PLIF with cage alone

최우진 , 안형준 , 전기현 , 김현성 ,김관태

Department of neurosurgery,

Hurisarang Spine Hospital

Daejeon, Korea

Lumbar Interbody fusion

Cloward introduced PLIF in 1953 Transforaminal LIF ( TLIF ) Anterior LIF ( ALIF ) Microendoscopic LIF Percutaneous endoscopic LIF

Usually combined with pedicle screw

From 1998 to 2008

1092 PLIF patients with only a cage

During the period, we had performed almost lumbar fusion surgeries with only a cage without pedicle screw fixation.

PLIF with cage alone

년 98 99

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01

02

03

04

05

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07 08 총

N 61 92 86 78 78 83 80 81 129

160

164 1092

Introduction

Postero-lateral region of the endplate provides the greatest resistance to subsidence while the central region provides the least resistance.

(Spine 2004, Lowe thomas G. MD)

Proper preparation of the endplate prevents subsi-dence and increases fusion rate

( complete removal of cartilaginous endplate, com-plete preservation of bony cortex. )

( spine 2003, Oxland TR)

Large Cage Interbody fusion cages with larger area of contact

between cage and vertebral endplate produces a lower stress distribution pattern. ( Spine 2005 Kumar, Naresh MS )

A larger diameter solid support has the greater maximun load of failure and the lower the risk of subsidence. (Spine 2004, Lowe thomas G. MD)

The load-bearing capabilities of the open box cage are superior to those of the fenestrated tube cage (Spine 2006 Matsumura, Akira MD)

local bone chipVs Allo-bone, iliac bone , hydroxyapatate block, BMP

PLIF using cages impacted with laminar bone chips is a useful method when considering the time required for surgery and the morbidity of the autograft donner sites. (Spine 2005 Kim, K S)

A 100% bony union rate was obtained 12 months after PLIF with only local bone ( spine 2003 Miura Y)

A surgical technique of PLIF, with use of posterior elements cut into small corticocancellous chips measuring 2-4 mm as graft materal, has distinct advantages. (Clin Orthop Relat Res. 1985 Simmons JW)

PLIF without screw

To restore stability with no additional instrumenta-tion, the cages must provide sufficent distraction of the vertebrae and adequate tension in the annu-lus ( Spine 2000 Goh JC )

PLIF without PLF had advantages of the elimina-tion of donner site pain, shorter operating time, and less blood loss. (Spine 2006 Kim KT MD)

PLIF with screw Performing PLIF using stand-alone metallic cages,

especially after total resection of the facet joints, is not advocated unless supplimental instrumentation is utilized. (Spine 2006 Cassinelli EH)

The combination of cages with dorsal instrumenta-tion achieves a more precise realignment and has a lower rate of cage-associated complications ( Z or-thop Ihre Grenzgeb 2003 Diedrich O)

Cage migration

The rates of cage migration in patient with no pos-terior instrumentation was significantly higher compared with that rate in those with posterior in-strumentation ( 16.7 % vs 0%) (Spine 2005 Chen, Liang MD)

Factors of cage migration – lack of posterior in-strumentation and total facectectomy. (Spine 2005 Chen, Liang MD)

An Interbody fusion of lumbar segmental instabil-ity should be combined with pedicular instrumen-tation( Z orthop Ihre Grenzgeb 2003 Diedrich O)

Cage 가 빠지는 주된 원인이 Screw 를 하지 않아서 라고 생각하십니까 ?

PLIF cage alone ( N=768, 1998-2006) Retropulsion : 5 cases ( 0.6 %) Retry PLIF Cage alone, not screw Pseudoarthrosis : 2 cases PSF and intertransverse fusion

Wound infection : 3 cases irrigation & resutured within 1 weeks not cage removal

No neurologic deficit

23/M, PEEK cage

Varlock cage replacement

POD # 9days, Lt leg pain

F/U 1 yrs

24/M, Varlock cage (11mm) inserted midline, contact

13mm reinserted laterallyand intercage center bone

POD# 1weeks, # 2 weeks

47/F Varilift (11mm)cage POD #1 weeks

Varian(13mm) cage reinsertion F/U 3 yr flexion

Cause of retropulsion

0.6 % migration rate (5 / 768) reinsertion cage alone without screw fixation

Cage insertion method >> combined screw

sufficent distraction of the vertebrae and adequate tension in the annu-lus ( Spine 2000 Goh JC )

Proper preparation of the endplate prevents subsidence and increases fusion rate ( spine 2003, Oxland TR)

PLIF with cage alone is more effective method in specific cases

1. One level fusion in multiple level instability

2. Junction instability after screw fusion

1. Multiple level instability

Screw 보다 Junctional instability 가 적다 .

2. Junctional instability of screw fusion

Screw 후 Junctional instability 에 cage alone 아주 효과적이다 .

My history of CAGES

Carbon CH PEEK Round

Varlock Varlift TYM Varian

Upgrade expandible cage (Varian )

56/F 3mo 6mo 5 yr

early, long term F/U stable

Varian cage (Anchor)

Difinite expanded tripozoidal cage stabilize lordotic curvature After inserted and expanded, bone chip

filled ( clean, maximun amount chip) Wide contact area and additional firm im-

pacted bone chip area is spread pressure Anterior angled shape cage insert easy and

protect bony cortex

Varian cage (Anchor)

Simple one turn expansion (2-3mm) – strong hardware, long stable.

Vs weak turn screw method Select fitting cage, various size

( 9 -14mm, 2.4-2.7-3.0 cm) Less subsidence, high fusion rate in long

term F/U

Cage size AP diameter < 4 cm : 24 mm 4-5 cm : 27 mm > 5 cm : 30 mm

Not fitting cage Fitting cage

14mm 2.7cm

Varian Cage (N=200 /2004.6-2006)

M:F 68:132 Age 55.5 (14-76)

Degenerative spondylolisthesis 89 Lytic spondylolisthesis 25 Narrowoing & wedging anlgulation 86

L2-3 4 L3-4 34 L4-5 156 L5-S1 32 Level 228 ( 2,3 level = 27 )

Varian Cage (N=200)

No cage related Cx ( migration, hardware Fx )

Outcome (modified macnab classification)

Excellent : 75 Good : 110 ( 93% ) Fair : 15 Poor : 0

Radiologic fusion ( spine1991 Brantigan )

All cases radiologic fusion by flex/extension x-ray

F/U Radiography of Varian Cage

AAB

C

Disc height (A+B)/C Segmental Total lordosis

Radiographic analysis

preop

Postop. o

PO 6mo

PO1yr

Intervertebral disc height

48.3(100)

69.7(144)

67.8(140)

64.8(134)

Segmental lumbar lordosis

15.0(100)

15.8(105)

18.1(121)

18.9(126)

Total lumbar lordosis

40.5(100)

36.7( 91)

40.0( 99)

40.1( 99)

Varian Cage (N=200)

Epidural anesthesia Op time (1 level) : 112 minute Bleeding loss : 191 cc All local bone chip used Center bone inserted between cages Bed rest postop 5 day TLSO brace postop 3 months

High grade spondylolisthesis with severe disc space narrowing

Lateral wedging, scoliotic change

45/F, two level PLIF

F/U 2 yrs

POD # 3mo 6months

F/U 5 yrs flex/ext

51/F, severe lysis & listhesis POD#1 F/U 6mo

F/U 2yr F/U 5 yrs flex/ext/AP

Conclusion of cage alone

Had many advantages of minimal invasive surgery

Could perform almost lumbar fusion surgeries

More effective fusion method in specific cases

Expandible Varian cage (anchor) is useful,

good outcome, radiologic stable in long term F/U

Thank you for your attention !