Treatment of Lumbo-sacral
steno-instability
(esperienza col sistema
interspinoso BacJac)
Dott. RAFFAELE MANGIALARDI
raffaele.mangialardi@tin.it
(CBH Bari - S. Camillo Taranto)
VERTEBRAL STENOSIS
It is a pathological narrowing of the neural
channel and/ or the conjugation foramen
(caused by bone, arthrosis, and joint
changes with:
COMPRESSION
OF THE NERVOUS
STRUCTURES.
Two biomechanical types of
stenosis:
-Dynamic stenosis (manifests
itself at spine movements)
-Fixed stenosis (in advanced
stage)
DYNAMIC STENOSIS
INSTABILITY PHASE with
SPINAL FIXED STENOSIS
As the degeneration
progresses, it becomes a
fixed stenosis.

The dimensions of the
central and lateral
channels reduce because
of facet hypertrophy,
thickening of yellow
ligaments with their
bulging in the channel.

MECHANICAL PRESSURE on the
SPINAL NEUROSTENOSIS
STRUCTURES
Mechanical
irritation
(traction
compression)
Chemical irritation
(nucleus)
Intra-neural inflammation
(ischemia, edema, demyelinization)
Functional alterations
Lost nervous function
Hyperexcitability (pain)
(generation of ectopic
impulses)
Establishing of causes and areas of the
DEGENERATIVE STENOSIS
No
We should consider further anatomic
pathological conditions!!!
…Clinical recovery becomes impossible.
Advanced degenerative changes
Severe degenerative disc disease at L5-S1
Severe STENOSIS
Stenosis at L4-5
Severe STENOSIS
Severe STENOSIS
Impact of stenosis on nervous and vascular structures
TREATMENT OPTIONS
DEPENDING ON THE CASE:
1) Conservative treatment
2) “Major” SURGICAL TREATMENT
Between the two:
Use of
INTERSPINOUS IMPLANTS
CONSERVATIVE
TREATMENTS
Peri-epidural infiltrations
NSAID
Calcitonin
Long-term bed rest
Physical therapy (Magnetotherapy, Ionophoresis, TENS,
etc)
Kineti therapy(postural training, swimming, etc..)
Corseta and orthoses
“Major” surgical treatments
Laminectomy or Laminotomy
Laminectomy and/ or foraminotomy
Laminectomy + foraminotomy
completed by partial arthrectomy plus
fusion (in case of severe instability)
with intersomatic arthrodesis (screws,
plates)
Difference between interspinous
surgery versus laminectomy
Incision
4-6 cm
10-13 cm
Surgery
above the lamina
under the lamina
EBL
0 cc
few, but present
Surgery time
40-60 min
120-150 min
Complications
3,3 %
9,7 %
Patient is soon able to stand
bed rest: minimum 2-3 days
Return to activity 7-10 days
after approximately 30 days
Patient favors this treatment
Patient does not favor this treatment
Why an interspinous
intervention is performed
The idea of a device positioned between the
spinous
processes
in
order
to
improve
symptomatology of the lumbar stenosis, it stems
out of a simple clinical observation:
The patients’ symptoms improve while flexion of
the spine and they become worse while they
hyperextend it:
This is where comes the idea of an implant,
which would limit the extension, at the same
time
restricting
the
channel
and
lateral
formamina, to be inserted during
a mini-invasive intervention.
Why Interspinous Decompression
CLINICAL MOTIVATIONS
The symptoms worsen at spine
extension and subside in flexion.
The patients are feeling better while
seated with upper limbs on a table in
orthostatic position in slight flexion
Why Interspinous Decompression
Biomechanical studies confirm the effect:
• The in situ load on spinous
processes is only 12 – 16%
• The implant, inserted into the
interspinous space, remains very
stable.
Why Interspinous Decompression
ANATOMICAL MOTIVATION
The following happens during extension
of the spine:
1) Worsening of the bulging disc
2) Worsening of the recess stenosis
3) Worsening of the minimal listhesis
4) Worsening of local lack of stability
Why Interspinous Decompression
Dynamic Tests
Revealed that the interspinous
device
Limits extension of the affected
area and does not limit the axial
rotation and the lateral movement
of the spine.
Why Interspinous Decompression
Studies of the therapeutic
mechanism revealed that:
– In extension, the channel
area, its diameter and subjoint diameter increased by:
18%,10%,48%
– The foraminal area and the
linear surfca increased,
respectively, by 25% and
41%
Why Interspinous Decompression
Pressure on the disc and load on the facet
joints diminish at the treated level.
In extension, the pressure on the posterior
part of the anulus diminish by 63%
The pressure in the nucleus diminishes by
41%
The pressure on the facet diminishes by 58%
There are no pressure changes in the levels
adjacent to the treated one.
PATHOLOGIES TREATABLE with
interspinous devices
•
•
•
•
•
•
•
•
•
•
•
Lumbar spinal stenosis
Degenerative spondylolisthesis (up to Grade I)
Baastrups’ syndrome
Disc degeneration (also post-operative)
Instability and facet syndromes
Modic I degeneration, associated with stenosis
Disc protrusion, associated with stenosis and recess
stenosis
Lumbar pain induced by axial load
Disc unloading, adjacent to the arthrodesis site
Post-discectomy disc assistance
Internal lesion of the disc
CONTRAINDICATIONS
Scoliosis greater than 25° (Cobb)
Cauda equina syndrome
Isthmic spondylolisthesis
Pthological or multiple vertebral fractures
Severe obesitas
Paget disaese or vertebral metastases
Active infection
Anatomic conditions that do not allow for a
stable implantation of the device.
New interspinous approach
The B A C J A C
Following test using other
interspinous devices, which are
still ongoing, we started using
the BacJac.
The BacJac
KINEMATICS OF BACJAC
Reduces the extension of the treated
are in flexion-extension
Maintains the range of motion in
rotation and lateral bending
Does not have any impact on the
range of motion of the adjacent
segments.
Indications for BacJac
Intermittent neurogenic claudication (INC)
Spondylolisthesis up to grade 1.5 (out of 4,
approximately 35%) with INC
Baastrup syndrome/ Disc lowering
Back pain caused by axial load
Facet syndrome
Degenerative and/ or iatrogenic disc syndrome
Contained herniation of the nucleus
Shift of disc adjacent to lumbar arthrodesis
BacJac impact on the canal
dimensions
In extension, it decompresses the nervous
structures at the treated level, increasing
 Spinal canal area by 18%;
 Diameter of the spinal canal by9%;
 Sub-articular diameter by 50%;
 Foraminal area by 25%;
 Foramen width by 41%.
There is no impact on the adjacent levels.
BacJac : Action on the disc
pressure
In extension, it reduces the pressure of
the posterior anulus by 63% and of the
nucleus by 41%
Does not increase pressure on the
adjacent discs.
BacJac: Impact on the disc height
It increase the posterior height of
the vertebral disc
(at the level of the implant)
by 1,5 mm
BacJac: Pressure on the
adjacent facet
In extension, at the implant level, it
reduces the pressure on the articular
facets by 61%.
It does not increase the pressure on
the facet of the adjacent segments.
BacJac: sagittal balance
In neutral position, implants at 1 level
or 2 levels, do not change the lumbar
curvature, considering the initial
pathological curve.
Indications/ contraindications for
BacJac
Indications:
– Motor deficit
– Lumbar instability
– Previous spine
surgery
Contraindications:
– Major low back
pain
– Symptoms that
increase in flexion
Surgery details
Vertical incision of 3 m, at 1 cm from the
median line.
No supraspinal ligament damage.
At BacJac insertion, remove any anatomic
obstacles (such as hypertrophic facets).
BacJac instruments
Small dilator (5 mm)
Big dilator (8 mm)
Interspinous divaricator and sizer
BacJac inserter with pusher
Removal tool
BacJac characteristics
Load resistant
Biocompatibility
No MRI and CT artifacts
Large contact area
Minimal risk of dislocation
Biomechanical modules similar to physiological
ones
BacJac characteristics
Unilateral approach
Preservation of ligaments
Minimal invasive
It “positions itself” suring insertion
Surgical Technique(BacJac)
Lateral or knee-pectoral decubitus
Adjusts to the space (lateral X-ray)
General, local or peridural anaesthesia
Median incision of approximately 3 – 5 cm
Partial exposure of the lamina, only on one side, exposure of
interspinous ligament.
Perforate the interspinous ligament, leaving intact the supraspinal
ligament (this way avoiding any possible dislocation of the prosthesis)
Post operative
Each surgeon follows his own post-op routines,
based on age and general conditions.
Generally: The patient returns to his activities
WHEN HE CAN TOLERATE THEM.
For 6 weeks: Do not lift weights.
After 20 days: Muscle strengthening exercises,
if tolerated.
Personal cases
Usage of inclusion and exclusion criteria.
Clinical examination.
Instrument-assisted examinations: X-Rays
(standard and dynamic)MRI, CT, EMG.
Clinical study:
Inclusion criteria
Clinical and radiological inclusion criteria:
Patients with pain in the lower limbs, gluteus, inguinal pain,
with or without lumbar pain.
In order to qualify for the study, the patients must be able to sit
for 50 minutes without pain, walk for 50 minutes without pain,
and have followed conservative treatment for six months.
The diagnosis of spinal stenosis (LSS) or lateral stenosis must be
confirmed using CT or MRI at 1 or 2 levels.
Clinical Study:
Exclusion Criteria
Clinical and radiological exclusion criteria:
Permanent neurological deficit
Cauda equina syndrome
Major lumbar instability following a previous surgical intervention
Major peripheral neuropathy or acute secondary and radicular enervation
Spondylolisthesis at more than 1.5 (on a scel from 1 to 4)
Systemic infections
Paget disease
Contraindiations BacJac
Constant pain, not related to the dorsal spine position
Cauda equina syndrome caused by neural compression, which causes
neurogenic intestinal dysfunction (fecal incontinence) or neurogenic urinary
dysfunction (urinary retention or incontinence)
Major scoliosis(Cobb angle of more than 25°)
Isthmic or degenerative spondylolisthesis at the level exceeding 1.5 (on a scale
from 1 to 4) at the affected level
Pathological or multiple fractures of vertebra and/ or hips
Contraindications BacJac
Obesity (with the body mass index exceeding 40 kg/ m2);
Paget disease of the affected segment or vertebral metastases
Active infection
Abnormal spinal anatomy, which would prevent from implanting of the
device, or anatomy that would cause lack of implant’s stability follwoing
the implant
Personal cases
Average age:
Levels:
Pathologies:
Single level:
Double level:
58 years
L2-3, L3-4, L4-5, L5-S1
steno-instability, facet stenosis
60 % of cases
40 % of cases
Implants (status October 2008): 60
Pre-op MRI: Stenosis, especially at L4-5
Post-op X-ray with 2 BacJacs
Results
70% :
Improvementas of the first post-op day (the
patients can even sleep in prone position,
increased walking autonomy, etc).
20%: Partial, but fast improvements
* As of now: no patient underwent subsequent surgery
(in order to repair the supraspinal ligament or for
posterior dislocation of BacJac, or for a subsequent
decompression laminectomy).
10%: There is no improvement, but no subsequent
surgeries either.
Results
All patients could stand the day following the
surgery (and in 25 cases, the evening of the
surgery).
Most of the patients (following a control X-ray of
the L-S spine in orthostatic position with AP and LL
projections) were dsicharged home before the
scheduled time (maximal stay: 3 days).
CONCLUSIONS REGARDING THE USE OF BACJAC
“Minimal” surgical intervention, which is simple and efficient, indicated
for patient suffering from claudication secondary to the lumbar canal
and/ or conjugation foraminal stenosis.
Valid alternative to the traditional surgical treatment.
Preserves the anatomical structures.
Does not change the situation of the metamers above and below the
treated area.
CONCLUSIONS REGARDING THE USE OF
BACJAC
It is a rigid interspinous device, which limits extension of the spine.
It does not limit the axial rotation and antero-lateral flexion.
It decreases the pressure on the disc and the articular facet and
increase the foramina at the affected area.
The insertion of the device does not modify the conditions at the
adjacent metamers, located above and below.
Please do not
hesitate to
contact us for
further
information
raffaele.mangialardi@tin.it