Interbody fusion

1. Lumbar Interbody Fusion-
Indications, Techniques, And
Complications
Dr Praveen K Tripathi
27-Jan-16
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2. Introduction
Spinal fusion
• The ultimate goal of
pathologic segmental
symptoms
a fusion is
motion and
the elimination of
its accompanying
• Achieved by the formation of osseous bridging across the
previously mobile level.
• Successful fusion is known as arthrodesis; nonunion is
referred to as pseudarthrosis .
• Three basic requirements for a successful fusion:
▫ Immobilization,
▫ Fusion bed, and
▫ Bone graft
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3. Landmarks in the History of Fusion
• 1911 -Albee First use of tibial graft
• 1911 -Hibbs First use of Iliac crest graft
• 1953 -Watkins First posterolateral fusion (bilateral
transverse process fusion)
• 1950- Harrington Development of instrumentation (used
to treat pediatric scoliosis from polio)
• 2002 -FDA approval of recombinant human bone
morphogenetic protein-2
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4. 27-Jan-16
Indications
Degenerative spondylolisthesis,
isthmic spondylolisthesis,
spinal stenosis,
lumbar spondylosis
intervertebral disc herniation.
Patients with deformity,
Spinal trauma, and
Oncologic conditions
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5. Summary of Evidence-Based Indications for
Fusion
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6. Relative Contraindications for Lumbar
Interbody Fusion
• Three level DDD (except in spinal deformity)
• Single level disc disease causing radiculopathy
w/o symptoms of mechanical low-back pain or
instability
• Severe osteoporosis (possible subsidence of
interbody grafts through the end plates)
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7. Types of Spinal Fusion
•Interbody Fusion
•Posterolateral
Fusion
Types
of
fusion
are
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8. Interbody Fusion (IF)
• Removal of the intervertebral disc (discectomy)
and replacement with a bone graft and/or a
device (spacer or cage) to maintain alignment
and disc height.
• The devices usually contain bone graft material
which facilitates fusion.
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9. Approaches Interbody Fusion
Anterior approach
Anterior lumbar interbody fusion (ALIF)
Transpsoas lumbar interbody fusion (DLIF/direct or
XLIF/eXtreme)
Oblique lumbar interbody fusion (OLIF)
Posterior approach
Posterior lumbar interbody fusion (PLIF)
• “open” TLIF
• minimally invasive techniques
(MasTLIF or MisTLIF)
Midline LIF (MidLIF or MLIF)
Transforaminal lumbar interbody fusion
(TLIF)
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10. Posterolateral fusion (PLF)
• Posterolateral fusion places the bone graft
between the transverse processes
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11. Fusion for DDD-goals
Interbody techniques
• Remove pain generator
• Large surface area for fusion
where majority of spinal load
bearing occur
▫ 90% of the surface area
▫ 80% of the load
• Compressive force through
graft
• Correction coronal and sagittal
alignment
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12. 27-Jan-16
Anterior Techniques
Anterior lumbar interbody
fusion (ALIF): disc is
approached from an anterior
(abdominal) incision.
Advantage - avoidance of
cutting muscles of the back.
Disadvantage is the risk of injury
to structures in the abdomen.
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13. Indications -Anterior lumbar interbody
fusion
Degenerative disc disease with or without radiculopathy
Spondylolisthesis
Failed posterior fusion
Scoliosis
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14. Criteria -associated with a good outcome
after ALIF
(1)Axial back pain aggravated by spinal loading
and fusion,
(2)Radiographic studies consistent with disc
degeneration,
(3)Provocative discography that produces pain
only at the affected levels, and
(4)Dynamic studies demonstrating motion/sagittal
deformity on sagittal views.
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15. Anterior Techniques
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16. Anterior Techniques
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17. Anterior Techniques
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18. Anterior Techniques
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19. Anterior
20%
Posterior
The 80-20 rule of Spine loading
Biomechanics
80%
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RATIONALE FOR ALIF
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21. • With ALIF, an interbody fusion device is used to
redistribute the weight-bearing distribution to the
original ratio.
• According to the Woolf law, the fusion potential
increases if grafts are placed under the direct
compression that supports the placement of the graft
in the anterior column.
Mummaneni PV, Haid RW, Rodts GE. Lumbar interbody fusion: state-of the-art
technical advances. J Neurosurg Spine. 2004;1(1):24-30.
RATIONALE FOR ALIF
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22. • Radiological outcomes, including height restoration
and focal and lumbar lordosis, were superior in
anterior approach, whereas cost, blood loss, and
operative time were greater in ALIF compared with
transforaminal lumbar interbody fusion.
Jiang SD, Chen JW, Jiang LS. Which procedure is better for lumbar interbody
fusion: anterior lumbar interbody fusion or transforaminal lumbar interbody fusion?
Archives of Orthopaedic and Trauma Surgery. 2012;132(9):1259-1266.
RATIONALE FOR ALIF
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23. Anterior lumbar interbody fusion (ALIF)
(A) ALIF interbody device with integral fixation. (B) ALIF implant with anterior plate fixation.
(C) ALIF implant with posterior instrumentation.
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24. Lateral lumbar interbody fusion (LLIF)
• Transpsoas lumbar interbody
fusion (DLIF/direct or
XLIF/eXtreme): the disc is
approached through the psoas
muscle, from an extreme lateral
incision (retroperitoneal) on the
patient’s side.
• The advantage is the avoidance of
back muscles and abdominal
structures required in traditional
fusion procedures.
• The disadvantage is that L5-S1 is
not accessible with this procedure
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25. Indications and Contraindications -lateral
lumbar interbody fusion (LLIF)
• LLIF is most suitable for interbody access from L2 to L4 for
degenerative disc disease with or without instability
• Adjacent segmental disease
• Degenerative spondylolisthesis (grade I or II)
• Complex degenerative scoliotic deformity
contraindications
• LLIF at L5-S1 is generally contraindicated due to obstruction by the
iliac wing.
degenerative spondylolisthesis, greater than 30-degree
• Other relative contraindications include grade III or greater
lumbar
deformities
• Bilateral retroperitoneal scarring
• LLIF is generally not used alone when direct posterior
decompression is necessary, such as with lumbar stenosis or disc
rupture
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26. 27-Jan-16
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27. Oblique lumbar interbody fusion (OLIF):
• Oblique lumbar interbody fusion (OLIF): the
disc is approached from a lateral incision on the
patient’s side.
• The procedure is done "obliquely" (in front of
the iliac crest) which gives access to L5-S1
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28. Anterior Approaches - Contraindications
ALIF - Contraindications
• Calcified aorta
• Prior vascular reconstructive
surgery
• Prior intra-abdominal or
retroperitoneal surgery
• History of severe pelvic
inflammatory disease
• Prior anterior spinal surgery
Transpsoas -Contraindications
• At L5/S1 and sometimes at L4/5
because of obstruction from iliac
crest
• Prior retroperitoneal surgery or
scarring
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29. Advantages of OLIF than direct anterior
approach
• Anterior to psoas muscle-avoids
injury to psoas muscle and
lumbar plexus there by less
incidence of cruralgia
• Away from peritoneum and
vasculature ( beware of
ileolumbar vein and transitional
bifircation of great vessels)
• Preserves sympathetic plexus-
decreased incidence of
retrograde ejaculation
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30. • Direct visualisation and
discectomy, easy to do
end plate preparation
• Can be performed L2-L3
to L4-L5
• Upto 3 level fusion can be
done using 4 cm incion by
“sliding window”
technique
Rodgers WB, Gerber EJ, Patterson J. Intraoperative and early postoperative complications in
extreme lateral interbody fusion: an analysis of 600 cases. Spine (Phila Pa 1976) 2011;36:26-32.
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Advantages of OLIF....
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31. Advantages of OLIF
• Lesser incidence of hernias and ileus
• Decreased blood loss
• Increased surface area of the OLIF cage which is 3
times more than TLIF cage gives better and strong
arthodesis
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32. Advantages of anterior approach
• nerve root retraction and entrance into the spinal canal
are unnecessary, thereby eliminating epidural scarring
and perineural fibrosis
Chung SK, Lee SH, Lim SR, et al. Comparative study of laparoscopic L5-S1 fusion versus open
mini-ALIF, with a minimum 2-year follow-up. Eur Spine J. 2003;12 (6):613-617
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33. Advantages Anterior Approaches
• Larger graft
placement without
manipulation of
nerve roots
• Deformity
correction
• Indirect
decompression
• Greater fusion
surface area
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34. Advantages Anterior Approaches
• Preservation of
posterior stabilizing
structures
▫ Interspinous ligaments
▫ Facet capsules
• No muscle disruption
& Postop muscle
atrophy
▫ Chronic pain
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35. ALIF - Complications
• Retrograde ejaculation
▫ Most series < 1% to 7%
▫ Much higher (10 times) with transperitoneal
approaches and with laparoscopic approaches
• Blunt dissection versus electrocautery
• Large majority of patients recover within 6 – 12
months
• Bowel & Ureter injury
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36. Extreme Lateral - Complications
• Reporting of complications has been inconsistent 3% -
60%)
• Genitofemoral, ilioinguinal or lateral femoral cutaneous
nerve injuries -Thigh numbness, paresthesias
• Femoral nerve -Leg weakness
• Damage to lumbosacral plexus which progressively
migrates anteriorly beginning at L1/2 level
• Psoas muscle injury and pain
• Traction injury to plexus postop dysesthesias
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37. Posterior Lumbar Interbody Fusion (PLIF)
• The first successful report of a posterior lumbar
interbody fusion (PLIF) dates to 1940 by Cloward
Indications
• Recurrent disc herniation
• Failed back surgery syndrome
• Spondylolisthesis
• Bilateral midline disc herniation
• Segmental instability
• Degenerative disc disease
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38. Posterior Lumbar Interbody Fusion (PLIF)
Contraindications to performing PLIF include
• Osteoporosis,
• Discitis,
• Subchondral sclerosis, and
• Adhesive arachnoiditis.
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39. The classic PLIF technique consists of three surgical
steps:
(1) Laminectomy or laminotomy with
complete facetectomy,
(2) Removal of the intervertebral disc, and
(3) Fusion
partial or
Posterior interbody techniques (PLIF)
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40. Posterior interbody techniques (PLIF)
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41. Posterior interbody techniques (PLIF)
A, The nerve root and dural sac are
retracted medially, creating maximal
exposure of the interbody space.
B, The interbody device is inserted
bilaterally and packed with bone for
maximal fusion.
C, A pedicle screw is used to distract
the disc space. The trajectory and
depth of the screw are important for
successful fusion.
D, Next, using either a screw or a
rod construct, the final arthrodesis
is reinforced until biologic fusion
is achieved.
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42. Complications of PLIF
PLIF is a technically challenging and demanding procedure and
consequently is associated with complications.
• Nerve root injury
▫ The nerve root that exits at the level above the disc space often
lies near the interbody graft as it is being placed and can easily
be injured.
• Incidental durotomy
• Wrong -level surgery,
• Adjacent-level disease,
• Graft retropulsion, and pseudarthrosis in the case of
instrumentation with PLIF.
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43. Lumbar – Transforaminal Lumbar Interbody
Fusion (TLIF)
• Transforaminal lumbar interbody fusion (TLIF)
reestablishes anterior column support while allowing for
posterior fixation, thereby imparting improved fusion
rates because of circumferential support.
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44. Lumbar – Transforaminal Lumbar Interbody
Fusion (TLIF)
Indications
• Degenerative disc disease,
• Low-grade spondylolisthesis
• Synovial cysts (when fusion is required)
• Multiply recurrent disc herniations, and foraminal stenosis
associated with deformity.
• TLIF is ideal for grade I or II spondylolisthesis with unilateral
symptoms.
Contraindicated in
• Complete disc desiccation
• Presence of extensive osteophytes- limits disc distraction.
• Extensive scarring from prior posterior surgery serves as a
relative contraindication.
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45. TLIF utilizes an imagined
quadrangular space between
the transverse processes
of the vertebral bodies
adjacent to the affected disc
space and the traversing
nerve root medially
Lumbar – Transforaminal Lumbar Interbody
Fusion (TLIF)
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46. Lumbar – Transforaminal Lumbar Interbody
Fusion (TLIF)
• TLIF is performed to remove a portion of a disc that is
the source of back or leg pain.
• Bone graft is used to fuse the spinal vertebrae after the
disc is removed.
• However, the TLIF procedure places a single bone graft
between the vertebrae from the side, rather than two
bone grafts from the rear as in the PLIF procedure.
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47. Lumbar – Transforaminal Lumbar Interbody
Fusion (TLIF)
Decompression Removing the facet joint and disc relieves pressure on the
compressed spinal nerve, allowing it to return to the proper
position.
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48. Lumbar – Transforaminal Lumbar Interbody
Fusion (TLIF)
Graft Placement
A single bone graft is placed in the
disc space from the lateral
Preparing for Fusion a motorized instrument is
used to remove the top (cortical) layer of the
transverse processes
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49. Lumbar – Transforaminal Lumbar Interbody
Fusion (TLIF)
The rod and screw instrumentation
provides stability to the spine
Bone Graft
Bone grafting can be done with pieces of a patient’s own
bone (autograft), processed bone from a bone bank
(allograft), or a bone graft substitute (demineralized
bone,ceramic extender, or bonemorphogenetic protein).
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50. Complications -TLIF
• The most frequent include blood loss requiring
transfusion
• Lumbar wound infection
• Postoperative radiculitis,
• Cage subsidence or extrusion, and pseudoarthrosis
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51. Posterior interbody
techniques (PLIF TLIF) -
Problems
• Limited window to disc
space
• Thecal sac/nerve root
retraction
▫ Weakness (2-7%)
▫ Postop neuralgia (5%)
▫ Dural tears (5-20%)
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52. Posterior interbody techniques (PLIF TLIF) •
Problems
• Graft size vs. nerve root injury vs endplate fracture
• Suboptimal restoration of disc height and surface area
for fusion
• Poor visualization of disc space/endplates
• Limited endplate preparation for fusion
• Endplate damage/fractures graft subsidence
• Time
• Blood loss
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53. TLIF- advantages
• TLIF obviates the morbidity from the retroperitoneal
dissection and subsequent posterior fixation required from
anterior lumbar interbody fusion (ALIF).
• Unlike PLIF, TLIF requires minimal to no retraction on the
thecal sac and nerve roots while still providing 360 degrees
of support.
• Because TLIF utilizes a more lateral trajectory, it can be
performed in the setting of previous surgery with
identifiable landmarks and a cleaner plane of dissection.
• The average length of stay for both minimally invasive and
open TLIF ranged between 3 and 6 days
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54. Posterolateral fusion (PLF)
• Posterolateral fusion places the bone graft between the
transverse processes (the bony protuberances on the
vertebrae) rather than the intervertebral disc space,
which is left intact.
• The approach is through a posterior (back) incision, and
a laminectomy is typically required to gain access.
• PLF is usually accompanied by fixation.
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55. Posterolateral
fusion (PLF)
The landmarks used
for cannulating the
pedicles are the
meeting point of the
pars interarticularis,
the superior
articulating process,
and the transverse
process
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56. Complications open posterior lumbar
fusion
• Mortality rates have been found to be 0.15% to 0.29%.
• The most common preventable cause of death- analgesia overuse
Short term complications
• Surgical site infections, are among the most common.
• Incidental durotomy causing a cerebrospinal fluid leak,
• Spinal epidural hematoma,
• Cauda equina syndrome,
• Neurologic injury,
• Rhabdomyolysis, and sudden vision loss
Long-term complications
• Pseudarthrosis,
• Chronic pain from the donor allograft site.
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57. Advantages of Lumbar Interbody Fusion
Compared with Posterolateral Fusion
• Interbody grafts are compressed by 80% of spinal
loads, whereas posterolateral grafts are compressed by
20%
• Interbody grafts occupy 90% of intervertebral surface
area, whereas posterolateral grafts occupy only 10%.
• The interbody space is more vascular than the
posterolateral space, increasing chances for fusion.
• Interbody grafts can better restore coronal and sagittal
balance.
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58. OLIF cage TLIF/PLIF cage
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59. Cost of Lumbar Spine Surgery in India
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61. Post op
• VAS -1
Restoration of disc
space height
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62. Key points…..
• Both anterior and posterior approaches for interbody fusion are associated with
good fusion rates and outcomes in patients with symptomatic lumbar degenerative
disease.
• Anterior approaches allow better access to and visualization of the disc and
endplates which facilitate:
▫ More complete discectomy
▫ Larger surface area for fusion
▫ Better endplate preparation
▫ Larger graft placement for disc height restoration and lordosis
• With a good access surgical team, the complications associated with ALIF are
minimal
• Extreme lateral interbody fusion is a relatively new procedure. As surgeons
become more proficient in the operation and as surgical technique is refined,
sensory dysesthesias and psoas trauma associated with the procedure are
becoming less prevalent.
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63. • OLIF is a minimally invasive fusion procedure
• Lesser complication rate when compared to ALIF
• Longterm follow up (5 and half years)of patients with
OLIF showed similar outcome as that ALIF with
lesser morbidity
Saraph V, Lerch C, Walochnik N, Bach CM, Krismer M, Wimmer C. Comparison of
conventional versus minimally invasive extraperitoneal approach for anterior
lumbar interbody fusion. Eur Spine J 2004;13:425-31.
Key points…..
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