Technique Guide - University of Iceland · The Synthes Occipito-Cervical Fusion System in combination with a Synthes posterior screw-rod system (e.g. Axon) is intended to provide

Occipito-Cervical Fusion System.Implants and instruments designed tooptimize fixation to the occiput.

Technique Guide

0x6.000.755_printversion.qxp 15.02.2007 8:36 Uhr Seite Cvr1


Synthes 1

WarningThis description alone does not provide sufficient back-ground for direct use of the instrument set. Instruction by asurgeon experienced in handling these instruments is highlyrecommended.

Cleaning of instrumentsFor detailed information please refer to “Reprocessing,Care and Maintenance of Synthes Instruments”, ArticleNo. 035.000.090.

Table of Contents

Image intensifier control

Introduction

Product Information

Surgical Technique

Overview 2

AO ASIF Principles 4

Indications and Contraindications 5

Implants 6

Instruments 10

Set 14

Patient Positioning 15

Occipito-Cervical Fixation with Occipital Plate 16

Occipito-Cervical Fixation with Occipital Clamps 26

Occipito-Cervical Fixation with Occiput Rods 34

0x6.000.755_printversion.qxp 15.02.2007 8:36 Uhr Seite 1

The Synthes Occipito-Cervical Fusion System is intended toprovide stabilization and promote fusion of the occipito-cer-vical junction. The Occipito-Cervical Fusion System includes acomplete set of implants and instruments designed to opti-mize fixation to the occiput and easily connect with all Syn-thes posterior cervical and thoracic rod-screw systems.

Overview

2 Synthes Occipito-Cervical Fusion System Technique Guide

Occipital plate, medial Occipital plate, lateral

Occipito-Cervical Fusion System with Axon

Versatile fixation possibilities to the Occiput

The Occipito-Cervical Fusion System offers several implantoptions to maximize fixation to the occiput and minimize theimplant footprint.


Synthes 3

Occipital clamps, 1 hole

Occiput rods

Occipital clamps, 2 holes


AO ASIF Principles

In 1958, the Association for the Study of Internal Fixation(AO ASIF) formulated four basic principles1, which havebecome the guidelines for internal fixation. They are:

– Anatomical reduction– Stable internal fixation– Preservation of blood supply– Early, active pain-free mobilization

The fundamental aims of fracture treatment in the limbsand fusion of the spine are the same. A specific goal in thespine is returning as much function as possible to theinjured neural elements.

AO ASIF Principles as applied to the spine2

Anatomical reductionRestoration of normal spinal alignment to improve thebiomechanics of the spine.

Stable internal fixationStabilization of the spinal segment to promote bony fusion.

Preservation of blood supplyCreation of an optimal environment for fusion.

Early, active pain-free mobilizationMinimization of damage to the spinal vasculature, dura, andneural elements, which may contribute to pain reduction andimproved function for the patient.

1 Müller ME, Allgöwer M, Schneider R, Willenegger H (1995) Manual of InternalFixation. 3rd, exp. a. completely rev. ed. 1991. Corr. 3rd printing. Berlin,Heidelberg, New York: Springer

2 Aebi M, Thalgott JS, Webb JK (1998) AO ASIF Principles in Spine Surgery. Berlin,Heidelberg, New York: Springer



Indications and Contraindications

The Synthes Occipito-Cervical Fusion System in combinationwith a Synthes posterior screw-rod system (e.g. Axon) isintended to provide stabilization to promote fusion of thecervical spine and occipito-cervical junction (Occiput-Th3) forthe following indications:

IndicationsOccipito-cervical and upper cervical spine instabilities:– Rheumatoid arthritis– Congenital anomalies– Posttraumatic conditions– Tumors– Infections

Instabilities in the lower cervical and upper thoracic spine:– Posttraumatic conditions– Tumors– Iatrogenic instabilities following laminectomy etc.

Degenerative and painful posttraumatic conditions in thelower cervical and upper thoracic spine.

Anterior cervical fusions requiring additional posteriorstabilization.

Contraindication– Spinal destruction accompanied by a loss of ventral sup-

port (caused by tumors, fractures and infections) results inmajor instability of the cervical spine and upper thoracicspine. In this situation, stabilization with this system aloneis not sufficient. Additional anterior stabilization is crucial.

– Severe osteoporosis

Synthes 5


Implants


Occipital plates

– Pure titanium (TiCP)– Allow 15° of screw angulation– Plates adapt to medial / lateral rod placement

Art. No. Type Width

04.161.001 Medial 50 mm

04.161.002 Medial 60 mm

04.161.011 Lateral 50 mm

04.161.012 Lateral 60 mm

Occipital clamps

– Pure titanium (TiCP)– One and two screw hole configuration– Allow 15° of screw angulation– Clamp facilitates easy connection to rod– Small footprint / low profile

Art. No. Type

04.161.023 1 hole

04.161.024 2 holes

Medial, 50 mm width Medial, 60 mm width

Lateral, 50 mm width Lateral, 60 mm width


Synthes 7

Occiput rod � 3.5 mm

– Pure titanium (TiCP)

Art. No. Overall length

04.161.030 230 mm

Rod � 3.5mm

– Titanium alloy (TAN)– Stress relieved to maintain strength

Art. No. Type Overall length

04.161.032 Pre-bent 250 mm


Implants

Occipital screws � 4.5 mm

– Titanium alloy (TAN)– Drill � 3.2 mm– Tap � 4.5 mm– Lengths 4 mm to 18 mm in 2 mm increments– Self-retaining Stardrive T15 interface– Blunt tip

Art. No. Bone purchase

04.601.104 4 mm

04.601.106 6 mm

04.601.108 8 mm

04.601.110 10 mm

04.601.112 12 mm

04.601.114 14 mm

04.601.116 16 mm

04.601.118 18 mm


Occipital screws � 5.0 mm

– Titanium alloy (TAN)– Rescue screw for screws � 4.5 mm– Lengths 4 mm to 18 mm in 2 mm increments– Self-retaining Stardrive T15 interface– Blunt tip

Art. No. Bone purchase

04.601.204 4 mm

04.601.206 6 mm

04.601.208 8 mm

04.601.210 10 mm

04.601.212 12 mm

04.601.214 14 mm

04.601.216 16 mm

04.601.218 18 mm


Synthes 9

Locking screw

– Titanium alloy (TAN)– Self-retaining Stardrive T15 interface

Art. No.

406.104


03.161.001 Bending Template for Occipital Plate,medial, small

03.161.002 Bending Template for Occipital Plate,medial, large

03.161.011 Bending Template for Occipital Plate,lateral, small

03.161.012 Bending Template for Occipital Plate,lateral, large

388.868 Trial Rod � 3.5 mm

03.161.003 Occiput Trial Rod � 3.5 mm

Instruments



Synthes 11

387.689 Plate Holder

391.880 Vice Grip

03.161.042 Bending Pliers for Occipital Plate

03.161.023 Drill and Tap Sleeve with Scale, forNos. 03.161.024 and 03.161.026

Drill and Tap depths can be adjusted from4 mm to 18 mm (in 2 mm increments).

324.107 Handle with Quick Coupling

For use with drill bit, taps and screwdrivers.


03.161.024 Drill Bit � 3.2 mm with Stop, 2-flute, for Quick Coupling

Instruments


03.161.026 Tap for Cortex Screw � 4.5 mm,for Quick Coupling

03.161.027 Tap for Cortex Screw � 4.5 mm, withCardan Joint, for Quick Coupling

03.161.028 Depth Gauge for Screws � 3.5 to 5.0 mm,measuring range to 50 mm

Provides direct measurement for screwselection.

388.392 Screwdriver Shaft Stardrive, T15, self-holding, for Quick Coupling

03.161.031 Screwdriver Shaft Stardrive T15, self-holding, with Cardan Joint, for QuickCoupling


Synthes 13

388.407 Holding Forceps for Rods � 3.5 mm

Provide a secure insertion of the rod intothe operative site.

03.161.041 Positioning Instrument for Occipital Plate


Occipito-Cervical Fusion System inVario Case (01.601.010)


68.601.010 Vario Case for Occipito-Cervical FusionSystem


Synthes 15

Patient Positioning

1Position the patient

Patient positioning is critical for occipito-cervical fusionprocedures.

Place the patient in the prone position with the patient’shead securely immobilized. Confirm proper patient positionby direct visualization and radiograph prior to draping.

Note: Always use caution when positioning the patient, asphysiological alignment may not be attainable.



Occipito-Cervical Fixation withOccipital Plate(Shown in combination with Axon; can also be usedwith CerviFix or StarLock)

1Fixation to the cervical and upper thoracic spine

Recommended set

187.098 Axon

Insert bone screws and/or hooks into the cervical and upperthoracic spine as required by the patient’s pathology.The technique is described in the Axon Technique Guide(036.000.179)

2Determine shape and size of occipital plate

Instruments

03.161.001/03.161.002 Bending Template for OccipitalPlate, medial, small/large

03.161.011/03.161.012 Bending Template for OccipitalPlate, lateral, small/large


Select a bending template of the plate style estimated tobest fit the occiput. Estimate the medial / lateral distance ofthe rods to determine the appropriate plate size. Contourthe plate template to fit the anatomy.


Synthes 17

3Contour occipital plate

Instruments

03.161.042 Bending Pliers for Occipital Plate

Use the bending pliers for contouring the plate to fit theanatomy. They can be used across any section of the plateincluding the area lateral of the rod attachment bodies.

Optional instruments

391.880 Vice Grips

To create more acute bends vice grips can be used.

Notes:– Reverse bending of the plates should not be attempted.– Extreme bending over the rod attachment body travel slot

will limit the amount of medial / lateral adjustment in therod attachment body.

– Extreme bending over the screw holes will limit the abilityto insert the screw properly.

This side must point upwards

Rod AttachmentBody

Rod Attachment BodyTravel Slot



4Drill pilot hole

Instruments

03.161.023 Drill and Tap Sleeve with Scale

03.161.024 Drill Bit � 3.2 mm with Stop, 2-flute,for Quick Coupling



Set the drill and tap sleeve to the desired depth. Slide backthe latch of the drill and tap sleeve to release its inner tube.Adjust position of inner tube in window so that the mark onthe inner tube indicates the required depth. Release the latchto lock the drill and tap sleeve at the desired depth.

Drill to desired trajectory and depth using the drill bit and thedrill and tap sleeve. Drilling must occur through the occipitalplate to ensure proper drilling depth.

Occipito-Cervical Fixation with Occipital Plate


Synthes 19

5Measure hole depth

Instruments

03.161.028 Depth Gauge

Use the depth gauge to confirm hole depth and selectthe corresponding screw length. The depth gauge must sitdirectly on the bone.

Note: The depth gauge measures the working length. Ifreading e.g. 10 mm on the depth gauge, select a 10 mmscrew.


1

2



6Tap

Instruments


03.161.026 Tap for Screws � 4.5 mm, for QuickCoupling


Tap to desired depth using the tap and the drill and tapsleeve. Tapping must occur through the occipital plate toensure proper tapping depth.

Note: Tapping is recommended for all screws


03.161.027 Tap for Screws � 4.5 mm, with CardanJoint, for Quick Coupling

388.407 Holding Forceps

Set the tap depth by turning the tap sleeve to the desireddepth (1). Lock the tap sleeve by turning down the lockingnut until it contacts the tap sleeve (2). Finger tighten thelocking nut. Use the holding forceps to provide axial forceand stability. Tapping must occur through the occipital plateto ensure proper tapping depth.



03.161.031 Screwdriver Shaft Stardrive T15,self-holding, with Cardan Joint,for Quick Coupling


Alternatively the screwdriver shaft with cardan joint may beused to insert the selected screw. Use the holding forceps toprovide axial force and stability.

7Insert screw

Instruments

388.392 Screwdriver Shaft Stardrive T15,self-holding, for Quick Coupling


Load the selected � 4.5 mm occipital screw from the screwrack. Insert screw and tighten it provisionally.

Note: A � 5.0 mm occipital screw may be used if the pri-mary screw has less than optimal fixation.

Synthes 21


8Insert remaining screws

Repeat steps 4 – 7 to insert the remaining screws.

Note: A minimum of three screws is recommended.


9Contour trial rod

Instruments

388.868 Trial Rod � 3.5 mm

Contour the trial rod to fit the anatomy and to seat fully inthe bone screws. Create the occipito-cervical bend and en-sure sufficient rod length to connect with the occipital plate.



11Rod Attachment

Instruments

388.407 Holding Forceps for Rods � 3.5 mm




Use the positioning instrument to facilitate rod placementand locking screw insertion.

Insert rod into the rod attachment body. Ensure that therod extends slightly past the end of the plate. Provisionallytighten the locking screw using the screwdriver shaftStardrive with the handle with quick coupling.

10Bend and cut rod

Instruments

389.478 Bending Pliers for Rods � 3.5 mm

391.990 Cutting Pliers for Plates and Rods

Contour the rod using the bending pliers to match the curveof the trial rod.

Cut the rod with the cutting pliers to the appropriate length.

Note: Repeated bending may weaken the rod.

Synthes 23



03.161.031 Screwdriver Shaft Stardrive T15,self-holding, with Cardan Joint, forQuick Coupling


Alternatively the screwdriver shaft with cardan joint may beused for provisional tightening of the locking screw. Use theholding forceps to provide axial force and stability.

12Insert rod in contralateral side

Repeat steps 9–11 to insert rod in contralateral side.





03.161.031 Screwdriver Shaft Stardrive T15,self-holding, with Cardan Joint, forQuick Coupling


Alternatively the screwdriver shaft with cardan joint may beused for final tightening of the occipital and locking screws.Use the holding forceps to provide axial force and stability. Toprovide counter-torque for tightening the locking screws, thepositioning instrument may be used.

13Final tightening

Instruments




Firmly tighten all occipital and locking screws using thescrewdriver shaft Stardrive with the handle with quick cou-pling. To provide counter-torque for tightening the lockingscrews, the positioning instrument may be used.

Synthes 25


Occipito-Cervical Fixation withOccipital Clamps(Shown in combination with Axon; can also be usedwith CerviFix or StarLock)


Recommended set

187.098 Axon

Insert bone screws and/or hooks into the cervical and upperthoracic spine as required by the patient’s pathology. Thetechnique is described in the Axon Technique Guide(036.000.179)

2Contour trial rod

Instruments

388.868 Trial Rod � 3.5 mm

Contour the trial rod to fit the anatomy and to seat fully inthe bone screws. Create the occipito-cervical bend andensure sufficient rod length to connect with the occipitalclamp.



3Bend and cut rod

Instruments



Contour the rod using the bending pliers to match the curveof the trial rod.



4Attach occipital clamp to rod

Instruments




Provisionally attach the occipital clamp to the rod by tighten-ing the set screw in the clamp.

Synthes 27


Occipito-Cervical Fixation with Occipital Clamps

5Drill pilot hole

Instruments






Drill to desired trajectory and depth using the drill bit anddrill and tap sleeve. Drilling must occur through the occipitalclamp to ensure proper drilling depth.



6Measure hole depth

Instruments


Use the depth gauge to confirm hole depth and selectthe corresponding screw length. The depth gauge must sitdirectly on the bone.

Note: The depth gauge measures the working length, ifreading e.g. 10 mm on the depth gauge, select a 10 mmscrew.

7Tap

Instruments




Tap to desired depth using the tap and the drill and tapsleeve. Tapping must occur through the occipital clamp toensure proper tapping depth.

Note: Tapping is recommended for all screws.

Synthes 29


1

2





Set the tap depth by turning the tap sleeve to the desireddepth (1). Lock tap sleeve by turning down the locking nutuntil it contacts the tap sleeve (2). Finger tighten the lockingnut. Use the holding forceps to provide axial force and sta-bility. Tapping must occur through the occipital clamp to en-sure proper tapping depth.



8Insert screw

Instruments




Note: A � 5.0 mm occipital screw may be used if theprimary screw has less than optimal fixation.


03.161.031 Screwdriver Shaft Stardrive T15,self-holding, with Cardan Joint, for QuickCoupling


Alternatively the screwdriver shaft with cardan joint may beused to insert the selected screw. Use the holding forceps toprovide axial force and stability.

Synthes 31



9Insert remaining screws and clamps

Repeat steps 4 – 8 to insert the remaining screws andclamps.

Note: A minimum of two clamps per rod is recommended.

10Insert second rod and remaining clamps and screws

Repeat steps 2 – 9 to insert implants on the contra-lateralsite.



11Final tightening

Instruments



Firmly tighten all occipital screws and occipital clamp setscrews using the screwdriver shaft with the handle withquick coupling.




Alternatively the screwdriver shaft with cardan joint may beused for final tightening all occipital screws and occipitalclamp set screws. Use the holding forceps to provide axialforce and stability.

Synthes 33


Occipito-Cervical Fixation withOcciput Rods(Shown in combination with Axon; can also be usedwith CerviFix or StarLock)


Recommended set

187.098 Axon

Insert bone screws and/or hooks to the cervical and upperthoracic spine as required by the patient’s pathology. Thetechnique is described in the Axon Technique Guide(036.000.179)

2Contour trial rod

Instruments

03.161.003 Occiput Trial Rod � 3.5 mm

Contour the occiput trial rod to fit the anatomy and to seatfully in the bone screws.



3Bend and cut occiput rod

Instruments



Contour the occiput rod using the bending pliers to matchthe curve of the occiput trial rod.



Synthes 35


4Drill pilot hole

Instruments






Drill to desired trajectory and depth using the drill bit and thedrill and tap sleeve. Drilling must occur through the occiputrod to ensure proper drilling depth.

Occipito-Cervical Fixation with Occiput Rods



5Measure hole depth

Instruments


Use the depth gauge to confirm hole depth and select thecorresponding screw length. The depth gauge must sit di-rectly on the bone.

Note: The depth gauge measures the working length, e.g. ifreading 10 mm on the depth gauge, select a 10 mm screw.

Synthes 37


1

2


6Tap

Instruments




Tap to desired depth using the tap and the drill and tapsleeve. Tapping must occur through the occiput rod to en-sure proper tapping depth.

Note: Tapping is recommended for all screws.




Set the tap depth by turning the tap sleeve to the desireddepth (1). Lock the tap sleeve by turning down the lockingnut until it contacts the tap sleeve (2). Finger tighten thelocking nut. Use the holding forceps to provide axial forceand stability. Tapping must occur through the occiput rod toensure proper tapping depth.



7Insert screw

Instruments




Note: An � 5.0 mm occipital screw may be used if the pri-mary screw has less than optimal fixation.




Alternatively use the screwdriver shaft with cardan joint toinsert the selected screw. Use the holding forceps to provideaxial force and stability.

Synthes 39



8Insert remaining screws

Repeat steps 4 – 7 to insert the remaining screws.

Note: A minimum of three screws per occiput rod isrecommended.

9Insert second occiput rod and corresponding screws

Repeat steps 2 – 8 to insert the second occiput rod andcorresponding screws.

Note: A minimum of three screws per occiput rod is recom-mended.



10Final tightening

Instruments



Firmly tighten all occipital screws using the screwdriver shaftwith the handle with quick coupling.




Alternatively the screwdriver shaft with cardan joint may beused for final tightening the occipital screws. Use the holdingforceps to provide axial force and stability.

Synthes 41



0123 036.

000.

755

SE_0

4424

7A

A50

0600

12©

Syn

thes

2006

Subj

ect

to m

odifi

catio

ns

Presented by:


Documents

Technique Guide - University of Iceland · The Synthes Occipito-Cervical Fusion System in combination with a Synthes posterior screw-rod system (e.g. Axon) is intended to provide