Synthes USS II Polyaxial User manual

USS II Polyaxial. The Versatile Polyaxial
Solution for the Universal Spine Systems.
Technique Guide
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Synthes USS II Polyaxial Technique Guide
Contents
Image intensifier control
Warning
This description is not sufficient for immediate application of
the instrumentation. Instruction by a surgeon experienced in
handling this instrumentation is highly recommended.
AO/ASIF Principles of Internal Fixation 4
Indications and Contraindications 5
Implants 6
Instruments 7
Surgical Technique 10
Dismantling Instructions 19
Bibliography 24
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USS II Polyaxial. The Versatile Polyaxial
Solution for the Universal Spine Systems.
USS II Polyaxial combined with USS II Ilio-Sa-
cral enables a construction to be fabricated
from the thoracolumbar spine to the pelvis.
It is suitable for the treatment of degenera-
4.2 5.2 6.2 7.0 8.0 6.2 7.0 8.0
tive diseases as well as for correcting defor-
mities. The implants are compatible with all
5 mm and 6 mm rod systems.
USS II Polyaxial
– Versatile
– Polyaxial
– Low Profile
First the screws are inserted and
then the polyaxial heads are clicked on
the screw. This enables free screw
placement.
Using the remobilization instrument
the polyaxial heads can be remobilized
even with the rod in place.
Easy handling
Pedicle screws
Cancellous
bone screws
USS II nut
Sleeve
3-D head
– Click-on head for various
combinations
– Side opening for 5 mm or 6 mm rods
– 25° deflection
Dual-core pedicle and cancellous
bone screws
– Various diameters and lengths
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AO/ASIF Principles of Internal Fixation
AO/ASIF Principles of internal fixation
In 1958 the Association for the Study of Internal Fixation
AO/ASIF formulated four basic principles which have become
the guidelines for internal fixation.
They are:
– Anatomic reduction
– Stable internal fixation
– Preservation of blood supply
– Early, active pain-free mobilization
The fundamental aims of fracture treatment are the same
for the limbs and spinal fusion. A specific goal in the spine is to
restore as much function as possible to the injured neural
elements.
AO/ASIF Principles as applied to the spine
Anatomical alignment
Restoration of normal spinal alignment to improve the
biomechanics of the spine.
Stable internal fixation
Stabilization of the spinal segment to promote bony fusion.
Preservation of blood supply
Creation of an optimal environment for fusion.
Early, pain-free mobilisation
Minimization of damage to the spinal vasculature, dura and
neural elements, which may contribute to pain reduction and
improved function for the patient.
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Indications and Contraindications
Indications
USS II Polyaxial is indicated for use in the thoracic and lumbar
spine, as well as for ilio-sacral fixations (T1–S2). It is indicated
for the posterior treatment of:
– Degenerative diseases
– Deformities in combination with USS II or USS Low Profile
pedicle screws
– Fractures and tumours with sufficient anterior support
when using USS II Polyaxial as a stand-alone device for
posterior fixation
Contraindications
– In fractures with severe anterior vertebral body disruption,
an additional anterior support or column reconstruction is
required.
Precautions
For patients with osteoporosis, the use of cancellous bone
screws is recommended.
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6Synthes USS II Polyaxial Technique Guide
Implants
The USS II Polyaxial system consists of the
following implants:
– Pedicle screws
– Cancellous bone screws
– Polyaxial 3-D heads
– Sleeves
Pedicle screws with dual core, titanium alloy (TAN)
Art. Nos. ⭋Lengths Colour
04.607.010 – 014* 4.2 mm 20 – 40 mm gold
04.607.021 – 027* 5.2 mm 25 – 55 mm purple
04.607.032 – 039* 6.2 mm 30 – 65 mm dark blue
04.607.052 – 059* 7.0 mm 30 – 65 mm green
04.607.072 – 079* 8.0 mm 30 – 65 mm pink
* All implants are also available sterile packed. Add suffix "S"
to article number.
Cancellous bone screws with dual core,
titanium alloy (TAN)
Art. Nos. ⭋Lengths Colour
04.607.232 – 239* 6.2 mm 30 – 65 mm light blue
04.607.252 – 259* 7.0 mm 30 – 65 mm turquoise
04.607.260 – 269* 7.0 mm 70 – 140 mm turquoise
04.607.272 – 279* 8.0 mm 30 – 65 mm dark blue
04.607.280 – 289* 8.0 mm 70 – 140 mm dark blue
Polyaxial 3-D heads, titanium alloy (TAN)
Art. No. For rod ⭋Colour
04.607.401* 5.0 mm light blue
04.607.402* 6.0 mm green
Sleeves, titanium alloy (TAN)
Art. No. For rod ⭋Colour
04.607.411* 5.0 mm light blue
04.607.412* 6.0 mm green
USS II nut, titanium alloy (TAN)
Art. No. Colour
499.294* green
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The basic instrument set for USS II (187.200) should be used as
basic instruments for USS II Polyaxial.
Instruments specific for USS II Polyaxial
Instruments
03.607.000 USS II Polyaxial Reamer
03.607.001 Screwdriver, bihexagonal, ⭋3.0 mm,
with T-Handle
03.607.002 Screwdriver Shaft for USS II Polyaxial cancel-
lous bone screws with lengths ≥ 70 mm
03.607.003 USS II Polyaxial Holding Sleeve for
No. 03.607.001
03.607.006 USS II Polyaxial Handle for Screw Holder
03.607.005
03.607.005 USS II Polyaxial Screw Holder
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8Synthes USS II Polyaxial Technique Guide
03.607.004 USS II Polyaxial Positioning Pliers for
3-D Heads
03.607.007 Positioner for Screw Holder 03.607.005
03.607.008 Socket Wrench, bihexagonal, ⭋11.0 mm,
self-holding, with straight handle
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03.607.009 USS II Polyaxial Rod Introduction Pliers for
Rods ⭋6.0 mm and 5.0 mm
03.607.012 USS II Polyaxial Remobilizing Instrument
03.607.013 Stop Sleeve for Remobilizing without Rod
03.607.014 Hollow Reamer ⭋12.6 mm for USS II
Polyaxial
Additional instruments
388.143 Socket Wrench ⭋5.0 mm, with T-Handle
388.502 USS Sleeve Pusher
(to be used with 03.607.009)
388.584 Socket Wrench for 12-point nut,
with L-Handle
388.615 Support for Rod Introduction Pliers
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10 Synthes USS II Polyaxial Technique Guide
Surgical Technique
1
Open pedicles and determine screw lengths
Required instruments
Pedicle Awl, length 230 mm 388.550
Pedicle Probe ⭋3.8 mm, length 230 mm 388.540
Optional instruments
Pedicle Probe ⭋4.8 mm, length 230 mm 388.539
Pedicle Probe ⭋2.8 mm, length 230 mm 388.538
Localize pedicles as described in AO ASIF Principles in Spine Sur-
gery1. With the Pedicle Awl, open the cortex of the pedicles to a
depth of 10 mm. Continue opening the pedicles using the Pedi-
cle Probe ⭋3.8 mm.
Determine the lengths of the USS II Polyaxial screws.
Note: If screws ⭋7.0 mm are implanted as the first screws, use
the Pedicle Probe ⭋4.8 mm. If screws ⭋4.2 mm are implanted
as the first screws, use the Pedicle Probe ⭋2.8 mm.
1Aebi, Thalgott, Weber
2
Insert screws into pedicles
Required instruments
Screwdriver, bihexagonal, ⭋3.0 mm, with T-Handle 03.607.001
USS II Polyaxial Holding Sleeve 03.607.003
Optional instruments
Screwdriver Shaft for USS II polyaxial cancellous bone screws
with lengths ≥ 70 mm 03.607.002
USS II Polyaxial Handle 03.607.006
Pick up the appropriate screw from the screw rack using the
Screwdriver and the Holding Sleeve. Insert the screw into the
prepared pedicle until the screw is well seated.
Note: If cancellous bone screws with a length of 70 mm or
longer are inserted, use the Screwdriver Shaft 03.607.002
attached to the USS II Polyaxial Handle.
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3
Prepare seat for 3-D heads
Required instruments
USS II Polyaxial Reamer 03.607.000
Screwdriver, bihexagonal, ⭋3.0 mm, with T-Handle 03.607.001
Apply the Reamer guided by the Screwdriver over the head of
the screw. To ensure free movement of the polyaxial 3-D head,
either ream away excessive bone or back-out the screw until the
red mark is visible.
To ream away bone, move the reamer back and forth until the
red mark on the screwdriver shaft becomes visible.
Note: Make sure that the Screwdriver is well inserted during the
procedure.
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12 Synthes USS II Polyaxial Technique Guide
4
Insert 3-D heads
Required instruments
USS II Polyaxial Screw Holder 03.607.005
USS II Polyaxial Positioning Pliers for 3-D Heads 03.607.004
Note: If more than one level has to be fused, it is recommended
to check the required curvature of the rod before inserting the
3-D heads. Do so by aligning the Rod Template (388.870, from
USS II Basic Instruments) with the screws (see step 5).
The technique of head insertion is the same no matter which
heads (for ⭋5.0 mm rods or for ⭋6.0 mm rods) are used.
Insert a Screw Holder into the appropriate 3-D head on the load-
ing station. Make sure that the red markings (flat surface of the
Screw Holder) point towards the rod-opening of the 3-D head.
Slide the Positioning Pliers over the Screw Holder, and secure
them by pulling down the plier handles. With the straight han-
dle, pick up the head and place it onto the screw.
Press the pliers to push down the locking ring over the screw
head. The 3-D head is now secured but can still be rotated in all
directions.
Note: Once the 3-D head is secured, it cannot be removed
without being destroyed.
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5
Select and insert rods
Required instruments
Holding Forceps for rod ⭋6 mm, length 290 mm 388.440
Optional instruments
Bending Pliers with Rolls for USS Rods ⭋6 mm, length 300 mm 388.960
USS II Polyaxial Handle 03.607.006
Positioner for Screw Holder 03.607.007
Determine the length and curvature of the rods. The ± 25°
polyaxial flexibility of the screw heads compensates a lateral
screw offset up to +/- 5.1 mm. If necessary, bend the rods using
the Bending Pliers.
Notes:
– Do not bend titanium rods more than 45°. Do not bend back
and forth.
– In multilevel cases, bend the rod according to the curvature of
the rod template determined in step 4.
Insert the rods with the Holding Forceps into the side-opening,
polyaxial screw heads. The heads can be manipulated and
aligned using the Screw Holder with the Handle 03.607.006. (1)
Note: If Screw Holders have to be removed and re-inserted dur-
ing surgery, the Positioner for Screw Holder can be used. If the
rod is not inserted yet, apply the Positioner with the slender end
over the top of the 3-D head. If rod, sleeve and nut are already
inserted, apply the Positioner with the wider end over the 3-D
head (2).
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2
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Optional: Align rod and screw head with
Rod Introduction Pliers
Required instruments
Support for Rod Introduction Pliers 388.615
USS II Polyaxial Rod Introduction Pliers 03.607.009
USS Sleeve Pusher 388.502
Spreader Forceps for USS and Click’X, length 330 mm 388.410
If necessary, use the Rod Introduction Pliers to align the rod with
a screw head. Never use the Rod Introduction Pliers without
guidance provided by the Screw Holder.
Following alignment, use the Sleeve Pusher to insert sleeves.
Once the sleeve has been inserted with the Sleeve Pusher, the
nut can be inserted with the Socket Wrench 388.584 prior to
final tightening (step 7).
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6
Insert sleeves and nuts
Required instruments
Socket Wrench, bihexagonal, ⭋11.0 mm, self-holding,
with straight handle 03.607.008
USS II Polyaxial Handle 03.607.006
USS II Polyaxial Screw Holder 03.607.005
Use the self-holding Socket Wrench to pick up a sleeve and nut
from the loading station. Slide them over the Screw Holder onto
the screw head, and tighten the nut slightly. Although the rods
are now secured in the side-opening of the screw, the 3-D heads
still remain mobile.
Note: For constructions with more than two screws on each
side, start with the screw heads in the center.
7
Tighten the nuts
Required instruments
Socket Wrench for 12-point nut, with L-Handle 388.584
Socket Wrench ⭋5.0 mm, with T-Handle 388.143
USS II Polyaxial Screw Holder 03.607.005
Use the Socket Wrench with L-Handle to finally tighten the
nuts. Counteract torque using the Socket Wrench with T-Handle
placed over the Screw Holder.
Note: It is necessary to apply a tightening torque of 12 Nm to
secure the polyaxial screw heads tightly.
Remove the Screw Holders when all the screws are finally
tightened.
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Remobilization and/or removal
Required instruments
Socket Wrench, bihexagonal, ⭋11.0 mm, self-holding,
with straight handle 03.607.008
USS II Polyaxial Remobilizing Instrument 03.607.012
Stop Sleeve for Remobilizing without Rod 03.607.013
Hollow Reamer ⭋12.6 mm for USS II Polyaxial 03.607.014
USS II Polyaxial Screw holder 03.607.005
Note: Always apply the Screw Holder as a guide.
In the following situations, the USS II Polyaxial heads can be
remobilized with the Remobilizing Instrument:
1. Head with rod introduced
Loosen the nut with the Socket Wrench as far as possible.
Then slide the Remobilizing Instrument over the screw
head (make sure the red mark on the shaft with the T-Handle
is visible), and push the outer sleeve down. Turn the T-Handle
until it stops. The head is now mobile again.
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2. Head without rod
Apply the Stop Sleeve over the polyaxial head. Then apply the
Remobilizing Instrument as described before.
Note: If the head has to be removed, remove nut and sleeve
using the Socket Wrench. Remove the rods. Apply the Remobi-
lizing Instrument as described above without inserting the Stop
Sleeve. This is how the locking ring will be completely removed.
Then remove the polyaxial head with the Screw Holder.
Note: If the use of the Remobilizing instrument is hindered by
bone touching the polyaxial screw head, use the Hollow Reamer,
guided by the Screw Holder, to remove excessive bone first.
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