cessation of activity, rehabilitation with
strengthening of the abdominal and paraspinal musculature,
minimization of pelvic tilt, and antilordotic bracing.
 The brace is worn for 23 hours/day for minimum of 3 to 6 months.
If clinical symptoms improve, the brace can be gradually weaned
through a period of part-time wear.
 Vigorous activities are restricted and back, abdominal and core
strengthening exercises are prescribed.
Conservative Management

52. Includes
 Complete cessation of activity,
 Rehabilitation with strengthening of the abdominal
and paraspinal musculature,
 Minimization of pelvic tilt, and
 Antilordotic bracing.
Conservative Management

55. The amount of anterior roll of L5:
 The dome and the anterior surface
of the sacrum are divided into 10
equal parts.
 The scoring is based on the position
of the posterior inferior corner of
the body of the fifth lumbar vertebra
with respect to the dome of the
sacrum.
 The second number indicates the
position of the anterior inferior
corner of the body of the L5
vertebra with respect to the anterior
surface of the first sacral segment.

56. The sacral slope and pelvic tilt
were similar to those of patients
without spondylolisthesis
.
marked retroversion
of the sacropelvic
complex
vertical sacrum
SS- HIGH
PT-LOW
SS- LOW
PT-HIGH

57. Concept of balanced vs unbalanced pelvis
 The balanced pelvis is one in which
compensatory increased lumbar lordosis
and decreased thoracic kyphosis of the
spine are adequate to maintain an adequate
C7 plumbline or normal sagittal balance.

58. Concept of balanced vs unbalanced pelvis
 In the unbalanced, or retroverted, pelvis,
there is high PI because of increased
pelvic tilt (visualized as an anterior
position of the femoral heads relative to
the sacrum) that the spine cannot
accommodate the associated high L5
incidence angle, leading to positive
forward balance.

59. Concept of balanced vs unbalanced pelvis
 unbalanced spine, occurs when the C7
plumbline falls anterior to the femoral
heads on the standing lateral radiograph.
 The spine is balanced when the plumbline
falls on or posterior to the femoral heads.

60. PATHOPHYSIOLOGY
 TRAUMATIC PATHWAY
 DYSPLASTIC PATHWAY
 DEGENERATIVE PATHWAY

61. TRAUMATIC PATHWAY
Erect posture- Centre of Gravity anterior to LS joint
Lumbar spine- forward force and rotate Anteriorly into flexion
about the sacral dome. Initiated by the repetitive cyclic
loading
Supr and infr articular process impingement creates a
bending moment that is resisted by the Pars.
Repetitive impingement- fatigue

62. TRAUMATIC PATHWAY
Stress # of Pars and post. neural arch separates from body
Gap occupied by the fibrous tissue
Non union
Increased shear load to disc though Vertebral
axial load remains unchanged
Subluxation
Premature disc degeneration

63. DYSPLASTIC PATHWAY
Initiated by the cong. defect (dysplasia) in the bony
hook or its catch. -pedicle
-supr articular facet
-infr articular facet
Repeated loading unopposed by bony constraints
Plastic deformation of soft tissue restrains: IV Disc
Antr and postr Long. L
Postr Ligament complex
Subluxation of vertebra

64. DYSPLASTIC PATHWAY
With continuous growth
Slippage and abnormal growth in the involved
vertebral bodies or sacrum
eg -Trapezoid shape of L5
- Rounding of supero anterior aspect of sacrum
- Vertical orientation of the sacrum
- Junctional kyphosis at involved segments
- Compensatory hyperlordosis at the adjacent levels

65. DEGENERATIVE SPONDYLOLISTHESIS
Sagital facets Disc degeneration
No resistance for anterior Disc narrows
translation force Subsequent overloading
of facets
Predilection for slippage .Accelerated arthritic
changes
.Secondary remodelling
.Anterolisthesis
Boden et al - sagital facet angles of > 45 degree at L4-L5 - 25
times greater likelihood of degenerative spondylolisthesis.

66. •Whatever the inciting event - Facet arthritis
- Disc degeneration
and
- Ligamentous
hypertrophy
All contribute to produce the symptoms.
•True deformity of degn spondylolisthesis – Rotatory deformity –
not pure translation
Distort dura and its contents
Exaggerate the appearance of spinal
DEGENERATIVE SPONDYLOLISTHESIS

67. PATHOLOGICAL SPONDYLOLISTHESIS
Due to local or systemic pathological process causing a
defect in the neural arch
Vertebral Subluxation

68. TRAUMATIC SPONDYLOLISTHESIS
High energy trauma
Translational deformity
Fracture of bony hook other than Pars ie:
Pedicle, Superior and Inferior articular facets
Associated multiple bony and STI
Subluxation

69. POST SURGICAL
Laminectomy : Fusion of segments
Removal of > ½ or entire Resection of capsular,
Supraspinous
articular process and Interspinous ligaments
Destabilize the spine
Translational deformity Increasing motion
demand the next
SUBLUXATION
Compression of nerve roots

70. Disc degeneration: MRI
Pfirrmann et al Spine
Grade I Grade II Grade III Grade
IV
Grade V

73. SCORING TECHNIQUE FOR THE OSWESTRY LOW BACK
DISABILITY QUESTIONNAIRE AND NECK DISABILITY INDEX
1. Each of the 10 sections is scored separately (0 to 5 points each) and then
added up
(max. total = 50). Example:
Section 1. Pain Intensity Point Value
A. ___ I have no pain at the moment 0
B. ___ The pain is very mild at the moment 1
C. ___ The pain is moderate at the moment 2
D. ___ The pain is fairly severe at the moment 3
E. ___ The pain is very severe at the moment 4
F. ___ The pain is the worst imaginable 5
2. If all 10 sections are completed, simply double the patient’s score.
3. If a section is omitted, divide the patient’s total score by the number of sections
completed times 5.
Formula: Patient’s Score X 100 = ___________ % DISABILITY
No. of sections completed x 5