sur gical technique v2 · the 4.5 mm passmed pedicle screws should be used in the thoracic spine...

V2S U R G I C A L T E C H N I Q U E

P O L Y A X I A L S P I N E S Y S T E M

TRULY POLYAXIAL, SOLID AND POWERFUL

A DEcADE OF RESULTS


All the implants offerthe Polyaxiality, includingHooks, Claws, SacralPlates and of coursePedicle screws.

Exclusive Polyaxial Clawsystem for thoracicanchorage, excellentbone thread for pediclescrews, left and rightanatomical sacral plates using screws crossed in the 3 dimensions.

Ease of rod connectiondue to the Polyaxialityand Stability of allimplants, friendly userinstrumentation.

POLYAXIALITY STABILITY EFFICIENCY

TRULY POLYAXIAL, SOLID AND POWERFUL

INSTRUMENTATION

A01130010 3,5 mm Hexagonal Screwdriver shaft

A02110050 Depth gauge

A01110020 Squared awl reamer shaftA01110030 Straight threaded awl shaft A01110040 Squared awl shaft

A02120000 Rod holder

A02120250 Compressor

A01110110 Pedicle screwdriver shaft

A02120100 French benderA02100005 Palm ratchet handle for shafts

A01120020 Rod pusher shaftA01110050 Straight spatulaA01110060 Curved spatulaA01110070 Bone probe

A01160010 8mm Hex hollow nutdriver shaft

A01170601 Right in situ bender A01170602 Left in situ bender

A01130250 T20 Screwdriver

A01114500 Tap for ø 4.5 mm pedicle screwA01115500 Tap for ø 5.5 mm pedicle screwA01116500 Tap for ø 6.5 mm pedicle screwA01117200 Tap for ø 7.2 mm pedicle screw

A02120255 Set of jaws for compressor A02120250

A02100003 Malleable rod, length 150mm

A02100004 Malleable rod, length 350mm

A01130020 Selfholding nutdriver and breaker

A01130200 Nut driver shaft for final tightening

A02100001 Straight ratchet handle for shafts

A02100002 T ratchet handle for shafts

A02120350 Rod spreader A02120355 Set of jaws for spreader A02120350

A01120010 Rod rotating wrench 0° shaft

MS 503 Hook holder

MS 512 Hex. positionner wrenchfor claw

MS 507 Compressor forcepsfor claw

MS 502 Hook inserter set MS 505 Laminar and transverseprocess hook starter

MS 504 Pedicle hook starter

MS 510 Flexible nutdriver for claw

MS 515 Ratcheting wrenchfor claw nut

MS 214 Nutdriver and positionner for plate and rod

MS 511 Rod gripper

A01130300 Countertorque

MS 209 Templates set for rod plates

MS 524 Handle for sacral plate drill guide

MS 525 Drill guide for sacral plate

MS64102 Stylet with 2.5 mm Hexagon for Crosslink System

A01160010 8mm Hex hollow nutdriver shaft

MS 513 Double end wrench for claw nut

A02120375 Set of L-JAWS

MS 514 Flexible guiding tube

MS250 Complete empty trays displaying set for implants

A01100251 Case for PASS instruments

A01100500 PASS deformity case

MS 219 Pedicle probe MS 227 Connecting clamp releaser

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S U R G I C A L T E C H N I Q U EP O L Y A X I A L S P I N E S Y S T E M

PASSmed® (Polyaxial Spine System) is the result of collaboration between a group of spine surgeons and Medicrea™ since 1997. The Polyaxial Spine System facilitates spinal osteosynthesis for various deformities in the Thoraco-Lumbar or Lumbo-Sacral area. PASSmed® implants are made of Titanium (Ti-6A1-4v Eli), produce a solid construct and are user friendly.

SUMMARY

1. Lumbar Spine ................................................................................... 62. Thoracic Spine ................................................................................. 9

1. Thoracic fixation using a pediculo/transverse claw ............................... 112. Thoracic fixation using a pediculo/laminar claw ................................... 143. Lumbar fixation using a lamino/laminar claw ...................................... 16

1. Insertion of the S1 screw ................................................................. 182. Insertion of the bicortical inferior screw into the sacrum ala .................. 19

Rod-plate construct ............................................................................. 21

Rod Construct .................................................................................... 24

Reduction of the deformity ................................................................... 31

INSERTION Of vERTEbRAL ANCHORS 1ScRew FixAtion

INSERTION Of vERTEbRAL ANCHORS 2clAw FixAtion

3FixAtion USing A SAcRAl plAte

4Rod-plAte conStRUct

5Rod conStRUct

6‘‘ Rod to Rod ’’ linkAge

7RedUction oF the deFoRMitY

1. Transverse link ............................................................................... 30 2. Crosslink system ............................................................................ 30

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Ø (mm): 4,5 5,5 6,5 7,2 8

P O L Y A X I A L S P I N E S Y S T E MP O L Y A X I A L S P I N E S Y S T E M

Facetectomy: resection of the inferior articular process of the overlying vertebra using a gouge chisel.

Preparation of the implantation site:Decortication of the superior articular processof the instrumented vertebra using a rongeur.

The PASSmed polyaxial screws are available in different diameters and lengths. Each diameter is color-coded: Purple for 4.5 mm Dia., green for 5.5 mm Dia., blue for 6.5 mm Dia., gold for 7.2 mm Dia. and grey for larger Dia. screws.

The 4.5 mm PASSmed pedicle screws should be used in the thoracic spine ONLY. PASSmed 5.5 mm screws should be reserved for the upper lumbar spine (L1, L2 and L3). PASSmed 6.5 mm screws should be reserved for the lower lumbar spine (L4 and L5).Similarly, PASSmed 7.2 mm screws (or larger diameter screws) should be reserved forthe sacral spine or for revision surgery.

The height of the screw seating can be adjusted using Polyaxial Offset screws with a 3 mmor 6 mm offset. This will provide optimal alignment of the screw heads in the sagittal planeand/or compensation for bone loss (if any).

1. LUMBAR SPINE


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P O L Y A X I A L S P I N E S Y S T E M S U R G I C A L T E C H N I Q U EP O L Y A X I A L S P I N E S Y S T E M

Preparation of the pathway using the Curved spatula (A01110060) (or the Bone probe A01110070), with the concave surface of the instrument facing the spinal canal.

NOTE: The Straight threaded awl (A01110030) can also be used to prepare the pedicule pathway.

Location of the pedicle entry point and creation of a pilot hole with the Squared awl (A01110040): this hole is usually located at the intersection of a horizontal line which bisects the transverse process and a vertical line through the middle of the superior articular process.

IMPORTANT:For the superior end of the instrumentation, be sure to secure the screw position outside of the facet joint.

Test the pathway with the Pedicle probe (MS219). This pedicle feeler is used to check that the pedicle wall has not been breached.

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Enlargement of the hole with a curette and retesting with the Pedicle probe (MS219).

Preparation of the screw seating: in some cases a Pedicle reamer (A01110020) will be used for levelling the area that will accommodate the screw head. This is accomplished by hand, using a rotary motion.

NOTE: For a rod-plate construct used only in Lumbar area, a set of templates (MS 209) is available to help determine the appropriate rod-plate size. Insert two pins into the prepared pedicles; a template is selected such that it goes over these two pins. This corresponds to the appropriate rod-plate size.

NOTE : In case of hard bone, it can be useful to use one of the taps (A01114500, A01115500, A01116500 or A01117200 according to the screw diameter to be implanted), to prepare the pedicle screw insertion.

Taps diameters are undersized by 0.5mm.


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Insertion of the screw with the Pedicle screwdriver (A01110110).

Facetectomy: resection of the inferior articular process of the overlying vertebra using a gouge chisel.

2. THORACIC SPINE

Preparation of the implantation site: Decortication of both the transverse process and the base of the articular process of the instrumented vertebra using a rongeur.

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Preparation of the pathway using the Curved spatula (A01110060) (or the Bone probe A01110070), with the concave surface of the instrument facing the spinal canal (see figure p.7).

NOTE: The Straight threaded awl (A01110030) can also be used to prepare the pedicule pathway.

Test the pathway with the pedicle probe (MS219). This pedicle feeler is used to check that the pedicle wall has not been breached (see figure p.8).

Enlargement of the hole with a curette and retesting with the pedicle probe (MS219) (see figure p.8).

NOTE: In case of hard bone, WHILE TAKING PRECAUTION, it can be useful to use one of the taps to prepare the pedicle screw insertion (see figure p. 8). Taps diameters are undersized by 0.5mm. Insertion of the screw with the pedicle screwdriver (A01110110) (see figure p.9).

IMPORTANT: The use of an image intensifier (C-arm) is highly recommended for per-operative control of pedicle screw placement. Alternatively, a surgical navigation system can be used.

Location of the pedicle entry point and creation of a pilot hole using the awl (A01110040): this hole is usually located at the intersection of a horizontal line which runs through the upper third of the transverse process and a vertical line through the middle of the articular process.


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Preparation for placement of the pedicle hook using the Pedicle hook starter (MS 504).

The claw consists of two hooks facing each other, one main polyaxial hook and one counterhook which closes the claw.

There are several types of claws according to the levels instrumented, lumbar or thoracic. There is 2 types of thoracic claws: pediculo/transverse or pediculo/laminar.There is only 1 type of lumbar claw: lamino/laminar lumbar claw.

IMPORTANT:In countries where the use of pedicle screws is restricted at thoracic levels (e.g. USA), vertebral claws are only recommended.

Preparation for insertion of the threaded connecting rod: partial resection of the base of the transverse process of the underlying vertebra using a rongeur. This step is important as it facilitates both placement of the threaded connecting rod and nut, as well as handling of instruments.

1. THORACIC FIXATION USING A PEDICULO/TRANSVERSE CLAW:Combination of a polyaxial pedicle hook for claw available in 2 sizes: 4 mm (MS 421-0 ) or 6 mm (MS 421-1)and a transverse counterhook: MS 420-2S (with a short connecting rod) or MS 420-2L (with a long connecting

rod).


Preparation for placement of the transverse hook using the laminar and transverse process hook starter (MS 505) at the superior part of the transverse process.

NOTE: The resection of the inferior articular process of the above vertebra is also useful except if the joint has to be respected (claw of the upper extremity of the construct).

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1


Placement of the pedicle hook using the Hook inserter set (MS 502).


Placement of the transverse counter hook using the hook holder (MS503) and the hexagonal positioner wrench for claw (MS512).

Positioning of the pedicle hook using the Hook inserter set (MS502)

option : 2nd inSeRtion techniqUe

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2 3


Positioning of the transverse counterhook using the Hook holder (MS 503). Slightly tilt the pedicle hook adapted to the Hook inserter in order to facilitate the introduction.

Initial closing of the claw using the Compressor forceps for claw (MS 507).

Tightening of the locking nut on the threaded connecting rod using the Flexible nutdriver for claw (MS 510).

NOTE: The claw locking nut should be tight enough to allow the use of the Ratcheting wrench (MS 515).

Orientation and placement of the transverse counterhook using the Hexagonal hook positionner wrench (MS 512).

IMPORTANT: to facilitate the placement of the transverse counterhook, using a COBB can be helpful.

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Preparation of the site for the supra-laminar counterhook using a Kerisson punch. The creation of a large window is recommended to ease the insertion of the counterhook by simple rotation, without tilting.

NOTE: The resection of the inferior articular process of the above vertebra is also useful except if the joint has to be respected (claw of the upper extremity of the construct).

Preparation for insertion of the threaded connecting rod: partial resection of the transverse process basis of the underlying vertebra using a rongeur. This step is important as it facilitates both placement of the threaded connecting rod and locking nut, and handling of instruments (see figure p.11).

Preparation of the pedicle hook placement using the Pedicle hook starter (MS 504) (see figure p.11).

Placement of the pedicle hook using the Hook inserter set (MS 502) (see figure p.12).

Final tightening with the Ratcheting wrench (MS 515). This Ratcheting wrench provides a powerful tightening, therefore, be careful not to overtighten the nut and stop as soon as resistance is felt. Tightening direction is marked on the instrument.

NOTE: A double end wrench for claw nut (MS 513) is also available.

2. THORACIC FIXATION USING A PEDICULO/LAMINAR CLAW: Combination of a polyaxial pedicle hook for claw, available in 2 sizes: 4 mm (MS 421-0 ) or 6 mm (MS 421-1)and a supra-laminar counterhook:

MS 421-2S (with a short connecting rod) or MS 421-2L (with a long connecting rod).


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Orientation and placement of the supra-laminar counterhook using the Hexagonal positionner wrench (MS 512).

IMPORTANT: The use of a COBB can ease the placement of the supra-laminar counterhook.

Initial closing of the claw using the Compressor forceps for claw (MS 507) (see figure p.13).

Tightening of the claw locking nut on the threaded connecting rod using the Flexible nutdriver for claw(MS 510) (see figure p.13).


Final tightening with the Ratcheting wrench (MS 515), which provides powerful tightening. Therefore, be careful not to overtighten the nut and stop as soon as resistance is felt. Tightening direction is marked on the instrument (see figure p.14).

NOTE: A double end wrench for claw nut (MS 513) is also available.

Positioning of the supra-laminar counterhook using the Hook holder (MS 503). Slightly tilt the pedicle hook adapted to the Hook inserter in order to facilitate the introduction.

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Preparation of the site for the supra-laminar counterhook using a Kerisson punch. The creation of a large window is recommended to ease the insertion of the counterhook by simple rotation, without tilting.

3. LUMBAR FIXATION USING A LAMINO/LAMINAR CLAW:The lumbar claw consists of a combination between a polyaxial laminar hook for claw, available in 3 sizes: 7 mm (MS 430 -0 ), 9.3 mm (MS 430 -1) or 11 mm (MS 430 -3 )and a supra-laminar counterhook:MS 430 -2S (with a short connecting rod) or MS 430 -2L (with a long connecting rod).

NOTE: Alternatively, the lumbar claw can be placed with the polyaxial laminar hook in the supra-laminar position and the counterhook in the infra-laminar position.

Preparation for placement of the polyaxial infra-laminar hook using the Laminar and transverse process hook starter (MS 505).


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Placement of the polyaxial infra-laminar hook using the Hook inserter set (MS 502).

Positioning of the supra-laminar counterhook using the hook holder (MS 503) (see figure p.15).

Orientation and placement of the supralamina counterhook using the Hexagonal positionner wrench (MS 512)(see figure p.15).

IMPORTANT: To ease the placement of the counterhook, using a COBB gouge can be helpful.

Initial closing of the claw using the Compressor forceps for claw (MS 507) (see figure p.13).

Tightening of the claw locking nut on the threaded connecting rod using the Flexible nutdriver for claw (MS 510) (see figure p.13).


Final tightening with the Ratcheting wrench (MS 515), which provides powerful tightening. Therefore, be careful not to overtighten the nut and stop as soon as resistance is felt. Tightening direction is marked on the instrument (see figure p.15).

NOTE: a double end wrench for claw nut (MS 513) is also available.

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Creation of a starter hole following the good direction and according to the surgeon preference (use of a Straight spatula A01110050, creation of the pathway through the anterior cortex for a bicortical fixation of the S1 screw.

Test the pathway with the Pedicle probe (MS219). This pedicle feeler is used to check that the anterior cortex has been passed.

Enlargement of the hole with a curette.

Determination of the appropriate screw length using the depth gauge (A02110050).

Facetectomy: resection of the inferior articular process of L5 using a gouge chisel.

Identification of the S1 pedicle entry point which is in the inferior part of the S1 articular surface.

1. INSERTION OF THE BICORTICAL S1 SCREW:

Placement of the sacral plate and insertion of the S1 screw with the 3.5 mm Hexagonal screwdriver (A01130010).

NOTE: in order to check the correct position, we recommand to use a lateral view from the image intensifier (C-arm).


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2. INSERTION OF THE BICORTICAL INFERIOR SCREW INTO THE SACRUM ALA:

Determination of the entry point: the drill guide for sacral plate (MS 525) is inserted through the inferior hole of the sacral plate. The entry point is located lateral to the first sacral hole. It is also possible to adapt the handle for sacral plate drill guide (MS 524) to hold the guide. The straight threaded awl (A01110030) is inserted through the drill guide and gives the correct lateral and cephalad direction for the inferior screw.

Creation of the inferior screw pathway through the anterior cortex for a bicortical fixation using the straight spatula (A01110050).

Test the pathway with the pedicle probe (MS219). This pedicle feeler is used to check that the anterior cortex has been passed.

Determination of the appropriate screw length using the depth gauge (A02110050).

Positioning of the plate. Its lower end is lying on the sacral ala, lateral to the first posterior sacral foramen.

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Insertion of the screw with the 3.5 mm Hexagonal screwdriver (A01130010).

Sacral plates are coming with a polyaxial extension and in anatomical configuration (Left: MS 031, Right: MS030).


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IMPORTANT NOTE:When using a “Screw to Screw” Crosslink, the appropriate Crosslink length should be determined BEFORE loading the rod-plates over the flexible guiding tubes. With guiding tubes in place over two threaded extensions at the same level, load the Crosslink (marking facing upward) over the two guiding tubes. Should the Crosslink not slide all the way down on both sides, try an alternate length Crosslink. The final loading of the appropriate “Screw to Screw” Crosslink is described after (please refer to page 22).

Rod-plates are offered in two versions (with 2 or 3 holes) for one or two-level instrumentation, each being available in two sizes, small and large (for pro-per sizing, please refer to above section, page 8).

The rod-plates are positioned with the flexible guiding tubes in place over the threaded extensions of the anchorage points.Rod-plates are delivered pre-bent to match the lumbar or lumbo-sacral lordosis. The implantation of the rod-plates is restricted ONLY in this area.

NOTE: Further bending of the rod-plate is not recommended, as this may cause distortion of the rod-plate holes.

Using Flexible guiding tubes (MS 514) over the threaded extensions of each polyaxial implants will facilitate the positioning of the rod-plates at distance of the spine.


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In order to achieve a proper connection, make sure that the osteophytes have been removed (if any), with a rongeur.

The circular hole in the rod-plate should always be positioned at the proximal end of the construct, away from the facet joints.

Should the rod-plate holes not be aligned with the pedicle implants, a rod construct should be used.

After the rod-plates have been loaded, the selected “Screw to Screw” Crosslink is connected over the flexible guiding tubes (marking facing upward).

The locking nuts are loaded in the Nutdriver and and breaker instrument (A01130020) and partially tightened on top of the threaded extensions.

NOTE:• The locking nuts for pedicle screws are symetrical.

• A flat nut (MS001) has to be used with the sacral plates, all the polyaxial hooks or a “screw to screw” crosslink.

This flat nut is delivered pre-charged with the hooks or sacral plates and separately for the “Screw to Screw” crosslink.

LOCKING OF THE THREADED EXTENSION AND NUT TIGHTENINGThe nut tightening is achieved after a specific threaded post orientation and locking, using the Nutdriver and Positionner for Plate and Rod (MS 214).

This instrument consists of two sliding parts:1. The nutdriver is the outer part.2. The alignment guide is the inner part. Its distal end is designed to fit the semicircular section at the superior extremity of the threaded extension in order to control the rotation. The 2 flats of the threaded extension basis have to be properly oriented to fit in the rod-plate. This blocks the rotation of the threaded extension during the nut tightening.The long T-handle of the alignment guide (inner part of MS 214) has to be perpendicular to the rod-plate axis. The drawing of the rod-plate (on this long T-handle) will face the surgeon (or his assistant, in front of him). This position of the long T-handle should be maintained during nut tightening.This step is critical to ensure proper locking of the rod-plate on the implants.

To make sure that optimal tightening has been achieved, check that: •thesemicircularsectionattheendofthethreadedextensionisparallel to the rod-plate axis, AND •thegrooveonthethreadedextensionisflushwiththetopsurfaceofthenut.

Should this not be the case, loosen the nut and change the orientation of the threaded extension so that the flats of its basis are properly captured within the rod-plate.


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Thread the nutdriver and breaker instrument (A01130020) on top of the threaded extension and snap off along the longitudinal axis of the rod-plate.

At the end, after the threaded extension has been snapped off, check finally that its semicircular section is parallel to the rod-plate axis, and is flush with the top surface of the nut.

FINAL PROCEDUREFinal tightening of each locking nut is realized with the nutdriver shaft for final tightening (A01130200). The position of this dynamometric nutdriver must go until the stop providing an optimal torque ranging between 12 and 13 Nm (8.85 and 9.59 lbf.ft).

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IMPORTANT NOTE:When using a “Screw to Screw” Crosslink, the appropriate Crosslink length should be determined BEFORE loading the connecting clamps over the flexible guiding tubes. With guiding tubes in place over two threaded extensions at the same level, load the Crosslink (marking facing upward) over the two guiding tubes. Should the Crosslink not slide all the way down on both sides, try an alternate length Crosslink. The final loading of the appropriate “Screw to Screw” Crosslink is described after (please refer to page 30).

BENDING OF THE RODS

The rod is held with the Rod holder (A02120000) and contoured using the French rod bender (A02120100). The rod should be bent to the ideal sagittal curve, according to the instrumented levels and length of the construct. A longitudinal line can assist the rod contouring.

A selection of the appropriate rod length and determination of the ideal shape can be facilitated by using the malleable rod (A02100003 or A02100004).

NOTE : For short rods (from 40 to 110 mm) our PASSmed system provides pre-bent rods to facilitate the rod contouring by the surgeon.

IMPORTANT: for traceability reasons we do not recommend the cutting of our rods.

Using Flexible guiding tubes (MS 514) over the threaded extensions of each polyaxial implants will facilitate positioning of the connecting clamps and rods at distance of the spine.

5Rod conStRUct

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(b)

(a)


ADAPTATION OF THE RODSConnecting clamps are adapted on the first rod.Then, this assembly is dropped over the Flexible guiding tubes and brought down to the implants, usually with the rods placed medially to the implants.

A rod construct requires the use of connecting clamps.

LOADING OF THE CONNECTING CLAMPSThe upper and lower parts of the connecting clamps have distinct geometries:The top of the chosen clamp which is identified by laser marking (letter “T” or “S”) will receive the locking nut.The lower part of the clamp fits the hemispherical part of the implant head (polyaxial Screw, Hook or Sacral plate).

There are two types of connecting clamps:

(a) Special connecting clamp (MS 012) which is marked “S” (for superior).This connecting clamp has been specially designed to slide easier along a bent rod due to a beveled edge.

(b) Realignment connecting clamp (MS 121) which has a golden color and is thicker in its lower part than the standard connecting clamp. The top of the clamp is identified by the letter “T” and the word “RAPPEL”.This clamp is only used if the surgeon needs a realignment effect between the pedicular part of a pedicle screw and its posterior threaded extension. At the end of tightening, the hemispherical part of the screw head will be completely countersunk in the lower part of the clamp, and the polyaxial screw will be perpendicular to the rod (like a standard monoaxial screw).

It can be useful when a vertebral realignement is necessary, ie.: spondylolisthesis or fracture. We do not recommend the use of a realignment connecting clamp in case of poor bone quality (i.e.: severe osteoporosis…).

(b)

NOTE:A Connecting clamp releaser (MS 227) can be used if necessary to open gently the connecting clamp and facilitatesits sliding along the rod in case ofsevere bending.

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In order to achieve a proper connection, make sure that the osteophytes have been removed (if any), with a rongeur.After the rod has been loaded with the appropriate connecting clamps, the selected “Screw to Screw” Crosslink is connected over the flexible guiding tubes (marking facing upward).

The locking nuts are loaded in the Nutdriver and and breaker instrument (A01130020) and partially tightened on top of the threaded extensions.

NOTE:•The locking nuts for pedicle screws are sym-metrical. • A flat nut has to be used with the sacral plates, all the polyaxial hooks or a “Screw to Screw” crosslink.This flat nut is delivered pre-charged with the hooks or sacral plates and separatly (MS001) for the “Screw to Screw” crosslink.

If necessary, use the Rod pusher (A01120020) to facilitate rod approximation.

The threaded extensions are completely free during this step and there is no stress on the anchorage.

5Rod conStRUct

27


When all the locking nuts are adapted to each threaded extensions, the rod is then positioned in the correct sagittal plane.A rod rotating wrench (A01120010) is available to assist in rotating the rod (when needed). Apply the wrenches to the flats, at the end of the rod.

LOCKING OF THE THREADED EXTENSION AND NUT TIGHTENINGThe nut tightening is achieved after a specific threaded post orientation and locking, using the Nutdriver and Positionner for Plate and Rod (MS 214) which blocks rotation and locks direction of the threaded extension during nut tightening.

This instrument consists of two sliding parts:1. The nutdriver is the outer part.2. The alignment guide is the inner part. Its distal end is designed to fit the semicircular section at the superior extremity of the threaded extension in order to control the rotation. The 2 flats of the threaded extension basis have to be properly oriented to fit into the rod. This blocks the rotation of the threaded extension during the nut tightening.The long T-handle of the alignment guide (inner part of MS 214) has to be parallel to the rod axis.The drawing of the rod (on this long T-handle) will face the surgeon (or his assistant, in front of him).This position of the long T-handle should be maintained during nut tightening.This step is critical to ensure proper locking of the rod-plate on the implants.

To make sure that optimal tightening has been achieved, check that: •thesemicircularsectionattheendofthethreadedextensionis perpendicular to the rod axis, AND •thegrooveonthethreadedextensionisflushwiththetopsurfaceofthenut.

Should this not be the case, loosen the nut and change the orientation of the threaded extension so that the flats of its basis are properly captured within the connecting clamp.

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DISTRACTION-COMPRESSIONBefore the final tightening and procedure, it may be necessary to use distraction or compression at the instrumented levels.

When using a rod construct, distraction should be applied with the Spreader (A02120350) associated with the standard jaws for spreader A02120355: Position the forks of the instrument on the rod, flush against the inner sides of the adjacent connecting clamps.

Compression can be achieved with the Compressor A02120250 associated with the standard jaws for compressor A02120255: As with the Spreader, position the forks of the instrument on the rod, flush against the outer sides of the adjacent connecting clamps.

FINAL PROCEDUREFinal tightening of each locking nut is realized with the nutdriver shaft for final tightening (A01130200). The position of this dynamometric nutdriver must go until the stop providing an optimal torque ranging between 12 and 13 Nm (8.85 and 9.59 lbf.ft).

The Countertorque (A01130300) is used to stabilize the rod during the final tightening of the nut.

5Rod conStRUct

OPTION : A L shaped jaws (A02120375) can be also used to apply both distraction or compression directly on the connecting clamps.

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Thread the Nutdriver and breaker instrument (A01130020) on top of the threaded extension and snap off along the longitudinal axis of the rod.

At the end, after the threaded extension has been snapped off, check finally that its semicircular section is perpendicular to the rod axis, and is flush with the top surface of the nut.

NOTE:The extension of the assembly is possible through the use of 2 types of dominos (Open/Closed Domino MS025 or Closed Domino MS026) and their Screwdriver (A01130250).

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1

2

3


2. CROSSLINK SYSTEM:The Crosslink System is composed of two connectors pre-connected on one connecting plate. This implant is available in 3 sizes (MS44162234, MS44163448 and MS44164862) covering the distances between rods from 22 mm to 62 mm.

Before positioning the connectors, please check that the rod passage is free. If not, release the passage by untightening the central axis using the MS64102 stylet until stop position (see figure 1).

Once the connector is on the rod, to prevent a rod escape during distraction and compression manoeuvres, it is necessary to tighten the central axis until stop using the MS64102 Stylet. The Crosslink can then slide freely along the rod without escape, and a gentle compression or distraction can be applied between the 2 rods (see figure 2).

Final Locking is achieved by tightening the locking nut using the Screwdriver A01160010 pre-assembled with the handle A02100001 (see figure 3).

The handle A02100002 should not be used to perform the final tightening.

6‘‘ Rod to Rod ’’ linkAge

1. TRANSVERSE LINK:A “Rod-to-Rod” transverse link can be adapted to the construct at the end of the surgery. 3 sizes are available (MS 452, MS 453 and MS 454). Freedom of the threaded rod within the two hooks allows easy placement of the Transverse link whatever the respective positions of the rods. The Transverse link stability and rigidity are achieved with compression through tightening of the lateral lock nut. The initial threading of the lock nut is performed with the Double end wrench for claw nut (MS 513) until the lock nut is tight enough to allow the use of the Ratcheting wrench (MS 515) which tights and provides the compression.

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To turn the rods the surgeon will use 2 Rod grippers (MS511). The 2 rods can be rotated separately or simultaneously.

Using Flexible guiding (MS 514) over the threaded extensions of each polyaxial implants will facilitate positioning of the connecting clamps and rods at distance of the spine.The connecting clamps are adapted on the first rod (generally the convex rod of the deformity).

IMPORTANT:When a rod is properly oriented, it must be locked on an implant (a claw or a screw) at the upper end of the construct.


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NOTE: PASSmed instrumentation allows also the reduction of deformities using a rotation manoeuvre. This rotation manoeuvre can be associated at any time with a translation manœuvre.

Progressive reduction of a deformity is achieved through an alternative tightening of all the nuts on both rods. With gentle tightening, the reduction forces are distributed over all the vertebrae toward the rods, as illustrated on the following pictures.

IN SITU BENDINGIn order to perform in situ bending, a Ø6 mm rod (length 500 mm) made of Pure Titanium T40 (B01176500) was specially integrated to the PASSmed System. To avoid any confusion with the standard rods, this rod is colored in blue.

The in situ bending will be achieved by using the Right in situ Bender (A01170601) and the left in situ Bender (A01170602).


IMPLANTS

REF. DESIGNATION*

MS 348C SACRAL SCREW D. 6.5mm L. 60mm

MS 359C SACRAL SCREW D. 7,2mm L.30mm

MS 349C SACRAL SCREW D. 7,2mm L. 34mm







MS 108 ROD-PLATE 1 LEVEL SMALL

MS 109 ROD-PLATE 1 LEVEL LARGE

MS 110 ROD-PLATE 2 LEVELS SMALL

MS 111 ROD-PLATE 2 LEVELS LARGE

MS 012 SPECIAL CONNECTING CLAMP for DEFORMITY

MS 121 SPECIAL REALIGNMENT CLAMP

MS 129 ROD D. 6mm L. 40mm































B01176004 PRE BENT ROD 6mm L. 40mm








MS 001 NUT for CROSSLINK

MS 148 CROSSLINK L = 30mm









MS 452 SMALL TRANSVERSE LINK

MS 453 MEDIUM TRANSVERSE LINK

MS 454 LARGE TRANSVERSE LINK

B01176500 Ø6 x 500mm ROD for IN SITU BENDING

MS025 OPEN/CLOSED DOMINO for Ø6mm ROD

MS026 CLOSED DOMINO for Ø6mm ROD

MS44162234 CROSSLINK SYSTEM for Ø6mm ROD, DISTANCES 22 to 34mm



B01130001 LOCKING NUT

REF. DESIGNATION*

MS 183C POLYAxIAL CYL. PEDICULAR SCREW D.4,5mm L.25mm with nut































MS 838C POLYAxIAL CYL. PEDICULAR SCREW D.8mm L.38mm with nut





MS 304C POLYAxIAL CYL. PEDICULAR OFFSET 3mm SCREW D.5,5mm L.38mm with nut








MS400 4mm POLYAxIAL PEDICLE HOOK

MS401 6mm POLYAxIAL PEDICLE HOOK

MS410 6mm POLYAxIAL LUMBAR LAMINAR HOOK



MS421-0 4mm POLYAxIAL PEDICLE HOOK for CLAW

MS421-1 6mm POLYAxIAL PEDICLE HOOK for CLAW

MS430-0 7mm POLYAxIAL LUMBAR LAMINAR HOOK for CLAW

MS430-1 9,3mm POLYAxIAL LUMBAR LAMINAR HOOK for CLAW

MS430-3 11mm POLYAxIAL LUMBAR LAMINAR HOOK for CLAW

MS421-2S 7mm LAMINAR THORACIC HOOK for SHORT CLAW

MS420-2S 8mm LAMINAR LUMBAR or TRANSVERSE HOOK for SHORT CLAW

MS430-2S 9,3mm LAMINAR LUMBAR HOOK for SHORT CLAW

MS421-2L 7mm LAMINAR THORACIC HOOK for LARGE CLAW

MS420-2L 8mm LAMINAR LUMBAR or TRANSVERSE HOOK for LARGE CLAW

MS430-2L 9,3mm LAMINAR LUMBAR HOOK for LARGE CLAW

MS 031 LEFT SACRAL PLATE

MS 030 RIGHT SACRAL PLATE







* Not all items listed have been FDA approved and may not be available within the US market. Please check with Medicrea USA Customer Service for more information (201-222-3063).

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Pre-op Post-op

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Rod construct

Rod plate construct

Distributed by:

Manufacturer:

MEDICREA TechnologiesZ.I. Chef de Baie17000 LA ROCHELLE - FRANCETel. +33 (0)5 46 00 55 55 Fax +33 (0)5 46 00 55 77

RCS La Rochelle 380 133 918 SAS au capital de 696 960 Euros

www.medicrea.com

Headquarters:

MEDICREA24 porte du Grand Lyon01700 NEYRON - FRANCETél. +33 (0)4 72 01 87 87Fax +33 (0)4 72 01 87 88

[email protected]

sur gical technique v2 · the 4.5 mm passmed pedicle screws should be used in the thoracic spine...

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