Minimally Invasive Surgical Approaches in the Management of Tuberculosis of the Thoracic and Lumbar Spine

SYMPOSIUM: MINIMALLY INVASIVE SPINE SURGERY

Minimally Invasive Surgical Approaches in the Managementof Tuberculosis of the Thoracic and Lumbar Spine

Nitin Garg MCh, MS, MRCS(Edin), Renuka Vohra DNB, DMRD

� The Association of Bone and Joint Surgeons1 2014

Abstract

Background Spinal tuberculosis is the most common

form of skeletal tuberculosis. Various approaches have

been described for surgical management of spinal tuber-

culosis, but many entail wide exposures with attendant

morbidity; whether minimally invasive surgical (MIS)

approaches are suitable is unknown.

Questions/purposes We evaluated (1) neurologic results,

(2) radiographic results, and (3) complications in patients

with thoracic and lumbar spinal tuberculosis treated with

two MIS approaches.

Methods We retrospectively evaluated 22 patients with

thoracic and lumbar tuberculosis managed surgically from

October 2008 to February 2011 using MIS methods; one

patient was lost to followup, leaving 21 patients with a mini-

mum followup of 15 months (mean, 30 months; range,

15–59 months) for analysis. MIS approaches were used for

patients with disease below D6 and minimum pedicle diam-

eters of 4.5 mm to permit percutaneous screw placement. The

MIS approach was divided into two groups depending on the

extent of destruction of the vertebral body: a posterior-only

group (n = 9), where posterior transpedicular decompression

sufficed, and the hybrid group (n = 12), requiring anterior

debridement and ventral-column reconstruction by conven-

tional or mini-open thoracotomy. All but two patients with

more than two contiguous bodies involvement underwent MIS

posterior fixation by percutaneous transpedicular screws.

Plain radiographs were evaluated for deformity correction and

correction maintenance. Neurologic recovery and complica-

tions were ascertained by chart review.

Results All patients with neurologic deficits recovered

completely with no motor deficits at followup; 13%

improved by three grades, 53% by two grades, and 33% by

one grade. Mean correction was 2.5� (thoracic) and 8�(lumbar) in the posterior-only group and 4.2� in the hybrid

group. Some correction loss occurred with healing (2� and

1.6� in the posterior-only and hybrid groups, respectively),

but in none of those who had fixation did this progress to

more than preoperative status. Two of 22 patients (9%) had

complications. One had a malposition of L5 screw causing

painful radiculopathy without motor deficit and required

repositioning. The other had an intraoperative dural tear

repaired by onlay fascial patch and cerebrospinal fluid

diversion. There were no approach-related complications,

neurologic deterioration, or implant fatigue at last

followup.

Each author certifies that he or she, or a member of his or her

immediate family, has no funding or commercial associations

(eg, consultancies, stock ownership, equity interest, patent/licensing

arrangements, etc) that might pose a conflict of interest in connection

with the submitted article.

All ICMJE Conflict of Interest Forms for authors and Clinical

Orthopaedics and Related Research editors and board members

are on file with the publication and can be viewed on request.

Clinical Orthopaedics and Related Research neither advocates nor

endorses the use of any treatment, drug, or device. Readers are

encouraged to always seek additional information, including FDA

approval status, of any drug or device before clinical use.

Each author certifies that his or her institution approved or waived

approval for the human protocol for this investigation and that all

investigations were conducted in conformity with ethical principles of

research.

N. Garg (&)

Department of Neurosurgery, Bhopal Memorial Hospital and

Research Centre, Near Karond Square, Bhopal 462038, India

e-mail: [email protected]

R. Vohra

Department of Radiodiagnosis, Bhopal Memorial Hospital and

Research Centre, Near Karond Square, Bhopal 462038, India

123

Clin Orthop Relat Res

DOI 10.1007/s11999-014-3472-6

Clinical Orthopaedicsand Related Research®

A Publication of The Association of Bone and Joint Surgeons®

Conclusions We found evidence of neurologic recovery,

avoidance of deformity progression, and few complications

with these MIS approaches. Comparative trials are called

for between open and MIS approaches for patients with

spinal tuberculosis.

Level of Evidence Level IV, therapeutic study. See

Instructions for Authors for a complete description of

levels of evidence.

Introduction

Tuberculosis of the spine, a paucibacillary disease, is one of

the common forms of skeletal tuberculosis [18]. The man-

agement goals are to eradicate infection, prevent or treat

neurologic deficits, and correct and avoid spinal deformity

progression. Current surgical methods include anterior

debridement, decompression, fusion followed by ventral or

posterior instrumentation, and posterior decompression with

or without dorsal fixation [9, 10, 13, 14, 20, 22, 23, 25, 27].

Conventional surgical approaches to the ventral aspect

include thoracotomy with extrapleural or transpleural

access, lateral extracavitary and costotransversectomy

approaches for the thoracic spine, and retroperitoneal

approaches for the lumbar spine [7, 20, 22, 25, 27]. These are

extensive approaches with associated morbidity [15].

Minimally invasive surgical (MIS) approaches are

increasingly being used in managing various spinal disor-

ders, such as degenerative spine, trauma, and tumors [2, 3,

16, 21, 26, 28]. Video-assisted thoracoscopic anterior sur-

gery (VATS) has been described as an MIS option for

managing tuberculosis of the dorsal spine [10, 11, 15].

However, more research into whether these approaches are

suitable for the management of spinal tuberculosis is needed.

We therefore evaluated (1) neurologic results, (2)

radiographic results, and (3) complications in patients with

tuberculosis of the thoracic and lumbar spine treated using

either a posterior-only MIS approach or a hybrid MIS

approach (conventional or mini-open anterior approach

plus MIS posterior fixation).

Patients and Methods

Study Patients

In this retrospective study, we evaluated 22 patients with

tuberculosis of the dorsal (below D6) and lumbar spine

who were managed using MIS techniques between October

2008 and December 2011. During that same period, a total

of 59 patients underwent various surgical procedures for

tuberculosis involving the entire spine.

The protocol followed for managing these patients was

the ‘‘middle path regimen’’ described by Tuli [30]. All

patients with peridiscal involvement, preserved vertebral

body height, and no neurologic deficits were managed by

ambulatory antitubercular therapy (ATT) with an external

orthosis and close clinical and radiographic followup.

Surgery was considered in those with persistent severe

disabling pain, radicular pain, neurologic deficits, and

clinical and radiographic progression of disease despite

ATT.

During the period in question, our general indications

for the MIS approach were for disease involving the tho-

racic spine below D6 and the lumbar spine and minimum

pedicle diameters of 4.5 mm. Level of disease was the

most important factor in deciding between conventional

and MIS approaches, in addition to limitations in available

instrumentation and surgeon experience. Of the 59 patients,

37 underwent conventional procedures for the following

reasons: level of disease (n = 26), nature of disease

(n = 4), and hardware limitation (n = 7) (Fig. 1). Four

patients had disease at the craniovertebral junction, 10 at

the cervical spine, and four at the cervicothoracic spine. In

the thoracic spine, eight patients with disease above the D6

level had conventional exposures due to difficulty and our

inexperience in using mini-open retractors for exposure

and insertion of percutaneous transpedicular screws at

these levels. Four patients with en plaque type of tuber-

culosis with epidural granulation causing cord compression

over multiple levels or predominant granulation situated

dorsally without much destruction of the vertebral bodies

underwent conventional hemilaminectomy (one patient)/

laminectomy (three patients). Seven patients had hardware

limitations: three with pedicle diameters of less than

4.5 mm precluding usage of percutaneous screws and four

in the early part of our series when the Longitude1 System

(Medtronic, Inc, Minneapolis, MN, USA) was not available

to avoid using the lordotic precontoured rods of the Sex-

tant1 System (Medtronic, Inc) in the thoracic spine.

Of the 22 patients included in this study, one patient was

lost to followup after 3 months, leaving 21 patients with a

minimum followup of 15 months (mean, 30 months; range,

15–59 months) for analysis. Mean age was 44 years

(range, 18–75 years).

Medical Management

The presenting symptoms were back pain, radicular pain,

and myelopathy (Tables 1, 2). We evaluated neurologic

function using American Spinal Injury Association (ASIA)

grading [4] and myelopathy using Nurick’s grading [19].

ASIA grades include Grade A representing complete sen-

sory or motor function impairment below the affected

Garg and Vohra Clinical Orthopaedics and Related Research1

123

spinal cord segment, Grade B representing complete motor

impairment, Grade C representing incomplete (severe)

motor impairment, Grade D representing incomplete (less

severe) motor impairment, and Grade E representing nor-

mal sensory and motor function. Nurick’s grades include

Grade 0 representing intact, mild radiculopathy without

myelopathy, Grade 1 representing mild myelopathy with

no difficulty in walking, Grade 2 representing mild to

moderate myelopathy with slight difficulty in walking that

does not prevent full-time employment, Grade 3 repre-

senting moderate myelopathy with difficulty in walking

that prevents full-time employment or ability to do

household work but not so severe as to require someone’s

help to walk, Grade 4 representing moderate to severe

myelopathy with ability to walk with someone’s help or

with a frame, and Grade 5 representing severe myelopathy

leaving individuals chairbound or bedridden.

Initial imaging included radiographs, MRI with contrast,

and CT of the spine to identify the level of the disease,

extent of vertebral body destruction and collapse, degree of

deformity (Cobb’s angle), location of the abscess and

granulation tissue, and extent and location of thecal sac

compression. Followup MRI scans were taken at 3 months

of treatment to assess adequacy of response to medical

treatment and to monitor disease progression and at

12 months to assess healing of tuberculosis and to decide

about continuation of ATT. The scans were done early if

the patient did not improve or deteriorated clinically.

Healing was defined as complete resolution of vertebral

body edema and resolution of prevertebral, paravertebral,

and epidural granulation. ATT consisted of four drugs

(isoniazid 5 mg/kg, rifampicin 10 mg/kg, ethambutol

15 mg/kg, and pyrazinamide 25 mg/kg) for 3 months fol-

lowed by two drugs (isoniazid and rifampicin) for 9 to

12 months depending on the resolution of the disease based

on MRI findings. Second-line ATT was initiated in those

with multidrug-resistant strains based on culture reports or

radiographic progression on first-line agents. Routine his-

topathologic and microbiologic analysis was performed on

the pus and necrotic granulation material. This included

Fig. 1 A flowchart illustrates the process of choosing conventional methods versus MIS methods and the posterior-only MIS approach versus

the hybrid MIS approach.

Minimally Invasive Surgery for Tuberculosis

123

Ta

ble

1.

Cli

nic

ald

etai

lso

fp

atie

nts

inth

ep

ost

erio

r-o

nly

gro

up

(n=

10

,o

ne

lost

tofo

llo

wu

p)

Pat

ien

tA

ge

(yea

rs)

Sex

Cli

nic

alp

ictu

reL

evel

Pro

ced

ure

Fo

llo

wu

p

(mo

nth

s)

Neu

rolo

gic

stat

us

14

7F

emal

eB

ack

pai

n,

par

apar

esis

,

Gra

de

C*

D1

1-L

1M

IStr

ansp

edic

ula

r

dec

om

pre

ssio

no

nly

53

No

defi

cits

,G

rad

eE

22

2M

ale

Bac

kp

ain

,p

arap

ares

is,

Gra

de

C,

pro

gre

ssio

no

n

AT

Tfo

r3

mo

nth

s

Mu

ltip

leth

ora

cic

(Fig

.3)

MIS

tran

sped

icu

lar

dec

om

pre

ssio

no

nly

3R

esid

ual

Gra

de

2�

spas

tici

ty;

lost

tofo

llo

wu

p

35

3F

emal

eB

ack

pai

n,

par

apar

esis

,

Gra

de

C

D1

1-D

12

MIS

tran

sped

icu

lar

dec

om

pre

ssio

nan

dP

CS

fix

atio

n

55

No

defi

cits

,G

rad

eE

45

5F

emal

eB

ack

pai

n,

par

apar

esis

,

Gra

de

C

D1

1-D

12

MIS

tran

sped

icu

lar

dec

om

pre

ssio

nan

dP

CS

fix

atio

n

47

No

defi

cits

,G

rad

eE

56

2F

emal

eB

ack

pai

n,

par

apar

esis

,

Gra

de

D

D9

-D1

0M

IStr

ansp

edic

ula

r

dec

om

pre

ssio

n(e

nd

osc

op

e

assi

sted

)an

dP

CS

fix

atio

n

25

Imp

rov

ed;

no

mo

tor

defi

cits

,

Gra

de

E;

resi

du

alG

rad

e2

spas

tici

ty

67

5M

ale

Bac

kp

ain

,p

arap

leg

ia,

Gra

de

C

D8

-D9

(Fig

s.4

,5

)

MIS

tran

sped

icu

lar

dec

om

pre

ssio

n(e

nd

osc

op

e

assi

sted

)an

dP

CS

fix

atio

n

29

Imp

rov

ed;

no

mo

tor

defi

cits

,

Gra

de

E;

resi

du

alG

rad

e2

spas

tici

ty

77

4M

ale

Bac

kp

ain

,b

ilat

eral

L5

rad

icu

lop

ath

y

L4

-L5

MIS

hem

ilam

ino

tom

y,

dec

om

pre

ssio

nan

dP

CS

fix

atio

n

59

No

rad

icu

lar

pai

n

84

2F

emal

eB

ack

pai

n,

bil

ater

alL

5

rad

icu

lar

pai

n,

pro

gre

ssio

no

nA

TT

L3

-L4

MIS

hem

ilam

ino

tom

y,

dec

om

pre

ssio

n,

and

PC

S

fix

atio

n

52

No

pai

n

92

9F

emal

eB

ack

pai

n,

bil

ater

alL

5

rad

icu

lop

ath

y

L4

-L5

(Fig

.6)

MIS

hem

ilam

ino

tom

y,

dec

om

pre

ssio

n,

and

PC

S

fix

atio

n

44

No

pai

n

10

52

Fem

ale

Bac

kp

ain

,ra

dic

ulo

pat

hy

L1

-L2

MIS

tran

sped

icu

lar

dec

om

pre

ssio

n,

and

PC

S

fix

atio

n

15

Imp

rov

ed;

no

defi

cits

*A

mer

ican

Sp

inal

Inju

ryA

sso

ciat

ion

gra

de

for

neu

rolo

gic

defi

cit

(Gra

de

A–

E);

�N

uri

ck’s

gra

de

for

spas

tici

ty(G

rad

e0

–5

);A

TT

=an

titu

ber

cula

rth

erap

y;

MIS

=m

inim

ally

inv

asiv

esu

rger

y;

PC

S=

per

cuta

neo

us

tran

sped

icu

lar

scre

w.


123

Ta

ble

2.

Cli

nic

ald

etai

lso

fp

atie

nts

inth

eh

yb

rid

gro

up

(n=

12

)

Pat

ien

tA

ge

(yea

rs)

Sex

Cli

nic

alp

ictu

reL

evel

Pro

ced

ure

Fo

llo

wu

p(m

on

ths)

Neu

rolo

gic

stat

us

15

5F

emal

eB

ack

pai

n,

par

apar

esis

,G

rad

eD

*D

10

-D1

1D

LT

,R

Pl,

corp

ecto

my

,fu

sio

nw

ith

rib

gra

ft,

and

PC

Sfi

xat

ion

48

Imp

rov

ed;

no

defi

cits

,

Gra

de

E

23

4M

ale

Bac

kp

ain

,p

arap

ares

is,

Gra

de

DD

10

-D1

1D

LT

,R

Pl,

corp

ecto

my

,fu

sio

nw

ith

ilia

ccr

est

gra

ft,

and

PC

Sfi

xat

ion

40

Imp

rov

ed;

no

defi

cits

,

Gra

de

E

34

2M

ale

Bac

kp

ain

D1

0D

LT

,R

Pl,

corp

ecto

my

,fu

sio

nw

ith

cag

e,an

d

PC

Sfi

xat

ion

26

Imp

rov

ed;

no

defi

cits

,

Gra

de

E

44

0F

emal

eB

ack

pai

n,

par

apar

esis

,G

rad

eC

D1

0-D

11

DL

T,

RP

l,co

rpec

tom

y,fu

sio

nw

ith

ilia

ccr

est

gra

ft,

and

PC

Sfi

xat

ion

22

Imp

rov

ed;

no

defi

cits

,

Gra

de

E

54

5M

ale

Bac

kp

ain

,p

arap

ares

is,

Gra

de

BD

11

-D1

2D

LT

,R

Pl,

corp

ecto

my

,fu

sio

nw

ith

cag

e,an

d

PC

Sfi

xat

ion

20

Imp

rov

ed;

no

defi

cits

;

Gra

de

E,

per

sist

ent

bac

k

pai

n

63

0F

emal

eB

ack

pai

n,

par

apar

esis

Gra

de

DD

9-D

10

DL

T,

RP

lap

pro

ach

,d

eco

mp

ress

ion

,fu

sio

n

wit

hil

iac

cres

tg

raft

,an

dP

CS

fix

atio

n

18

Imp

rov

ed;

no

defi

cits

,

Gra

de

E

72

5M

ale

Bac

kp

ain

,d

efo

rmit

y(g

ibb

us)

L2

-L3

Ret

rop

erit

on

eal

app

roac

h,

corp

ecto

my

,

fusi

on

wit

hca

ge,

and

PC

Sfi

xat

ion

18

Imp

rov

ed;

no

defi

cits

;

occ

asio

nal

bac

kp

ain

84

1F

emal

eB

ack

pai

n,

par

apar

esis

,G

rad

eC

D1

0-D

11

MIS

tho

raco

tom

yu

sin

gtu

bu

lar

retr

acto

rs,

fusi

on

wit

hil

iac

cres

tg

raft

,an

dP

CS

fix

atio

n

18

Imp

rov

ed;

no

defi

cits

,

Gra

de

E

91

8F

emal

eB

ack

pai

n,

par

apar

esis

,G

rad

eC

D9

-D1

0(F

ig.

8)

MIS

tho

raco

tom

yu

sin

gtu

bu

lar

retr

acto

rs,

fusi

on

wit

hil

iac

cres

tg

raft

,an

dP

CS

fix

atio

n

17

Imp

rov

ed;

no

defi

cits

,

Gra

de

E

10

26

Fem

ale

Bac

kp

ain

,p

arap

ares

is,

Gra

de

DD

8-D

10

MIS

tho

raco

tom

yu

sin

gtu

bu

lar

retr

acto

rs,

dec

om

pre

ssio

nan

du

nin

stru

men

ted

fusi

on

wit

hil

iac

cres

tg

raft

17

Imp

rov

ed;

no

defi

cits

,

Gra

de

E

11

31

Fem

ale

Bac

kp

ain

,p

arap

ares

is,

Gra

de

CD

7-D

8M

ini-

tho

raco

tom

y,

dec

om

pre

ssio

n,

fusi

on

wit

hil

iac

cres

tg

raft

,an

dP

CS

fix

atio

n

16

Imp

rov

ed;

Gra

de

E,

resi

du

alG

rad

e2

spas

tici

ty;

wal

kin

gw

ith

sup

po

rt

12

65

Mal

eB

ack

pai

n,

par

apar

esis

,G

rad

eB

D1

1-D

12

Min

i-th

ora

coto

my

,d

eco

mp

ress

ion

,fu

sio

n

wit

hil

iac

cres

tg

raft

,an

dP

CS

fix

atio

n

15

Imp

rov

ed;

no

defi

cits

,

Gra

de

E

*A

mer

ican

Sp

inal

Inju

ryA

sso

ciat

ion

gra

de

for

neu

rolo

gic

defi

cit

(Gra

de

A–

E);

�N

uri

ck’s

gra

de

for

spas

tici

ty(G

rad

e0

–5

);D

LT

=d

ors

ola

tera

lth

ora

coto

my

;R

Pl

=re

tro

ple

ura

lap

pro

ach

;

PC

S=

per

cuta

neo

us

tran

sped

icu

lar

scre

w;

MIS

=m

inim

ally

inv

asiv

esu

rger

y.


123

acid-fast bacillus staining, bacterial culture to rule out

secondary infection of cold abscess, and BactecTM culture

(Becton Dickinson and Co, Franklin Lakes, NJ, USA) for

Mycobacterium tuberculosis.

Four patients were on ATT for 1 to 3 months before

surgery. They underwent surgical intervention with onset

of neurologic deficits. The mean duration of ATT was

13.1 months. All patients had resolution of the disease on

MRI after which ATT was stopped.

Surgical Approaches

The patients were divided into two groups based on MIS

approach: (1) the posterior-only group (n = 10; one lost to

followup) (Table 1) and (2) the hybrid group (n = 12)

(Table 2). The main criterion for choosing the type of

surgery was the extent of destruction of the vertebral body.

Patients with relatively preserved vertebral body heights

(\ 25% collapse) underwent the first procedure, an entirely

posterior approach. All of these patients had significant

epidural collection causing cord compression and neuro-

logic deficits or severe radiculopathy but no significant

vertebral body collapse to require reconstruction of the

ventral vertebral column. The primary aim was to

decompress the spinal cord to hasten neurologic recovery.

Internal fixation was performed to provide immediate sta-

bility, allow for early mobility, and avoid progression of

deformity during healing. Patients with more than 25%

collapse required ventral column reconstruction addition-

ally and underwent the second procedure.

Posterior-only MIS Technique

The posterior-only MIS technique involved MIS transpe-

dicular debridement (for the thoracic level) and MIS

hemilaminotomy and debridement (for the lumbar spine)

followed by internal fixation using percutaneous transpe-

dicular screws (Fig. 2). The patient was placed prone on

bolsters with care taken to keep the abdomen free. The

level to be decompressed was localized with a C-arm.

There were differences with respect to the procedure when

performed at the thoracic and lumbar regions.

In the thoracic region, MIS decompression was achieved

by transpedicular access. An oblique incision was placed

paramedially 2.0 to 2.5 cm from the midline. The lumbo-

dorsal fascia was incised, paraspinal muscles were split by

passing sequential dilators, and then an expandable tubular

access channel (METRxTM X-Tube; Medtronic, Inc;

25-mm diameter) was docked over the facet (Fig. 2A–B) at

that level. The facet and pedicle were drilled sequentially.

The medial and inferior margins of the pedicle were kept

intact until the end and removed once the vertebral body

was reached to avoid injury to the root and thecal sac.

C-arm images were taken intermittently to confirm the tra-

jectory. Intracorporeal and epidural decompression of the

necrotic tissue and removal of the purulent material, loose

granulation tissue, and necrotic bone fragments were per-

formed (Fig. 2C). After maximal microscopic decompression,

endoscope assistance could be used to visualize the ventral

aspect of the thecal sac directly and further debridement

continued using angled instruments (Fig. 2D–E). Adequate

decompression could thus be achieved using a combination of

the microscope and endoscope. After this, a thorough wash

was performed and the wound was closed in layers.

In the lumbar spine, a hemilaminotomy was performed

on the more symptomatic side. The ligamentum flavum

was excised, the root retracted medially, and the disc space

entered. Removal of pus, granulation tissue, and loose bone

fragments was performed.

Patients 1 and 2 underwent minimally invasive transpe-

dicular decompression only (no fixation) due to extensive

disease ([ two contiguous segments) (Fig. 3). Patients 3 to

10 underwent single-stage minimally invasive decompres-

sion and fixation. For fixation of the thoracic and

thoracolumbar spine, the Longitude1 System (Medtronic,

Inc) was used (Figs. 4, 5), and for fixation of the lumbar

spine, the Sextant1 System (Medtronic, Inc) was used

(Fig. 6). Implant removal was planned in patients with fix-

ation at the dorsolumbar and lumbar levels in the presence of

radiographic or clinical evidence of implant fatigue.

Hybrid MIS Technique

The hybrid MIS technique involved ventral decompression

and fusion performed in the lateral position by the trans-

thoracic route (using two options: (1) dorsolateral

thoracotomy and the extrapleural approach or (2) mini-

thoracotomy [mini-open or using tubular retractor system]

and the transpleural approach), drainage of abscess,

debridement of granulation tissue and necrotic bone to

achieve adequate cord decompression, ventral column

reconstruction using iliac crest or rib autograft or titanium

cage filled with autograft, and posterior fixation using

percutaneous transpedicular screws in the same sitting

(Fig. 7). The dorsolateral extrapleural approach was used

more often in the lower dorsal spine and in the earlier part

of the surgical series. With the availability of expanding

tubular retractors with longer blades (MarsTM 3 V System;

Globus Medical, Inc, Audubon, PA, USA; and the Direct

Lateral Interbody Fusion1 System; Medtronic, Inc), these

were used more often for performing mini-thoracotomy

later in the series (Figs. 7, 8). Decompression included

corpectomy or conservative intracorporeal debridement of


123

necrotic bone until healthy bone margins were encoun-

tered. This was supplemented with posterior fixation with

posterior transpedicular screws inserted percutaneously in

the prone position in the same sitting as a single stage.

Outcomes

The patients were evaluated clinically once a month until

healing of the disease. A plain radiograph was taken at

6 weeks, 6 months, and 12 months after surgery. MRI scan

was done at 3 months to assess the response to ATT and at

12 months to assess healing. Subsequently, the patients

were asked to visit the outpatient clinic (by telephone call

or letter) and plain radiographs of the spine were taken. At

the followup clinical evaluations, the treating surgeon (NG)

assessed neurologic recovery using ASIA grading [4] for

neurologic function and Nurick’s score [19] for myelopa-

thy. Deformity progression, fusion, and implant fatigue

were monitored on the spine radiographs. To assess

deformity, a radiologist (RV) measured Cobb’s angle in the

sagittal plane on plain radiographs as the angle between the

superior endplate of the uppermost affected vertebrae and

inferior endplate of the lowermost involved vertebral body.

No intraobserver reliability testing was performed. In

addition, the treating surgeon (NG) performed a chart

review to identify and document reoperations and com-

plications, including procedure-related complications, such

as wound infections and pulmonary complications, after

surgery.

Results

All patients showed neurologic improvement from one to

three grades: 33% improved one grade, 53% two grades,

and 13% three grades (Table 3). In the posterior-only

group (Table 1), five of six patients with thoracic tuber-

culosis presented with neurologic deficits preoperatively

(four ASIA Grade C, one Grade D). At followup, all

improved to Grade E with no residual motor deficits. Three

of these five patients had residual spasticity (Nurick’s

Grade 2) at followup. In the hybrid group (Table 2), of the

10 patients who presented with neurologic deficits, two had

ASIA Grade B deficits, four Grade C, and four Grade D. At

followup, all improved to Grade E with no deficits. One

patient had residual spasticity (Nurick’s Grade 2). There

were no cases of deterioration in neurologic function.

Fig. 2A–F MIS transpedicular decompression and percutaneous fix-

ation (posterior-only MIS method) are illustrated. (A) The X-Tube is

positioned. (B) The position of the X-Tube is confirmed with the C-arm.

(C) An intraoperative microscopic view after decompression of the

thecal sac is shown. (D) An endoscopic view allows better visualization

of the ventrolateral aspect of the dura using the 30� forward-angled 4-

mm telescope. Asterisk = thecal sac. (E) Endoscope-assisted decom-

pression of the ventral aspect of the thecal sac is performed using an

angled curette. Arrow = necrotic bone. (F) A C-arm image shows the

extent of decompression with angled curettes.


123

Preoperative, immediately postoperative, and last fol-

lowup Cobb’s angles for each patient in both groups are

shown (Table 4). In the posterior-only group, the mean ±

SD preoperative kyphotic angle was 13.3� ± 4.3� in thoracic

spine and 32.8� ± 2.8� in the lumbar spine. Immediately

postoperatively, these angles improved to 10.8� ± 2.8� and

24.3� ± 10�, representing mean corrections of 2.5� (18.9%

correction) and 8.5� (24.4% correction) in the thoracic and

lumbar spines, respectively. At last followup, these angles

were 12.8� and 27�, representing mean losses of 2� and 2.7�in the thoracic and lumbar spine, respectively. In none of the

eight patients who underwent fixation were the postopera-

tive Cobb’s angles more than preoperative angles. In the

two patients who underwent decompression only without

fixation, these values were 11.5� preoperatively, 12.5�postoperatively, and 14.5� at last followup, with progression

of deformity. In the hybrid group, the mean preoperative

Cobb’s angle was 19.8� (range, 5�–50�), which was cor-

rected to 15.6� (range, 7�–44�) immediately postoperatively,

with a mean correction of 4.2� (21% correction). At last

followup, the angle was 17.3�, with a mean correction loss of

1.6� (10.5%).

Complications were observed in two of 22 patients

(9%). One patient had a dural tear requiring patch repair

and cerebrospinal fluid diversion (hybrid group, Patient

11). Of a total of 76 screws placed percutaneously, one

screw breached the medial cortex causing significant

radicular pain without deficit (right L5; posterior-only

group, Patient 9). This screw had to be repositioned during

another surgical procedure; this has been the only reoper-

ation in this series to date. There were no significant

approach-related complications in either group. The elderly

patients tolerated these procedures well, with no significant

pulmonary complications. No evidence of implant fatigue,

pullout, or breakage was noticed in any patient at latest

followup. Though removal of screws was planned after

healing in the posterior-only group, none of these patients

have clinical or radiographic evidence of implant failure.

The screws have therefore not been removed.

Discussion

Tuberculosis of the spine is a common site of extraskeletal

tuberculosis. Depending on the level and extent of the

disease, it can cause back pain, deformity of the spine, and

neurologic deficits. As the disease primarily involves ver-

tebral bodies, conventional exposures to the ventral aspect

of the thoracic and lumbar spine are extensive, with their

attendant morbidities, and may be poorly tolerated by these

patients [15]. MIS techniques are being applied to treat

such spinal disorders as trauma, tumors, and deformity [2,

3, 16, 21, 28] with good results. We therefore evaluated (1)

neurologic results, (2) radiographic results, and (3) com-

plications associated with either a posterior-only MIS

approach or a hybrid MIS approach in patients with

tuberculosis of the thoracic and lumbar spine.

For those requiring ventral column reconstruction,

VATS has been used as a MIS technique for biopsy and

decompression alone [10, 12, 15] or in combination with

percutaneous posterior transpedicular fixation [11, 24].

However, there are some limitations to this technique [11,

15]. It requires additional equipment, dedicated long

instruments, a steep learning curve, a two-dimensional

view, hemodynamic alterations due to collapse of the lung,

pleural adhesions limiting this approach, and significant

pulmonary complications [15]. Mini-thoracotomy (mini-

open or using tubular retractor ports) on the other hand

overcomes all these limitation in addition to being familiar

to spine surgeons because the anatomic landmarks are

similar to those used in conventional approaches. Com-

bined with percutaneous transpedicular fixation, this hybrid

MIS method helps to achieve all the aims of conventional

approaches using MIS principles.

In a subgroup of patients with focal peridiscal involve-

ment and relatively preserved vertebral body height but

with significant neurologic deficits due to epidural com-

pression, conventional approaches may be considered an

Fig. 3A–B Preoperative MR images show the spine of Patient 2

(posterior-only group) who underwent MIS decompression only. (A)

A T1-weighted sagittal image with contrast shows extensive multi-

level involvement of the spine. (B) A T1-weighted axial image shows

epidural granulation and cord compression.


123

overtreatment. Keeping these patients on ATT medications

without offering surgery may result in poor neurologic

outcomes [7], delayed or incomplete neurologic recovery,

and progression of deformity, causing significant pain and

delayed neurologic deterioration [8, 29, 31]. Other MIS

techniques such as nucleotome-based percutaneous aspi-

ration [5, 32], endoscopic suction and drainage [6], and

open transpedicular decompression [1] have also been

described for infective spondylodiscitis. These have been

used predominantly for evacuation of the pus and their

utility is limited in those with thicker pus or granulation

tissue. Lee et al. [13] described conventional posterior

transpedicular curettage and decompression augmented

with transpedicular screws in adjacent healthy vertebrae for

similar patients with preserved vertebral body heights.

Kandwal et al. [11] used transforaminal access using MIS

methods in lumbar vertebral bodies. The posterior-only

MIS approach as described in this series is feasible in

Fig. 4A–F Images illustrate the

case of Patient 6 (posterior-only

group). Preoperative T2-weight-

ed (A) sagittal and (B) axial MR

images show epidural and para-

vertebral abscess and granulation

with cord compression and cord

edema. Preoperative (C) sagittal

and (D) axial CT scans show

the extent of vertebral body

destruction and necrotic bone.

Postoperative (E) sagittal and (F)

axial CT scans show the extent of

bony removal and canal decom-

pression achieved.

Fig. 5A–C Followup images

are shown for the patient in

Figure 4 (Patient 6). (A) A T2-

weighted sagittal MR image

shows healed tuberculosis. (B)

Sagittal and (C) AP CT scans

show no deformity progression.


123

patients with both thoracic and lumbar tuberculosis, with

good neurologic recovery and nonprogression of

deformity.

Good neurologic recovery is achieved using either

conventional methods irrespective of ventral or dorsal

approaches for decompression [22, 23] or using MIS

methods such as VATS [10, 11, 15]. Similar results were

observed in our study. Decompression using MIS methods

is sufficient to achieve good neurologic outcomes.

Spinal deformity is a dreaded complication occurring

during the active healing phase and after healing in those

with severe deformity [9]. In our posterior-only group,

there was only 2� loss of correction over 30 months of

followup. This was much less than an increase of 6� to 15�

Fig. 6A–E Images illustrate the case of Patient 9 (posterior-only

group). Preoperative T1-weighted (A) sagittal and (B) axial MR

images with contrast show significant epidural and paravertebral

abscess and psoas collection. Photographs show the incisions (C)

before and (D) after healing. (E) A lateral followup radiograph shows

preserved spinal alignment at the healed stage.

Fig. 7A–D Intraoperative images

illustrate mini-thoracotomy with

expandable tubular retractors. (A)

A three-blade retractor is positioned,

with one blade retracting the lung.

(B) Paravertebral pus is drained.

(C) A defect (arrow) remains after

debridement. (D) Fusion is per-

formed with iliac crest autograft

(arrow).


123

in kyphosis seen in those treated nonoperatively [1, 17]. The

deformity progression in the first two patients of posterior-

only group were comparable to those with surgical decom-

pression only [7, 9, 17, 20]. Due to the relatively preserved

vertebral body height, spontaneous fusion is expected to

occur in these patients after healing and internal fixation

helped to avoid deformity progression in this subgroup of

patients till healing occurred. Ringel et al. [24] treated 15

patients with infective spondylodiscitis of the thoracic and

lumbar spine with transpedicular fixation and antibiotics

only. These patients were not fit to undergo a second-stage

ventral procedure. Lee et al. [13] performed drainage and

curettage and fixation without interbody fusion in 10 patients

with infective lumbar spondylodiscitis. All patients achieved

fusion. Posterior transpedicular fixation is better in correct-

ing and maintaining deformity [14, 22]. Percutaneous

methods achieve this aim with minimal dissection and tissue

disruption. In two studies by Lee et al. [14] and Pu et al. [22]

using conventional methods of posterior transpedicular

decompression and fixation, mean preoperative kyphosis

ranged from 18� to 24�. This was corrected by 4� to 8�, with

a 6� loss of correction over a mean followup of 22.5 months

[22]. These modest corrections were similar to our posterior-

only group. Patients with deformities between 16� and 40�treated by ventral debridement and posterior instrumentation

using either conventional or VATS methods achieved 8� to

21� correction in deformity, with losses of 4� to 5� [9, 11,

22]. In our hybrid group, the mean preoperative kyphosis was

19.8�, with a 4� correction achieved postoperatively and a

1.6� loss of correction at last followup. Though there has

been some loss of correction in both of our groups, this was

mild and may not affect fusion. Upadhaya et al. [31] and Jain

et al. [9] showed that the deformity does not progress once

healing of tuberculosis occurs. With minimum followup of

15 months and healed tuberculosis in all, further progression

of deformity is not expected in our group of patients.

Complications were observed in only 9% of patients.

This is significantly less than the 24% to 31% rates

reported using conventional approaches [15, 22, 25]. Even

MIS methods such as VATS have significant risk of pul-

monary complications [10, 11, 15].

Implant removal remains controversial in those who

undergo fixation without fusion, as it requires second sur-

gery and general anesthesia. Studies done by De Iure [3]

and Court and Vincent [2] on patients with spinal fractures

treated by percutaneous transpedicular fixation methods

show that the need for implant removal may be low, as few

patients have clinical or radiographic evidence of failure.

Infective pathologies may behave differently, as fusions

between involved bodies occur in them. Lee et al. [13] did

not remove screws in any of their 10 patients with infective

spondylodiscitis at a mean followup of 29 months (maxi-

mum, 61 months), although they noticed screw loosening

Table 3. Neurologic outcomes (n = 15 patients)

Group American Spinal Injury Association grade

(number of patients)

Preoperative Postoperative Followup

Posterior-only (n = 5) C (4) D (4) E (5)

D (1) E (1)

Hybrid (n = 10) B (2) C (2) E (10)

C (4) D (6)

D (4) E (2)

Fig. 8A–E Images illustrate the case of Patient 9 (hybrid group). (A) A

preoperative T2-weighted sagittal MR image shows destruction of

vertebral body, kyphosis, and epidural and paravertebral abscess

with cord compression. (B) A preoperative sagittal CT scan shows

sequestered bone compromising the canal. Postoperative (C) AP and

(D) sagittal CT scans show the spine after intracorporeal decompression

and iliac crest graft in situ and correction of deformity. (E) A lateral

followup radiograph shows bony fusion without deformity progression.


123

in three patients. None of our patients with a mean fol-

lowup of 30 months (maximum, 59 months) had any

evidence of implant fatigue. Screws have not been removed

in any of our patients.

This study had a number of limitations. First, there is no

comparison group between the conventional and MIS

procedures. Thus, it is difficult to quantify the difference in

efficacy between MIS procedures and conventional ones.

Second is the short-term followup with no formal assess-

ment of fusion. We used no standardized outcome scores

for pain or function so we cannot be sure whether our MIS

approaches are any easier on patients than traditional

approaches. Our deformity corrections were modest, with

no intraobserver reliability tests performed. Finally, the

MIS approaches cannot be applied universally and selec-

tion criteria should be laid down depending on the level of

the disease and the available expertise and instrumentation.

In conclusion, this study demonstrated that MIS tech-

niques can be used appropriately to treat patients with

tuberculosis of the thoracic and lumbar spine, with good

neurologic recovery, avoidance of deformity progression,

and few complications. Properly designed studies are needed

to compare the MIS approaches with open approaches with

respect to different end points.

References

1. Chacko AG, Moorthy RK, Chandy MJ. The trans-pedicular

approach in the management of thoracic spine tuberculosis: a

short term follow up study. Spine (Phila Pa 1976). 2004;29:

E363–E567.

2. Court C, Vincent C. Percutaneous fixation of thoracolumbar

fractures: current concepts. Orthop Traumatol Surg Res. 2012;98:

900–909.

3. De Iure F, Cappuccio M, Paderni S, Bosco G, Amendola L.

Minimally invasive percutaneous fixation of thoracic and lumbar

spine fractures. Min Invasive Surg. 2012;2012:141032

4. El Masry WS, Tsubo M, Katoh S, El Miliqui YH, Khan A.

Validation of the American Spinal Injury Association (ASIA)

motor score and the National Acute Spinal Cord Injury Study

(NASCIS) motor score. Spine (Phila Pa 1976). 1996;21:614–619.

5. Hanaoka N, Kawasaki Y, Sakai T, Nakamura T, Nanamori K,

Nakamura E, Uchida K, Yamada H. Percutaneous drainage and

continuous irrigation in patients with severe pyogenic spondylitis,

Table 4. Radiographic outcomes

Patient Level Cobb’s angle (�) Followup (months)

Preoperative Postoperative Followup

Posterior-only group

1 D11-L1 13 14 18 53

2 D7-D8, D10-L2 10 11 11 3

3 D11-D12 9 8 9 55

4 D11-D12 13 9 12 47

5 D9-D10 14 12 13 25

6 D8-D9 17 14 17 29

7 L4-L5 35 24 26 59

8 L3-L4 30 14 18 52

9 L4-L5 33 29 32 44

10 L1-L2 33 30 32 15

Hybrid group

1 D10-D11 20 14 19 48

2 D10-D11 38 28 30 40

3 D10 8 7 8 26

4 D10-D11 16 14 14 22

5 D11-D12 50 44 45 20

6 D9-D10 18 10 13 18

7 L2-L3 25 12 15 18

8 D10-D11 15 12 13 18

9 D9-D10 20 13 15 17

10 D8-D10 5 10 11 17

11 D7-D8 13 10 11 16

12 D11-D12 15 10 11 15


123

abscess formation and marked bone destruction. J Neurosurg

Spine. 2006;4:374–379.

6. Ito M, Sudo H, Abumi K, Kotani Y, Takahata M, Fujita M,

Minami A. Minimally invasive surgical treatment for tuberculous

spondylodiscitis. Minim Invasive Neurosurg. 2009;52:250–253.

7. Jain AK. Treatment of tuberculosis of the spine with neurological

complications. Clin Orthop Relat Res. 2002;398:75–84.

8. Jain AK. Tuberculosis of the spine: a fresh look at an old disease.

J Bone Joint Surg Br. 2010;92:905–913.

9. Jain AK, Dhammi IK, Jain S, Mishra P. Kyphosis in spinal tubercu-

losis-prevention and correction. Indian J Orthop. 2010;44:127–136.

10. Jayaswal A, Upendra B, Ahmed A, Chowdhury B, Kumar A.

Video assisted thoracoscopic anterior surgery for tuberculous

spondylitis. Clin Orthop Relat Res. 2007;460:100–107.

11. Kandwal P, Garg B, Upendra BN, Chowdhury B, Jayaswal A.

Outcome of minimally invasive surgery in the management of

tuberculous spondylitis. Indian J Orthop. 2012;46:159–164.

12. Kapoor SK, Kapoor S, Agarwal M, Aggarwal P, Jain BK Jr.

Thoracoscopic decompression in Pott’s spine and its long term

follow up. Int Orthop. 2012;36:331–337.

13. Lee BH, Lee HM, Kim TH, Kim HS, Moon ES, Park JO, Chong

HS, Moon SH. Transpedicular curettage and drainage of infective

lumbar spondylodiscitis: technique and clinical results. Clin Or-

thop Surg. 2012;4:200–208.

14. Lee SH, Sung JK, Park YM. Single-stage transpedicular

decompression and posterior instrumentation in treatment of

thoracic and thoracolumbar spinal tuberculosis: a retrospective

case series. J Spinal Disord Tech. 2006;19:595–602.

15. Lu G, Wang B, Li J, Liu W, Cheng I. Anterior debridement and

reconstruction via thoracoscopy assisted mini-open approach for

the treatment of thoracic spinal tuberculosis: minimum 5 year

follow up. Eur Spine J. 2012;21:463–469.

16. McLain RF. Spinal cord decompression: an endoscopically assisted

approach for metastatic tumors. Spinal Cord. 2001;39:482–487.

17. Medical Research Council. A 15 year assessment of controlled

trials of the management of tuberculosis of the spine in Korea and

Hong Kong. J Bone Joint Surg Br. 1998;80:456–462.

18. Moon MS. Tuberculosis of the spine: controversies and a new

challenge. Spine (Phila Pa 1976). 1997;22:1791–1797.

19. Nurick S, The pathogenesis of the spinal cord disorder associated

with cervical spondylosis. Brain. 1972;95:87–100.

20. Okada Y, Miyamoto H, Uno K, Sumi M. Clinical and radiolog-

ical outcome of surgery for pyogenic and tuberculous spondylitis:

comparisons of surgical technique and disease type. J Neurosurg

Spine. 2009;11:620–627.

21. Palmisani M, Gasbarrini A, Brodano GB, De Iure F, Cappuccio

M, Boriani L, Amendola L, Boriani S. Minimally invasive per-

cutaneous fixation in the treatment of thoracic and lumbar spine

fractures. Eur Spine J. 2009;18(suppl 1):S71–S74.

22. Pu X, Zhou Q, He Q, Dai F, Xu J, Zhang Z, Branko K. A

posterior versus anterior surgical approach in combination with

debridement, interbody autografting and instrumentation for

thoracic and lumbar tuberculosis. Int Orthop. 2012;36:307–313.

23. Rasouli MR, Mirkoohi M, Vaccaro AR, Yarandi KK, Movaghar

VR. Spinal tuberculosis: diagnosis and management. Asian Spine

J. 2012;6:294–308.

24. Ringel F, Stoffel M, Stuer C, Meyer B. Minimally invasive

transmuscular pedicle screw fixation of the thoracic and lumbar

spine. Neurosurgery. 2006;59(4 suppl):361–367.

25. Sharkawi MM, Said GK. Instrumented circumferential fusion for

tuberculosis of the dorso-lumbar spine: a single or double stage

procedure? Int Orthop. 2012;36:315–324.

26. Smith JS, Ogden AT, Fessler RG. Minimally invasive posterior

thoracic fusion. Neurosurg Focus. 2008;25:E1–E9.27. Soundararaj GD. Simultaneous anterior decompression and pos-

terior instrumentation of the tuberculous spine using anterolateral

extrapleural approach. J Bone Joint Surg Br. 2009;91:702–703.

28. St Clair SF, McLain RF. Posterolateral spinal cord decompres-

sion in patients with metastasis: an endoscope assisted approach.

Surg Technol Int. 2006;15:257–263.

29. Tuli SM. Severe kyphotic deformity in tuberculosis of the spine.

Int Orthop. 1995;19:327–331.

30. Tuli SM. Tuberculosis of the spine: a historical review. Clin

Orthop Relat Res. 2007;460:29–38.

31. Upadhyay SS, Saji MJ, Sell P, Sell B, Yau AC. Longitudinal

changes in spinal deformity after anterior spinal surgery for

tuberculosis of the spine in adults; a comparative analysis

between radical and debridement surgery. Spine (Phila Pa 1976).

1994;19:542–549.

32. Yu MY, Siu C, Wing PC, Schweigel IF, Jetha N. Percutaneous

suction aspiration for osteomyelitis: report of two cases. Spine

(Phila Pa 1976). 1991;16:198–202.


123

Documents

Minimally Invasive Surgical Approaches in the Management of Tuberculosis of the Thoracic and Lumbar Spine