trident constrained acetabular inserts stability matters

Trident® Constrained Acetabular Inserts

Stability Matters

Trident® 0˚ Constrained Acetabular Insert

Trident® 0˚ All-Poly ConstrainedAcetabular Insert


Key Advantages

• Designed to decrease incidenceof dislocation

• Caters to a large range ofacetabular components

• Allows for greater intraoperativeefficiency and better patient matching

• Clinical history since 1989*

The information presented in this brochure is intended to demonstrate the breadth of Stryker product offerings. Always referto the package insert, product label and/or user instructions before using any Stryker product. Surgeons must always rely ontheir own clinical judgment when deciding which treatments and procedures to use with patients. Products may not beavailable in all markets. Product availability is subject to the regulatory or medical practices that govern individual markets.Please contact your Stryker representative if you have questions about the availability of Stryker products in your area.

The marks bearing the symbol TM are trademarks of Stryker.The marks bearing the symbol ® are registered trademarks of Stryker.

Literature Number: LTCAI-SS MC/GS 2.5M 09/06

Copyright © 2006 StrykerPrinted in USA

325 Corporate DriveMahwah, NJ 07430t: 201 831 5000

www.stryker.com

New Inserter Tip for Ease of Implantation

Paper References*Goetz et al., “Salvage of a Recurrently Dislocating Total Hip Prosthesis with Use of a ConstrainedAcetabular Component. A Retrospective Analysis of Fifty-six Cases.” J. Bone Joint Surg. Am,80:502-9, 1998.Bremner et al., “Use of Constrained Acetabular Components for Hip Instability: An Average 10-year Follow-up Study.” J. of Arthroplasty, Vol. 18 No. 7 Suppl. 1, 2003.

Trident® Constrained Acetabular Inserts

Benefits

• Utilizes patented Trident® locking mechanism

• Designed for cemented fixation into existingimplants or native acetabulum

• Provides for a range of intraoperative options

• Facilitates ease of femoral head insertion

Features

• Trident® 0˚,10˚, inserts

• All Poly cementable geometry

• Wide range of sizes accepts 22mm, 28mm,32mm femoral heads in 36mm, 42mm,46mm bipolar mechanism

• Unique locking mechanism inpre-assembled bipolar head

• Utilizes simple and efficient inserter tip

Trident® Acetabular Systems Options

Trident® CeramicInserts†

Trident® X3® Polyethylene Inserts Trident® Crossfire®Polyethylene Eccentric Inserts

Trident® Elevated RimInserts Trident® Constrained

Inserts

AluminaCeramic Heads†

Biolox® deltaCeramic Heads††

LFIT™ Ion ImplantedCoCr Heads††

† NOTE: The Trident® Alumina Ceramic inserts must beused with Stryker® Orthopaedics Alumina Ceramic heads.

†† Only cleared for use with polyethylene inserts.

Constrained Acetabular InsertSurgical Protocol

Trident®

Trident®

Constrained Acetabular InsertSurgical Protocol

Table of Contents

Introduction 1

Stryker Trident® Constrained Acetabular Insert 1

Cementless OptionsPrimary Surgery 3Revision Surgery 3Revising the Metal Shell 3Retaining the Metal Shell 3

Trial Evaluation 3

Component Selection 3

Implantation 3

Femoral Bearing Head / Insert Assembly 4

Constrained Insert Removal 4

Cementable Options 5

Trident® Constrained Acetabular

Insert Trials 6

Postoperative Care, Indications,

Contraindications and Warnings 8

1

Acetabular Shell (Metal)

Outer Bearing UHMWPEThickness

Insert (UHMWPE)

Bipolar Outer FemoralHead (CoCr)

Bipolar Retaining RingUHMWPE

Locking Ring(Titanium Alloy)

Bipolar UHMWPEInsert

Trident® ConstrainedAcetabular Inserts



Trident® 0˚ All-Poly Constrained Acetabular Insert

Introduction

The Trident® Constrained AcetabularInsert is indicated for use in primaryand revision total hip patients whoexhibit a high risk of hip dislocation.It should be used when moreconservative methods of soft tissuemanagement, such as lengthening thefemoral neck or lateralizing the joint’scenter of rotation, are insufficient forrestoring joint stability.

The Trident® Constrained AcetabularInsert offers less range of motion from standard total hip replacementcomponents but can be a better solutionwhen the likelihood of dislocation ishigh.

Trident® ConstrainedAcetabular InsertThe Trident® Constrained AcetabularInsert is designed specifically for theStryker UHR® bipolar head.The bipolar head is preassembled in the insert and securely retained by a titanium alloy retaining ring. TheTrident® 0˚ and 10˚ ConstrainedAcetabular Inserts can only be used in a Trident® Acetabular Shell.

The Trident® 0˚ All-Poly ConstrainedInsert can be cemented into an existingshell or cage device, or directly into theacetabulum.

Articulation occurs at both the femoralhead-to-bipolar interface and at thebipolar-to-insert interface.

A unique, patented split-ring lockingmechanism facilitates ease of femoralhead assembly, yet provides the potentialfor enhanced protection againstcomponent disassembly.

A head removal key allows for easy, non-destructive componentdisassembly.

A dynamic valgus alignment creates a constant neutral alignment of thebipolar within the insert during weightbearing to provide increased headcoverage. This prevents inner bearingarticulation from occurring on thelocking mechanism, thus sparing themechanism from extreme loading.

2

*The alphabetical letter at the end of a Trident® catalog number identifies compatibility among all Trident® acetabular components.**NOTE: Special Key for 690-00-22D, 690-00-22E and 690-10-22E, 690-10-22F, 69-2244,69-2246, 69-2248 only.***Values calculated using Accolade® TMZF Size 3 stems.

Table 2: Trident® 10˚ Constrained Inserts

Trident®Trident® Bipolar

BipolarOuter Bearing

TotalOuter Bearing Insert

AlphaConstrained Femoral

Head ODUHMWPE

Range ofOD Spherical Head Removal Trial

Code*Insert Head Size

(mm)Thickness

Motion***Diameter Key Catalog Catalog

Catalog No. (mm) (mm) (mm) Number No.

E 690-10-22E 22 36 7.9 82° 44.4 HI-UHRK-3638** 2230-22E

F 690-10-22F 22 36 9.9 82° 48.4 HI-UHRK-3638** 2230-22F

G 690-10-28G 28 42 8.4 90° 51.5 HI-UHRK-28 2230-28G

H 690-10-28H 28 42 10.2 90° 55.0 HI-UHRK-28 2230-28H

I 690-10-28I 28 42 11.6 90° 58.0 HI-UHRK-28 2230-28I

J 690-10-28J 28 42 13.7 90° 62.0 HI-UHRK-28 2230-28J

Table 3: Trident® 0˚ All-Poly Constrained Inserts

Trident® BipolarBipolar

Outer BearingTotal Outer Bearing Head Removal

Constrained FemoralHead OD

UHMWPERange of OD Spherical Key Catalog

Insert TrialInsert Catalog Head Size

(mm)Thickness

Motion*** Diameter (mm) NumberCatalog No.

No. (mm) (mm)

69-2244 22 36 7.3 82° 44.0 HI-UHRK-3638** 1090-2244

69-2246 22 36 8.3 82° 46.0 HI-UHRK-3638** 1090-2246

69-2248 22 36 9.3 82° 48.0 HI-UHRK-3638** 1090-2248

69-2850 28 42 7.3 90° 50.0 HI-UHRK-28 1090-2850

69-2852 28 42 8.3 90° 52.0 HI-UHRK-28 1090-2852

69-2854 28 42 9.3 90° 54.0 HI-UHRK-28 1090-2854

69-3256 32 46 8.3 94° 56.0 HI-UHRK-32 1090-3256

69-3258 32 46 9.3 94° 58.0 HI-UHRK-32 1090-3258

69-3260 32 46 10.3 94° 60.0 HI-UHRK-32 1090-3260

Table 1: Trident® 0˚ Constrained Inserts

Trident®Trident® Bipolar

BipolarOuter

TotalOuter

Head RemovalAlpha

Constrained FemoralHead OD

UHMWPERange of

OD SphericalKey Catalog

Insert

Code*Insert Catalog Head Size

(mm)Thickness

Motion***Diameter

NumberCatalog No.

Number (mm) (mm) (mm)

D 690-00-22D 22 36 5.6 82° 40.4 HI-UHRK-3638** 2270-22D

E 690-00-22E 22 36 7.5 82° 44.4 HI-UHRK-3638** 2270-22E

F 690-00-28F 28 42 6.5 90° 48.5 HI-UHRK-28 2270-28F

G 690-00-28G 28 42 8.1 90° 51.5 HI-UHRK-28 2270-28G

H 690-00-32H 32 46 7.8 94° 55.0 HI-UHRK-32 2270-32H

I 690-00-32I 32 46 9.3 94° 58.0 HI-UHRK-32 2270-32I

J 690-00-32J 32 46 11.3 94° 62.0 HI-UHRK-32 2270-32J

3

Cementless Options

Primary Surgery:

When used in a primary surgery, theStryker femoral and Trident® metal shellcomponents should be implanted inaccordance with the applicable SurgicalProtocols. However, if an uncementedmetal shell is being implanted with theTrident® Constrained Acetabular Insert,supplemental fixation, with a minimumof two (2) bone screws, is recommended.

Revision Surgery:

When the Trident® ConstrainedAcetabular Insert is chosen for use in the revision of a Trident® AcetabularComponent, the existing Trident® insertshould be removed in accordance withthe appropriate Stryker SurgicalProtocol.

Care should be taken not to mar theinterior of the existing metal shell whenremoving the insert. The stability ofthe metal shell and the locking barbsmust be assessed for any damage. Also,remove any tissue that may get wedgedbetween the insert and shell lip.

Revising the Metal Shell:

If the shell requires replacement due to instability, bone loss, damage to the locking ring groove, or any othercondition, the metal shell may bereplaced with a Stryker Trident® shell in accordance with the appropriateSurgical Protocol. If an uncementedmetal shell is being implanted with theTrident® Constrained Acetabular Insert,supplemental fixation, with a minimumof two (2) bone screws, is recommended.

Retaining the Metal Shell:

Once the integrity of the existing metal shell is established, remove anymembranes from the screw holes andinside the shell. Also remove any tissuethat may impinge the poly engagementat the periphery of the metal shell.

Trial EvaluationThe appropriate size Trident®Constrained Trial Insert is selected toevaluate joint mechanics (Figure 1).Refer to the trial table on page 6 for the appropriate size trial insert. TheTrident® Constrained Trial Insertscontain a screw mechanism to securethe trial to the acetabular shell. The

trial insert is inserted into the Trident®Acetabular Shell and the screwmechanism must be tightened by usingthe Stryker Torx® Screw Drivers. Oncethe trial insert is fully seated, the trialreduction can be performed. Once thetrial reduction is performed, remove the trial insert.

Component SelectionSelect the appropriate sized Trident®Constrained Acetabular Insert bycorrelating the insert letter designation(alpha code) with that of the shell (See Tables 1 & 2 on page 2).

ImplantationFor proper seating and locking of theconstrained insert, the insert must beboth rotationally and axially aligned to the acetabular shell prior to finalimpaction. While holding the insert inyour fingers, rotationally align the insertlocking grooves to the barbs of the shellmaking sure the location of the 10° lipmatches that of the trial insert.

Once the insert is rotationally aligned,press the insert into the shell whilekeeping the axis of the insert parallel to the axis of the shell (Figure 2).

Push the insert into the shell until theinsert will not go any further. Care mustbe taken not to rock, tilt, or misalign theinsert prior to final impaction, as thismay damage the polyethylene lockingbead thus preventing proper seating and locking.

Locking of the Trident® ConstrainedAcetabular Insert into the appropriatelysized Trident® metalshell is the same asstandard Trident®AcetabularPolyethylene Inserts.The constrained insert,however, cannot beimpacted into the shellwith the StrykerAcetabular Cup InsertImpactor (2101-0130).

Locking Insert intoShell

Select theConstrained LinerInserter/ImpactorTip (2199-20xx)that corresponds tothe femoral headsize (Figure 3).Thread the tip ontothe Trident CupPositioner/Impactorhandle (2101-0200, Figure 4) andinsert the tip into the bipolar (Figure5). Impact the insert to its finalseating with the force and instrumentperpendicular to the shell face. Checkfor proper seating by assuring that theperiphery of the insert is in contactwith the shell, circumferentially.

Figure 2 (10˚ insert shown)

Figure 3 Figure 5

Figure 1

Figure 4

4

and a round bullet tip. Rotate thebipolar component within the cupinsert to allow the drill access to themedial wall of the insert. Using a 3.3mmdrill bit, create a hole slightly off-centerof the medial wall of the insert. Cautionshould be taken to avoid drillingthrough the dome hole of the metalshell. The deepening of this hole shouldbe stopped before contact is made withthe inner surface of the metal shell.

The appropriately-sized bone screw is started into the drill hole (a 35mmscrew length or longer is recommended).Advance the screw until the tip contactsthe inner surface of the metal shell.Continued advancement of the screwlevers the cup insert from its seatedposition. Once the cup insert has beenlifted from its fully-seated position bythe bone screw, additional distractiveforce may be applied with an elevator or osteotome.

If access to the medial wall of the insertis unattainable, the titanium alloyretaining ring on the outer rim of theacetabular insert may be removed usingan osteotome and/or forceps. Insertremoval may proceed as indicated above,only in the area of the outer rim ofthe insert.

The cup insert may also be removed byutilizing an osteotome, elevator and/orforceps at the cup insert/metal shelljunction, to pry the insert from itslocked position within the cup shell.

Table 4:

Femoral Head Compatibility with Stryker Trident® Constrained Insert

Femoral Head Component Catalog Number Series CoCr Morse Taper 1001-XXXXCoCr C-Taper 6001-XXXXCoCr/LFIT™ Morse Taper 01-XXXX and S-1399-HHXXCoCr/LFIT™ C-Taper 06-XXXX and S-1400-HHXXAlumina C-Taper 17-XXXXEZirconia Ceramic C-Taper 16-XXXXDelta Ceramic C-Taper 18-XXXXModified V40™ CoCr 6260-4-XXX and 6260-5-XXXCoCr/LFIT™ V40™ 6260-9-XXXZirconia V40™ 6364-4-XXXAlumina V40™ 6260-7-XXX and 6565-0-XXXDelta Ceramic V40™ 6570-0-XXXPCA® CoCr +15mm 2284-0-XXXModified PCA® CoCr 6280-0-XXXPCA® Zirconia 6284-3-XXX

WARNING: V40™ femoral heads (catalog number series 6264-4-XXX and 6264-5-XXX) and PCA® femoral heads (catalog number series 6284-0-XXX) are NOT compatible with Stryker UHR® Bipolar and Constrained Acetabular Inserts.

Femoral Bearing Head/InsertAssembly

After assembly of the constrained insertinto the metal shell, the head of theimplanted femoral stem is positioned on the opening of the constrainedinsert’s bipolar component. If utilizing a femoral stem with a modular femoralhead, the modular femoral head must be fully seated onto the femoral stemtrunnion prior to assembly with theTrident® Constrained Acetabular Insert(See Table 2 for head compatibility).The bipolar component’s opening must be fully visible before introducingthe femoral bearing head into thecomponent.

Reduce the stem in the standard fashion by elevating the patient’s leg and applying a slight downward forceuntil the head snaps into the bipolarcomponent. The bipolar component has a positive locking mechanism whichenables the bipolar and femoral head tobe assembled with less than five poundsof force. The locking mechanismconsists of a split polyethylene ringwhich is captured within the bipolar’spolyethylene insert. As the femoral headis inserted into the bipolar, the assemblyload forces the expansion of the splitring within the bipolar. Upon clearingthe maximum diameter of the head, the

ring contracts to its normal diameter,resulting in the entrapment of the headwithin the bipolar.

Once the joint is reduced, the femoralhead is retained within the constrainedinsert and can be removed only throughuse of a Stryker UHR® Head RemovalKey.

Use of the Head Removal Key

Insert the Head Removal Key into theinner bearing area between the bipolarcomponent and the Threaded TrialHead of the Impactor/Extractor andpush upward toward the UHR® headcenter. This spreads the locking ringwithin the UHR® component. With agentle pulling action, remove the Impactor/Extractor Handle assembly and the keyfrom the constrained insert at the same time.

Constrained Insert RemovalRemoval of the constrained acetabularcup insert, if necessary, may beaccomplished using a 3.3mm drill bit and a self-tapping bone screw with3.4mm or higher major thread diameter

Figure 6 Head Removal Key

5

Cementable Options

Option 1:

Cementing into an ImplantedShell or Cage:

Following the fixation of a shell or cagedevice, a Trident® All-Poly ConstrainedInsert may be cemented into the device.

Trialing

To assess head center placement, a trialreduction may be performed by usingthe appropriate Trident® All-PolyConstrained Trial Insert and head trialto assess joint mechanics and appropri-ate head center placement. Refer to thetrial table on page 6 for the appropriatesize trial insert. The Trident® All-PolyConstrained Trial Inserts contain ascrew mechanism to secure the trial to a shell or cage with compatible domehole threads. The screw mechanismmust be tightened using the StrykerTorx Screwdrivers.

NOTE: The insert trials are the samesize as the actual implant, and do nottake into account a cement mantle.

Cementing and Inserting Implant

Once trial reduction is complete, theinsert can now be cemented in place(see Table 3 on page 2). Thread theConstrained Liner Inserter/ImpactorTip onto the Trident® Cup Impactorhandle. Mount the selected Trident®All-Poly Constrained Insert on theinserter tip (Figure 5 on page 3). Placethe anteversion rod in the correct posi-tion. Mix one pack of Simplex™ bonecement according to the manufacturer’sspecifications and lavage the inside of

the cup shell. Dry thoroughly prior tothe introduction of the bone cement.The cement is mixed and is insertedinto the acetabulum in bolus form.Once it has achieved a doughy state,the insert, mounted on the inserter tip,is then pressed gently into the cup anddriven deeply into the bed of cement.The angle guide allows assessment ofproper cup position, which is typically40 to 45 degrees of abduction or lateralopening and 10 to 20 degrees of antev-ersion.

NOTE: When determining the properangulation of the insert, it is importantto critically evaluate the anatomic landmarks and patient anatomy foroptimum placement.

It is essential that the insert be com-pressed into the cup and the introducerheld as still as possible until cement hashardened. After the cement is cured,the insert introducer is then carefullyremoved from the insert. Take specialmeasures to remove all excess bonecement from the edges of the cup byutilizing curettes and osteotomes.

Head Assembly

Go back to page 4 and proceed with the instructions for final implant headassembly.

Option 2:

Cementing into the Acetabulum:To cement the Trident® All-PolyConstrained Insert directly into theacetabulum, the bone must first beproperly prepared. This is done throughspherical acetabular reaming.

Reaming

Acetabular reaming is initiated with a reamer size that fits easily into thesocket. This allows reaming based onthe anatomic center of the acetabulum.Initial reaming should be carried out to identify the medial wall. Reamingshould medialize the socket to thispoint but care should be taken not tocompromise or violate the medial wall.

NOTE: If too small a reamer is chosento begin with, the reaming process may begin eccentrically, thus removingexcessive anterior or posterior wall bone

stock with resultant non-anatomicplacement of the acetabular component.

The low profile design of the CuttingEdge™ Spherical Reamer necessitatesthe need to ream to the full depth. Thereamer head should be driven to thepoint where the rim/cross bar contactsthe acetabular wall at the peripherallunate region. Removal of the reamerfrom the handle is performed by pullingback on the locking sleeve and rotatingthe reamer head a quarter-turn in aclockwise direction.

NOTE: Care should be taken not toenlarge or distort the acetabulum byeccentric reaming. Final acetabularreaming ideally shows the hemisphericalacetabulum denuded of cartilage, withthe subchondral plate preferably intact,and the anterior acetabular wall pre-served.

It is believed that the subchondral platefunctions as an important load-sharingand support mechanism. Preserving asmuch of the subchondral plate as possi-ble may help preserve the qualities ofthe bone/metal composite.

Reaming should be done to the desiredimplantation size.

NOTE: It is recommended to have a2mm cement mantle, so 4mm should be added to the respective TridentConstrained Insert Outer Bearing ODSpherical Diameter (see Table 3 on page2) to equal the implantation size (i.e.,if you ream to 56mm, add cement andimplant the insert with a 52mm OD).

NOTE: The Cutting Edge™ SphericalReamers are very aggressive and per-form best when sharp. Care should betaken to protect the reamer fromunnecessary handling, as dull or dam-aged cutting teeth may cause improperreaming. Dull cutting teeth will resisthard bone and will deflect to cut softerbone. This situation may result in anirregularly shaped or enlarged acetabu-lum preparation.

Cement Fixation Holes

After completion of reaming, fixationholes may be made in the subchondralplate. These can be made with a flexibledrill and drill guide provided in theinstrument set, a curette, or a power

Figure 7

6

bur. A single primary fixation holeshould be created in each of three areas:the acetabular dome, ischial ramus, andpubic ramus. Additional holes can becreated at the surgeon’s discretion.

Trialing

Trialing can be accomplished by usingthe respective Insert Trial. The inserttrials are the same size as the actualimplant and do not take into accountthe cement mantle. The trials shouldalso be used to assess the fit and esti-mate final orientation of the cup priorto implantation.

NOTE: To maintain a 2mm cementmantle, a trial 4mm greater than thefinal implant may be used to assessreaming depth. Take care to note theassociated head size of the larger trial.

Cementing and Inserting Implant

Once trial reduction is complete, theinsert can now be cemented in place.Thread the Constrained Liner Inserter/Impactor Tip onto the Trident® CupImpactor handle. Mount the selectedTrident® All-Poly Constrained Insert on the inserter tip. Place the anteversionrod in the correct position. Mix onepack of Simplex™ bone cement accord-ing to the manufacturer’s specificationsand lavage the inside of the acetabulum.Dry thoroughly prior to the introduc-tion of the bone cement. The cement ismixed and is inserted into the acetabu-lum in bolus form. Once it has achieveda doughy state, the insert, mounted onthe inserter tip, is then pressed gentlyinto the cup and driven deeply into thebed of cement. The angle guide allowsassessment of proper cup position,which is typically 40 to 45 degrees of

abduction or lateral opening and 10 to 20 degrees of anteversion.

NOTE: When determining the properangulation of the insert, it is importantto critically evaluate the anatomic landmarks and patient anatomy foroptimum placement.

It is essential that the insert be com-pressed into the acetabulum and theinserter held as still as possible untilcement has hardened. After the cementis cured, the inserter tip is then carefullyremoved from the insert. Take specialmeasures to remove all excess bonecement from the edges of the cup by utilizing curettes and osteotomes.

Femoral Bearing Head/InsertAssembly

See page 4 for the instructions to per-form the final implant head assembly.

Trident® Constrained Acetabular Insert Trials

Trident® 0˚ Insert Trials Trident® 10˚ Insert Trials Trident® All-Poly Insert Trials

2270-22D 2230-22D 1090-2244

2270-22E 2230-22E 1090-2246

2270-28F 2230-28F 1090-2248

2270-28G 2230-28G 1090-2850

2270-32H 2230-28H 1090-2852

2270-32I 2230-28I 1090-2854

2270-32J 2230-28J 1090-3256

1090-3258

1090-3260

Drivers (included in Bone Screw Tray)

Straight Driver Shaft 2107-1014

Universal Driver Shaft 2107-1015

Flexible Driver Shaft 2107-1016

Straight Driver Shaft - 6" 2107-1017

Captive Twist Straight Driver Shaft 2107-2014

Ratchet Handle for Drivers 2107-1000

Trident® Constrained Acetabular Inserts utilize theCutting Edge™ Bone Screw Tray and Acetabular Reamer Tray

7

Additional Required Instruments

Femoral Stem Head Impactor 1104-1000

Head Removal Key 22MM Inner Diameter HI-UHRK-3638



Trident Cup Impactor 2101-0200

Constrained Liner Inserter/Impactor Tip 2199-2022



Optional

Acetabular Trial Insert Containment Screw-Kit (5/kit) 2230-0010

(Containment Screw Kit is optional - screws come pre-assembled with the Eccentric and Constrained Trial inserts)

All-Poly Constrained Insert Trial Screw 1090-2000

(Screws come pre-assembled with the All-Poly Constrained Trials)

Cases and Trays

Trident 0˚ and All-Poly Constrained Insert Trial Tray/Case 2402-3020Trident 0˚ and All-Poly Constrained Insert Trial Lid 2402-3090

Double Tier Case 8000-0200Single Tier Case 8000-0100Trident 10˚ Constrained Insert Trial Tray 2402-1100

The system provides the option of either a Single Tier or Double Tier Case.The Double Tier Case accommodates both the 10˚ Constrained Insert Trial Trayand the Eccentric Insert Trial Tray.

with Trident® metal acetabular shells.The Trident® All-Poly ConstrainedInserts can be cemented directly into aGAP Cup, GAP Ring, Trident® metalacetabular shell, or directly into theacetabulum. The assembled acetabularcomponent is used in conjunction withany appropriately sized HowmedicaOsteonics stem of compatible head size,to achieve total reconstructivereplacement of the hip joint.

8

Postoperative Care,Indications,Contraindications andWarningsDescription

The Stryker Trident® ConstrainedAcetabular Insert is comprised of twopreassembled components: an outerinsert component and a capturedUHR® (Universal Head) component.The UHR® component is comprised of an outer shell into which a bearinginsert has been permanentlyassembled. The UHR® bearing inserthas a factory assembled UHMWPEretention ring. The outer acetabularinsert has a Titanium alloy retainingring which retains the UHR® head inthe plastic portion of the insert and aCoCr alloy circumferential locking wirefor secure assembly of the insert to the metal shell. With the exception of theTrident® All-Poly Constrained Inserts,the Stryker Trident® ConstrainedAcetabular Inserts are designed to be assembled with Trident® metalacetabular shells. The Trident® All-PolyConstrained Acetabular Inserts can be cemented directly into a GAP Cup,GAP Ring, Trident® metal acetabularshell, or directly into the acetabum.The assembled acetabular component is used in conjunction with anyappropriately sized stem of compatiblehead size, to achieve total reconstructivereplacement of the hip joint. Please notethe following:

Materials:

• ASTM F-75 -cobalt chromium alloyUHR® outer shell

• ASTM F-648 -ultra-high molecularweight polyethylene(UHMWPE) UHR®bearing insert,Acetabular bearing insert body, UHR®retention ring

• ASTM F-136 -Titanium 6Al-4V ELIalloy retaining ring

Description

Trident® Constrained Acetabular Insertis comprised of two pre-assembledcomponents: an outer insertcomponent and a captured UHR®(Universal Head) component. TheUHR® component is comprised of an

outer shell into which a bearing inserthas been permanently assembled. TheUHR® bearing insert has a factoryassembled UHMWPE retention ring.The outer acetabular insert has a Tialloy retaining ring which retains theUHR® head in the plastic portion ofthe insert. With the exception of theTrident® All-Poly Constrained Inserts,the Trident® Constrained AcetabularInserts are designed to be assembled

Materials

The devices are manufactured from materials that meet the following ASTMStandards:

Cast CoCr Alloy ASTM F-75 UHR® outer shell bearing insert

Ultra-High Molecular ASTM F-648 UHR® bearing insert,Weight Polyethylene Acetabular bearing insert body,(UHMWPE) UHR® retention ring

Titanium 6Al-4V ELI Alloy ASTM F-136 Retaining ring

Warnings

• Closed reduction of a dislocation ofthis device is not possible. Patientsshould be made aware that treatmentof device dislocation will requireadditional surgery.

• Patients should be instructed on theimpact of excessive loading that canresult if the patient is involved in anoccupation or activity which includessubstantial walking, running, lifting,or excessive muscle loading due topatient weight causing extremedemands on the constrained insertcan result in the failure of the device.Extreme demands on the device mayalso compromise the acetabular shell’sfixation in the acetabulum.

• The UHMWPE UHR® retention ring and Ti alloy retaining ring ofthe constrained insert should not be handled or removed as they arecritical to the security of theassembly. Alteration of the factorypreassembled device can result inimproper function of the retainingmechanisms. Discard or return tomanufacturer any constrained insertif the retaining mechanisms appeardamaged or mishandled.

Compatibility

• Howmedica Osteonics ConstrainedAcetabular Inserts are compatiblewith all Howmedica Osteonicsfemoral heads except old-style V40head catalog number series 6264-4-XXX and 6265-5-XXX and old-styleP.C.A. head catalog number series6284-0-XXX.

Indications

• The Trident® Constrained AcetabularInsert is indicated for use as acomponent of a total hip prosthesis in primary and revision patients athigh risk of hip dislocation due to ahistory of prior dislocation, bone loss, joint or soft tissue laxity,neuromuscular disease, orintraoperative instability.

Contraindications

• Bone or musculature compromisedby disease, infection or priorimplantation, which cannot provideadequate support or fixation for the prosthesis.

• Infection in or about the hip joint.

• Skeletal immaturity.

9

• Improper alignment of the acetabularinsert within the acetabular shellprior to impaction may result inimproper seating of the constrainedacetabular insert.

• Removal of the constrained insertafter its assembly into the metal shellresults in the destruction of theinsert. Discard any device removedafter the locking mechanism has beenengaged, do not reinsert the device.

• Care should be taken not to nick ornotch the inner surface of the metalshell during insert removal, whichcould lead to premature wear of theUHMWPE.

• Old style V40™ femoral head catalognumber series 6264-4-XXX and 6264-5-XXX and old style P.C.A.®Femoral Head catalog number series6284-0-XXX are not compatible withthe UHR® Bipolar and ConstrainedAcetabular Insert.

• Do not substitute anothermanufacturer’s device for anycomponent of the HowmedicaOsteonics total hip system. Any such use will negate the responsibilityof Howmedica Osteonics for theperformance of the resulting mixedcomponent implant.

• Never reuse an implant, even though it may appear undamaged.

• Discard damaged, mishandled,or contaminated implants.

• See the Patient CounselingInformation Section for moreinformation.

Precautions

• Protect all components fromcontamination.

• Do not allow coated surfaces tocontact cloth or other fiber-releasingmaterials.

• Protect polished bearing areas andmachined taper surfaces from contactwith hard or abrasive surfaces.

• Take care not to cut through surgicalgloves when handling any sharp-edged orthopaedic device.

Patient Selection

• Proper implant selection is critical to the stability and longevity ofthe acetabular implant in hiparthroplasty. Proper implantselection must consider design,fixation, and environmental variablesincluding patient weight, age, bonequality and size, activity level andpre-operative level of health, as wellas the surgeon’s experience andfamiliarity with the device. Longevityand stability of the implant may beaffected by these factors.

• Patients with high-activity levelsand/or higher weight patients are atgreater risk for implant complicationsor failures. For patients with poorproximal bone quality, the use ofsupplemental adjunctive proximalfixation/support is advised forimplant stability.

• The surgeon must evaluate eachsituation carefully based upon the patient’s clinical presentationbefore making any decisionsregarding the selection of the implant.

Adverse Effects

• Dislocation of the hip prosthesis can occur due to inappropriatepatient activity, trauma or otherbiomechanical considerations.

• Loosening of total hip componentscan occur. Early mechanical looseningmay result from inadequate initialfixation, latent infection, prematureloading of the prosthesis or trauma.Late loosening may result fromtrauma, infection, biologicalcomplications, including osteolysis,or mechanical problems, with thesubsequent possibility of boneerosion and/or pain.

• Fatigue fracture of femoral stems has occurred in a small percentage of cases. Stem fracture is more likelyto occur in heavy, physically activepatients, or when contralateral jointdisability results in a disproportionatedistribution of weight on thereconstructed joint.

• Wear of polyethylene componentsmay occur. Polyethylene wear hasbeen associated with bone resorption,loosening, and infection.

• Peripheral neuropathies, nervedamage, circulatory compromise,and heterotopic bone formation may occur.

• Serious complications may beassociated with any total jointreplacement surgery. Thesecomplications include, but are notlimited to: genitourinary disorders,gastrointestinal disorders, vasculardisorders including thrombus,bronchopulmonary disordersincluding emboli, myocardialinfarction, or death.

• Acetabular pain may occur due to loosening of the implant.

• Intraoperative fissure, fracture, orperforation of the femur, acetabulum,or trochanter can occur due toimpaction of the component intothe prepared femoral canal oracetabulum. Postoperative femoral or acetabular fracture can occur dueto trauma, the presence of defects,or poor bone stock.

• Asymptomatic, localized progressivebone resorption (osteolysis) mayoccur around the prostheticcomponents as a consequence of foreign-body reaction to theparticulate matter of cement, metal,ultra-high molecular weightpolyethylene (UHMWPE) and/orceramic. Particulate is generated byinteraction between components,as well as between components and bone, primarily through wearmechanisms of adhesion, abrasionand fatigue. Secondarily, particulatecan also be generated by third-bodywear. Osteolysis can lead to futurecomplications, including loosening,necessitating the removal andreplacement of prostheticcomponents.

• Very small particles from metal andpolyethylene components can be shedfrom the components during normaluse and over time. Although most ofthis debris stays in the relevant joint(i.e., contained in the synovium) or is trapped by surrounding scar tissue,microscopic particles can migratethroughout the body and onoccasions have been described asaccumulating in lymph nodes andother parts of the body. Although no significant medical complications

have been reported as a result of theseparticles, their migration and/oraccumulation in the body have beendescribed in the literature. Given the insufficient time period duringwhich patients with these deviceshave been followed and the fact thatthese devices are currently being usedin younger patients and remain in thebody for increasingly longer periodsof time, it should be said that thelong-term effects, if any, from theseparticles, are unknown. The long-term effects have been theorized toinclude:

• Cancer: There is presently noscientific evidence that links metallicor polyethylene debris with cancer.However, the possibility cannot beruled out.

• Lymphadenopathy and Accumulationin Other Tissues/Organs: There have been a few reports of theaccumulation of wear debris in lymph nodes (proximate and distal).Although no medical complicationsor disease process has been reported as stemming from theseaccumulations, their existence shouldbe recognized to facilitate diagnosisand avoid confusion with suspiciouslesions, cancerous or otherwise.

• Systemic Disease: There has beensome speculation that there could be an association between migrationof debris and as yet unidentifiedsystemic effects. Long-term effectsmay be demonstrated at some pointin the future, but because there is very little scientific data suggestingassociation between migration ofdebris and systemic disease, it isbelieved that the benefits of thesedevices clearly outweigh the potentialrisks for any such theoretical long-term effect.

• Metal sensitivity reactions have beenreported following joint replacement.

• Undesirable shortening or lengtheningof the limb.

• Infection can occur.

• Adverse effects may require medicalintervention including reoperation,revision, arthrodesis of the involvedjoint, Girdlestone, or amputation ofthe limb.

Use and Implantation

• Before clinical use, the surgeonshould thoroughly understand allaspects of the surgical procedure and limitations of the device.

• The Surgical Protocol for theappropriate Howmedica Osteonicship system provides additionalprocedural information.

• Radiographic templates are availableto assist in the preoperativeprediction of component size andstyle.

• Specialized instruments are availableand should be used to ensure accurateimplantation of prostheticcomponents.

• To preserve the integrity of the actualimplants and their sterile packaging,use the recommended trialcomponents for size determination,trial reduction and range-of-motionevaluation.

• Proper selection, placement, andfixation of the implant componentsare critical factors affecting implantservice life. The durability ofprosthetic implants is affected bymany biologic, biomechanic andother extrinsic factors that limit their service life. Accordingly, strictadherence to the indications,contraindications, precautions andwarnings for this product is essentialto potentially maximize service life.

Information for the Patient

• Advise patients of the limitations ofthe reconstruction and the need toprotect the implant from full weightbearing until adequate healing hasoccurred.

• Caution patients to protect thereplaced joint from excessive loading,and to follow the physician’sinstructions regarding activity level,follow-up care, and treatment. Advisepatients that the device cannot beexpected to withstand indefinitely thesame activity levels and loads as anormal healthy joint, that the implantcan break or become damaged as aresult of excessive loading, and thatthe device has a finite service life andmay need to be replaced in the future.

• Warn the patient of surgical risks and possible adverse effects.

• Dental procedures, endoscopicexaminations and other minorsurgical procedures have beenassociated with transient bacteremia.Instruct the patient to inform theirdoctors that they have an artificial hipreplacement, so that their doctors can decide whether to use antibioticprophylaxis for such procedures.

How Supplied

• These products have been sterilizedby gamma radiation.

• Do NOT resterilize.

• Take care to prevent contamination of any components

• Inspect the packaging of sterileproducts for flaws before opening.In the presence of any flaws, assumethat the product is nonsterile.

• Discard ALL nonsterile orcontaminated products.

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Notes:

Notes:

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The information presented in this brochure is intended to demonstrate the breadth of Stryker product offerings. Alwaysrefer to the package insert, product label and/or user instructions before using any Stryker product. Surgeons must alwaysrely on their own clinical judgment when deciding which treatments and procedures to use with patients. Products may notbe available in all markets. Product availability is subject to the regulatory or medical practices that govern individual mar-kets. Please contact your Stryker representative if you have questions about the availability of Stryker products in your area.

The marks bearing the symbol TM are trademarks of Stryker.The marks bearing the symbol ® are registered trademarks of Stryker.

Literature Number: LSP44 Rev. 1 MS/GS 2.5m 07/06

Copyright © 2006 StrykerPrinted in USA

325 Corporate DriveMahwah, NJ 07430t: 201 831 5000

www.stryker.com

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