introduction restoring depuy mitek, inc. is designed to

RestoringAnatomic ACLFootprint

the

Improved ACL FootprintPlacement & Coverage*

By utilizing a patented sheath and screwdesign that spreads the graft around theperimeter of a single tunnel.

Controlled AM & PL BundlePositioning

Offers distinct bundle separation ina single tunnel.

Soft Tissue InterferenceAperture Fixation

Provides average pullout strength of804N with less than 1mm elongation.***

INTRODUCTION

The new Femoral INTRAFIX® ACL Fixation System fromDePuy Mitek, Inc. is designed to provide soft tissue femoralfixation for ACL reconstruction surgery using a single tunnelthrough an anteromedial approach with the use of eitherallograft or autograft. Femoral INTRAFIX, with its uniquepatented polypropylene sheath and PEEK screw implant de-sign offers a new technique to achieve a more anatomic ACLreconstruction with improved femoral footprint placementand coverage, controlled anteromedial (AM) and postero-lateral (PL) bundle positioning, and strong, stiff soft tissueaperture fixation*.

The current trend in ACL reconstruction techniques is tomore closely restore the anatomical footprint and kinemat-ics of the ACL through a more laterally (“lower”) positionedfemoral tunnel, which replaces portions of both the AM andPL bundles**.1,2,5,10,11 Femoral INTRAFIX achieves this re-sult using an anteromedial portal to accurately position asingle tunnel in the center of the femoral ACL footprint.Femoral INTRAFIX also creates an hourglass shaped foot-print by separating and controlling the positioning of thegraft strands toward the native location of the AM and PLbundles. The anteromedial approach allows flexibility inplacing the femoral tunnel independent of the tibial tunneland eliminates a preventable error of an excessively verticaltunnel position commonly seen with a transtibial ap-proach.1,4

It has been reported that kinematics of the reconstructedknee are strongly affected by the location of the tibial andfemoral tunnels. Biomechanical tests of cadaveric recon-structions demonstrate nearly normal knee kinematics whenthe tibial tunnel is close to the center of the tibial footprintand the femoral tunnel is placed in the center of thefemoral footprint.4-9 In addition, studies have reported thata lateralized tunnel placed lower in the notch and drilled inthe center of the ACL femoral footprint can effectively re-place approximately half of the AM bundle and PL bundlefootprints.10

To further address all the components of an anatomic ACLreconstruction, the shape of the footprint also needs to beevaluated. The native ACL footprint is not circular, and hastwo distinct regions for the AM and PL bundles. In contrastto other femoral fixation devices, Femoral INTRAFIX allowsthe strands of a soft tissue graft to be clustered into anhourglass configuration rather than a cylinder.2 Harner etal.3 reported insertional areas up to 3.5 times larger thanthe midsubstance of the ligament indicating that the colla-gen is spread around the perimeter of the insertion. Toachieve the goal of anatomic reconstruction, Femoral IN-TRAFIX fixates the AM and PL bundles in the shape of anhourglass, closely resembling the shape of the native ACLfootprint with the collagen segregated into two bundlesaround the perimeter of the single tunnel.

Finally, Femoral INTRAFIX offers the advantages of strong,stiff aperture fixation. With its unique patented screw andsheath design, Femoral INTRAFIX eliminates problems asso-ciated with graft rotation and damage as seen during theinsertion of interference screws. In addition, results from acadaveric comparative study show Femoral INTRAFIX pro-vides an average pullout strength of 800N vs. an interfer-ence screw average of 452N after a 1000 cycles loadedbetween 50 – 200N.*** Femoral INTRAFIX also experiencedan average displacement of less than 1mm compared to theinterference screw at approximately 3mm.***

Anatomic ACL ReconstructionUsing a Single Tunnel Through

an Anteromedial ApproachSurgical Technique by David Lintner, MD

Ordering Information

Femoral INTRAFIX IMPLANT SYSTEMS254680 Femoral INTRAFIX System 7-7.5mm Hard254681 Femoral INTRAFIX System 7-7.5mm Standard254682 Femoral INTRAFIX System 8-8.5mm Hard254683 Femoral INTRAFIX System 8-8.5mm Standard254684 Femoral INTRAFIX System 9-10mm Hard254685 Femoral INTRAFIX System 9-10mm Standard

Femoral INTRAFIX Instruments & Accessories254665 Femoral INTRAFIX Sheath Trial 7-7.5mm254666 Femoral INTRAFIX Sheath Trial 8-8.5mm254667 Femoral INTRAFIX Sheath Trial 9-10mm254668 Femoral INTRAFIX Sheath Inserter 7-7.5mm254669 Femoral INTRAFIX Sheath Inserter 8-8.5mm254670 Femoral INTRAFIX Sheath Inserter 9-10mm254671 Modular Hex Driver 21mm254672 Anteromedial Femoral Aimer 5.5mm254686 Anteromedial Femoral Aimer 6.5mm254687 Anteromedial Femoral Aimer 7.5mm254677 Femoral INTRAFIX Graft Positioner254690 Graft Positioner Replacement Screw232024 Malleable Graft Retractor232300 ACL Disposable Kit

Femoral INTRAFIX Tray System215500 Femoral INTRAFIX ACL Fixation Tray215451 Large Sterilization Tray Lid

PRODUCT# DESCRIPTION

www.depuymitek.com | 1-800-382-4682© DePuy Mitek, Inc. 2009. All rights reserved. Printed in the USA.Dyneema® Purity is a registered trademark of Royal DSM N.V.P/N 901009. Rev. B 4/09

W I T H

900

800

700

600

500

400

300

200

100

0

Femoral INTRAFIX

Interference Screws

800 452

ACL TENSILE PULL-OUT (POST-CYCLING)

ACL GRAFT MIGRATION:FEMORAL INTRAFIX VS. INTERFERENCE SCREW

AV

ERA

GE

TEN

SILE

STR

ENG

TH(N

)

3.50

3.00

2.50

2.00

1.50

1.00

0.50

0.00

Femoral INTRAFIX

Interference Screws

0.99 2.96

MIG

RA

TIO

N(M

M)

FEMORAL INTRAFIX® VS. INTERFERENCESCREWS COMPARISON STUDYI. PREPARE GRAFTII.

A.A strength and stiffness comparison study wasconducted in cadaver knees to evaluate theeffects of cyclic loading on Hamstring ACLreconstruction. The results showed a significantimprovement in both strength and stiffness ofFemoral INTRAFIX vs. Interference Screws,reducing elongation from 3mm to 1mm andincreasing pullout from 452N to 800N with thetest knees cycled 1000 times under loading of 50Nto 200N at a frequency of 1/2 Hz.***

CREATE A TWO BUNDLE GRAFT (Figure 1a)

• For a semitendinosus gracilis autograft, foldthe graft in half over a single strand of #2ORTHOCORD® suture and mark 33mm from theproximal end. Create two bundles by whipstitching each side separately (#0 VICRYL® or #0ETHIBOND® is recommended) to 30mm from fold.

• For anterior/posterior tibialis allograft, fold thegraft in half over a single strand of #2 ORTHO-CORD suture and mark 33mm from the proxi-mal end. Tighten the independent fibers of theallograft by whip stitching each bundle sepa-rately onto itself (#0 VICRYL or #0 ETHIBONDrecommended) to 30mm from fold.

Note: Suturing the posterior edge of both strands to-

gether may help control bundle positioning during

screw placement. In addition, Suturing the proximal

bundles 2mm – 3mm past the entrance of the femoral

tunnel also helps to control bundle positioning during

screw placement.

Figure 1a

COMPLETED FEMORAL INTRAFIX ACL RECONSTRUCTIONIX.

A. FEMORAL INTRAFIX ACL RECONSTRUCTION WITHTIBIAL INTRAFIX (Figures 23a, 23b and 23c)

TIBIAL FIXATION

Figure 23a

Figure 23b

Figure 23c

Figure 25Figure 24

INTRAFIX Screw

INTRAFIXSheath

PL Bundle

AM Bundle

ACL footprint

Natural anatomicalACL footprint

B. Restoring the anatomic ACL footprint(Figures 24 and 25)

• Improved ACL Footprint Placement & Coverage*

• Controlled AM & PL bundle positioning

• Soft Tissue Interference Aperture Fixation

David Lintner, MD

Dr. Lintner is an Associate Clinical Professor in the Depart-ment of Orthopaedic Surgery at Weill Cornell College ofMedicine at the Methodist Hospital in Houston, Texas. He isalso the Head Team Physician and Medical Director for theHouston Astros Major League Baseball Team and Team Or-thopedist for the Houston Texans. Dr. Lintner has writtennumerous articles and continues to do research on newtechniques in knee and shoulder surgery. Dr. Lintner is amember of AOSSM, ISAKOS, and AAOS.

References

1. Darren A. Frank, M.D., Gregory T. Altman, M.D., and Paul Re, M.D. Hy-brid Anterior Cruciate Ligament Reconstruction: Introduction of a NewTechnique for Anatomic Anterior Cruciate Ligament Reconstruction.Arthroscopy: Vol 23, No 12 (December), 2007: pp 1354.e1-1354.e5

2. Mark E. Steiner, Martha M. Murray and Scott A. Rodeo, MD, Strategiesto Improve Anterior Cruciate Ligament Healing and Graft Placement.Am. J. Sports Med. 2008; 36; pp. 176 – 189

3. Harner CD, Baek GHB, Vogrin TM, Carlin GJ, Kashiwaguchi S, Woo SL.Quantitative analysis of human cruciate ligament insertions.Arthroscopy. 1999;15:741-749.

4. James F. Heming, DO, Jason Rand, PA-C, and Mark E. Steiner, MD.Anatomical Limitations of Transtibial Drilling in Anterior CruciateLigament Reconstruction Am. J. Sports Med. 2007; 35; pp.1708-1715

5. Loh JC, Fukuda Y, Tsuda E, Steadman RJ, Fu FH, Woo SLY. Kneestability and graft function following anterior cruciate ligamentreconstruction: comparison between 11 o’clock and 10 o’clock femoraltunnel placement. Arthroscopy. 2003;19:297-304.

6. Scopp J, Jasper L, Belkoff S, Moorman C. The effect of oblique femoraltunnel placement on rotational constraint of the knee reconstructedusing patellar tendon autografts. Arthroscopy. 2004;20:294-299.

7. Yagi M, Wong E, Kanamori A, Debski R, Fu F, Woo S. Biomechanicalanalysis of an anatomic anterior cruciate ligament reconstruction. AmJ Sports Med. 2002;30:660-666.

8. Yamamoto Y, Hsu WH, Woo S, Van Scyoc A, Takakura Y, Debski R. Kneestability and graft function after anterior cruciate ligament recon-struction: a comparison of a lateral and an anatomical femoral tunnelplacement. Am J Sports Med. 2004;32:1825-1832.

9. Yasuda K, Kondo E, Ichiyama H, et al. Anatomic reconstruction of theanteromedial and posterolateral bundles of the anterior cruciate liga-ment using hamstring tendon grafts. Arthroscopy. 2004;20:1015-1025.

10. John-Paul H. Rue, MD, LCDR, MC, USN, Neil Ghodadra, MD, andBernard R. Bach Jr, MD. Femoral Tunnel Placement in Single-BundleAnterior Cruciate Ligament Reconstruction: A Cadaveric Study RelatingTranstibial Lateralized Femoral Tunnel Position to the Anteromedialand Posterolateral Bundle Femoral Origins of the Anterior CruciateLigament. Am. J. Sports Med. 2008; 36; pp. 73-79

11. Fu FH, Bennett CH, Ma CB, Menetrey J, Lattermann C. Current trendsin anterior cruciate ligament reconstruction, part II: operative proce-dures and clinical correlations. Am J Sports Med. 2000;28(1):124-130.

12. Christopher D. Harner, M.D., Nicholas J. Honkamp, M.D., and Anil S.Ranawat, M.D.. Anteromedial Portal Technique for Creating the Ante-rior Cruciate Ligament Femoral Tunnel. Arthroscopy 2008;24:1 113-115

* Compared to existing techniques for single tunnel ACL reconstruction.

** Compared to existing transtibial techniques for single tunnel ACLreconstruction.

*** Data on File, DePuy Mitek, Inc. April, 2007. MILAGRO® InterferenceScrew was used in the testing to represent the family of all interferencescrews.

GRAFT PREPARATION

PREPARE GRAFT FOR DELIVERYIII.

B. USING THE GRAFT POSITIONING TOOL(Figure 4a & 4b)

• Alternatively, the Graft Positioning Tool can be usedto facilitate desired AM and PL positioning of the twobundle strands in the Femoral Tunnel during graftpassage. Note: When using the Graft Positioning Tool,it is recommended to upsize the tibial tunnel 1mmlarger than the graft to facilitate easy graft passageand rotation.

• With #2 ORTHOCORD looped through the graft, placethe graft in the fork on the positioning instrument,thus separating the graft into two bundles. (Figure 4a)

• Secure the graft sutures around the suture cleats onthe Graft Positioning Tool to maintain tension in bothbundle strands. (Figure 4b)

• Wrap graft in damp gauze and store for later steps.

A. USING A PROBE AND/ORMALLEABLE GRAFT RETRACTOR

• A probe (Figure 2) and/or DePuy Mitek MalleableGraft Retractor (Figure 3) can be used to control bundlerotation and positioning during graft insertion intothe femoral tunnel.

• Wrap graft in damp gauze and store for later steps.

B. MARK THE GRAFT

• Femoral graft side – Mark each strand at 30mm.Then, color a portion of the AM bundle andleave the PL bundle unmarked. (Figure 1b)

• Tibial graft side – whipstitch based on currenttechnique for desired fixation. It is recom-mended to use two different color sutures foreeasier identification of the AM and PL bundlesand to mark the AM bundle to match the mark-ing on the proximal side. (Figure 1c)

Figure 1b

Figure 4a

Figure 2 Figure 3

Figure 4b

Figure 1c

AM Bundle

PL Bundle

AM Bundle

PL Bundle

ANTEROMEDIAL (AM) PORTAL APPROACHFOR CREATING THE FEMORAL TUNNELIV.

A. CREATE FEMORAL AM PORTAL

• Standard arthroscopy portals are marked and incised.

• The “working” AM arthroscopy portal is placed 1cmmedial to the patellar tendon and just distal to theinferior pole of the patella (assuming no patellabaja).12 (Figure 5)

• The AM Portal can also be located while under directvisualization with the scope in the anterolateral por-tal by inserting a spinal needle just above the tibialplateau and anterior horn of the medial meniscus.

B. MARK FEMORAL TUNNEL LOCATION

• A small notchplasty is performed in most cases andthe over-the-top position is identified.

• Next, a 30˚ awl or spinal needle is placed through theAM portal with the knee at 90˚ of flexion. The awl orspinal needle is used to identify the ACL insertion siteon the femur and to mark the center of the proposedtunnel roughly 6mm to 8mm anterior to the poste-rior cortex at the 2-o’clock position for the left kneeor 10-o’clock position for a right knee.12 (Figure 6)

Figure 5

AM Portal

Figure 6

8mm

8.5mm

9mm

9.5mm

10mm

10.5mm

11mm

Tunnel

6.5mm

6.5mm

6.5mm

6.5mm

7.5mm

7.5mm

7.5mm

AM Femoral Aimer

2.5mm

2.25mm

2mm

1.75mm

2.5mm

2.25mm

2mm

Back Wall

ANTEROMEDIAL FEMORAL AIMER SIZING

Note: Posteriorization of fixated graft makes a thicker back wall more desirable.

CREATING THE ANTEROMEDIAL PORTAL

Figure 8a

C. PREPARE FEMORAL TUNNEL LOCATIONWITH AM FEMORAL AIMER(see femoral aimer sizing chart)

• With the knee at 90˚ of flexion, the DePuy Mitek AMFemoral Aimer is placed through the AM portal withthe tip placed posterior to the marked position forthe femoral tunnel. It is essential that the knee be at90˚ of flexion when marking the notch at the drillingsite to ensure correct femoral tunnel placement.(Figure 7a)

• The knee is then hyperflexed to 110˚ to 120˚ allowingaimer to move with the rotating condyle. Changingthe knee’s position by hyperflexing during drillingwill allow for a more anterior directed tunnel andavoids posterior wall blowout.12

• An Eyelet Drill Pin is placed through the AM FemoralAimer and advanced through the AM portal (Figure7b). The Drill Pin should exit the femur anterior to itsmidline (Figure 7c). Hyperflexion allows better accessto the medial portion of the lateral femoral condyleand the AM Femoral Aimers ensure approximately a2mm back wall to avoid compromising the posterioraspect of the tunnel. The Femoral Aimers are specif-ically contoured to fit the AM portal hyperflexiontechnique.

D. DRILL FEMORAL TUNNEL WITH ACORN REAMER

• An Acorn Reamer 1mm larger than graft size is passedover the guidewire and initially advanced by hand toatraumatically pass by the articular surface of themedial femoral condyle.12

• The femoral tunnel is drilled to a depth of 30mm. Insmall femurs, the femoral tunnel length may have tobe adjusted to avoid violation of the lateral femoralcortex. It is important to note that drill depths of lessthan 27mm may result in difficulties with trial andsheath insertion. (Figure 8a and 8b).

• A shaver is used to remove excess bone debris.

CREATING THE FEMORAL TUNNEL

Figure 7b

Figure 7a

Figure 8b

Figure 7c

Figure 11a

INTRODUCE GRAFTV.

A. TIBIAL TUNNEL PREPARATION

• Use the DePuy Mitek Tip to Tip or Elbow Aiming TibialGuide to drill the tibial tunnel.

Note: When using the Graft Positioning Tool, it is rec-ommended to upsize the tibial tunnel 1mm larger thanthe graft to facilitate easy graft passage and rotation.

B. CHOOSE GRAFT PASSING METHOD

• The Graft Positioning Tool or probe and/or DePuyMitek Malleable Graft Retractor can also be used forgraft passage to and facilitate graft positioning.

C. INTRODUCE GRAFT AND POSITIONIN FEMORAL TUNNEL

• Introduce the passing suture attached to a Drill Pinthrough the AM portal and Retrieve the passing suturethrough the tibial tunnel with a grasping instrument.(Figures 9a and 9b)

• Pass the two limbs of #2 ORTHOCORD® from the apexof the graft through the suture loop exiting the tibialtunnel. (Figure 10)

• With the knee at 110 to 120 of flexion, the graft su-tures are then shuttled through the knee via the su-ture loop and passed through the femoral tunnel andout the anterolateral thigh. Pull the graft sutures whileadvancing the Graft Positioning Tool through the tib-ial tunnel to the aperture of the femoral tunnel. Be-fore advancing the graft into the femoral tunnel, theAM and PL bundles are rotated to the desired position.(Figures 11a and 11b)

• Release the sutures from the Graft Positioning Tool byloosening both wheels when the graft is at the en-trance of the femoral tunnel. While maintaining theorientation of the Graft Positioning Tool, pull the graftinto the femoral tunnel using the fork on the instru-ment to guide the graft in. (Figure 12)

• Alternatively, in place of using theGraft Positioning Tool, a probeand/or Malleable Graft Retractorcan be used through the AMportal to position the AM and PLstrands into the desired locations.

INTRODUCE GRAFT

Figure 9a Figure 9b

Figure 11b

Figure 10

Figure 12

Figure 14

Figure 13

Figure 15

VI. TRIAL FEMORAL TUNNEL

A. INTRODUCE SHEATH TRIAL INTO FEMORAL TUNNEL

• Do not select and open implant size until the trial fit hasbeen determined.

• With the knee flexed at the same angle as when the femoraltunnel was drilled, introduce the Sheath Trial of a size equalto the size of the graft via the AM portal. (Figure 13)

• Place the keel of the Sheath Trial between the AM & PLstrands to create bundle separation. Rotate to obtain desiredpositioning before trial insertion (i.e. one strand posterior,the other inferior within the single tunnel). This can also befacilitated using a Malleable Graft Retractor. (Figure 14)

• Rotate the Sheath Trial to orient its broader convex surface(laser marked) to an anterior distal position in the femoraltunnel and manually insert trial tip between graft bundlesuntil snug. (Figure 14)

B. SELECT IMPLANT SIZE (see implant sizing chart)

• Femoral INTRAFIX® comes packaged in two implant systemscalled Hard (for hard bone) and Standard. The surgeonwill select the appropriate system based on assessment ofbone quality.

• Drive the Sheath Trial between graft and tunnel using amal-let until fully seated to the back shoulder of the trial. Thelaser mark on the inserter should not be visible when thetrial is completely inserted. In addition, it is very importantfor the shoulder of the trial to be flush or slightly recessedto create the dilation needed to properly insert the FemoralINTRAFIX Sheath Implant with the Sheath Inserter. (Figure15)

• The Sheath Trial should seat completely with moderateforce. If comfortable with trial fit, select Femoral INTRAFIXStandard System equal to trial size. If the bone is hard, usethe “Hard” system as indicated by the sizing guidelines(undersize the screw 1mm).

• If the Sheath Trial seats easily (i.e., without malleting)proceed with the next larger Sheath Trial size. If the largerSheath Trial completely seats, use the “Standard” sizingguideline.

• If the Sheath Trial cannot be fully seated, it is removed andthe system corresponding to the sizing guidelines for theprevious Sheath Trial is used.

• Remove the Sheath Trial from femoral tunnel (may requiremalleting) leaving the graft compressed posteriorly in thefemoral tunnel.

7 8

7.5 8.57-7.5

7-7.5 Hard 7mm Sheath, 6mm Screw

7mm Sheath, 7mm Screw7-7.5Standard

Graft Tunnel Trial System** System Includes

FEMORAL INTRAFIX SIZING GUIDELINES (MM)

Note: Screw size is ultimately the decision of the Surgeon. If the Trial is difficultto insert, use a smaller screw implant system that corresponds to the trial size.

INTRODUCE TRIAL

8 9

8.5 9.58-8.5

8-8.5 Hard 8mm Sheath, 7mm Screw

8mm Sheath, 8mm Screw8-8.5Standard

9 10

9.5 10.5 9-10

9-10 Hard 9mm Sheath, 8mm Screw

9mm Sheath, 9mm Screw9-10Standard

10 11 9mm Sheath, 9mm Screw9-10Standard

Screw Sheath

IMPLANTING THE FEMORAL INTRAFIX SYSTEMVII.

INTRODUCE SHEATH

Figure 16

A. IMPLANTING THEFEMORAL INTRAFIX SHEATH

• Once the Femoral INTRAFIX System size has beenselected, place the Femoral INTRAFIX Sheath onsame size Sheath Inserter shaft tip.

• With the knee flexed at the same angle as whenthe tunnel was drilled, insert the Sheath andSheath Inserter through the AM portal with thewide convex ribbed surface of the Sheath orientedanteriorly in the femoral tunnel. (Figure 16)

• Insert the Sheath between graft bundles until snug. (Figure 17)

• Drive Sheath between graft strands in the tunnel using a malletuntil fully seated to a depth of 2mm-3mm into the tunnel as indi-cated by the laser marking on the rear shoulder of the inserter. Thelaser mark on the inserter should not be visible when the Sheath iscompletely inserted. It is very important for the shoulder of theSheath Inserter to be flush or slightly recessed to prevent Sheathextrusion during Screw insertion. (Figure 18)

• Remove the Sheath Inserter (light malleting recommended) leavingthe Sheath in the femoral tunnel. If the Sheath backs out during in-strument removal, reinsert the inserter and mallet the Sheath backto the appropriate depth. Using light taps to disengage the SheathInserter from the Sheath will facilitate removal while maintainingSheath placement within the femoral tunnel. (Figure 19)

Figure 17 Figure 18 Figure 19

Figure 20

B. IMPLANTING THE FEMORAL INTRAFIX® SCREW

• Screw size is determined by the system chosen per thesizing guideline (in general, the Screw size is the same sizeas the Sheath size, unless the bone is hard, then it isundersized 1mm).

• With the knee flexed at the same angle, introduce theFemoral INTRAFIX Screw through the AM portal to the en-trance of the femoral tunnel. A Malleable Graft Retractorcan be used as a barrier between the graft and screw toprevent graft movement from the screw threads contact-ing graft fibers during insertion. (Figure 20)

• Drive the Screw into the Sheath and femoral tunnel until itis flush with the cortical surface and Remove the driver,leaving the Screw and Sheath in the femoral tunnel withthe graft fixated. (Figures 21a and 21b)

INTRODUCE SCREW

Figure 21a Figure 21b

AM AND PL BUNDLE POSITIONING FOR TIBIAL FIXATIONVIII.

AM & PL BUNDLE POSITIONING

A. AM & PL POSITIONING FOR TIBIAL FIXATION

• Introduce the Malleable Graft Retractor into the tibialtunnel between the AM and PL bundle. (Figure 22a)

• With the concavity of the Malleable Graft Retractorcupping the AM bundle, rotate the AM bundle so itsposition is anterior to the PL bundle. (Figure 22b)

• Remove the Malleable Graft Retractor leaving the AMand PL bundles in their desired positions and completethe ACL reconstruction with either DePuy Mitek’s TibialINTRAFIX® or MILAGRO® Interference Screw. (Figure 22c)

B. TIBIAL TUNNEL FIXATION

See INTRAFIX or MILAGRO Surgical Techniques forinstructions for use.

Figure 22a

Figure 22b Figure 22c

900

800

700

600

500

400

300

200

100

0

Femoral INTRAFIX

Interference Screws

800 452

ACL TENSILE PULL-OUT (POST-CYCLING)

ACL GRAFT MIGRATION:FEMORAL INTRAFIX VS. INTERFERENCE SCREW

AV

ERA

GE

TEN

SILE

STR

ENG

TH(N

)

3.50

3.00

2.50

2.00

1.50

1.00

0.50

0.00

Femoral INTRAFIX

Interference Screws

0.99 2.96

MIG

RA

TIO

N(M

M)

FEMORAL INTRAFIX® VS. INTERFERENCESCREWS COMPARISON STUDYI. PREPARE GRAFTII.

A.A strength and stiffness comparison study wasconducted in cadaver knees to evaluate theeffects of cyclic loading on Hamstring ACLreconstruction. The results showed a significantimprovement in both strength and stiffness ofFemoral INTRAFIX vs. Interference Screws,reducing elongation from 3mm to 1mm andincreasing pullout from 452N to 800N with thetest knees cycled 1000 times under loading of 50Nto 200N at a frequency of 1/2 Hz.***

CREATE A TWO BUNDLE GRAFT (Figure 1a)

• For a semitendinosus gracilis autograft, foldthe graft in half over a single strand of #2ORTHOCORD® suture and mark 33mm from theproximal end. Create two bundles by whipstitching each side separately (#0 VICRYL® or #0ETHIBOND® is recommended) to 30mm from fold.

• For anterior/posterior tibialis allograft, fold thegraft in half over a single strand of #2 ORTHO-CORD suture and mark 33mm from the proxi-mal end. Tighten the independent fibers of theallograft by whip stitching each bundle sepa-rately onto itself (#0 VICRYL or #0 ETHIBONDrecommended) to 30mm from fold.

Note: Suturing the posterior edge of both strands to-

gether may help control bundle positioning during

screw placement. In addition, Suturing the proximal

bundles 2mm – 3mm past the entrance of the femoral

tunnel also helps to control bundle positioning during

screw placement.

Figure 1a

COMPLETED FEMORAL INTRAFIX ACL RECONSTRUCTIONIX.

A. FEMORAL INTRAFIX ACL RECONSTRUCTION WITHTIBIAL INTRAFIX (Figures 23a, 23b and 23c)

TIBIAL FIXATION

Figure 23a

Figure 23b

Figure 23c

Figure 25Figure 24

INTRAFIX Screw

INTRAFIXSheath

PL Bundle

AM Bundle

ACL footprint

Natural anatomicalACL footprint

B. Restoring the anatomic ACL footprint(Figures 24 and 25)

• Improved ACL Footprint Placement & Coverage*

• Controlled AM & PL bundle positioning

• Soft Tissue Interference Aperture Fixation

David Lintner, MD

Dr. Lintner is an Associate Clinical Professor in the Depart-ment of Orthopaedic Surgery at Weill Cornell College ofMedicine at the Methodist Hospital in Houston, Texas. He isalso the Head Team Physician and Medical Director for theHouston Astros Major League Baseball Team and Team Or-thopedist for the Houston Texans. Dr. Lintner has writtennumerous articles and continues to do research on newtechniques in knee and shoulder surgery. Dr. Lintner is amember of AOSSM, ISAKOS, and AAOS.

References

1. Darren A. Frank, M.D., Gregory T. Altman, M.D., and Paul Re, M.D. Hy-brid Anterior Cruciate Ligament Reconstruction: Introduction of a NewTechnique for Anatomic Anterior Cruciate Ligament Reconstruction.Arthroscopy: Vol 23, No 12 (December), 2007: pp 1354.e1-1354.e5

2. Mark E. Steiner, Martha M. Murray and Scott A. Rodeo, MD, Strategiesto Improve Anterior Cruciate Ligament Healing and Graft Placement.Am. J. Sports Med. 2008; 36; pp. 176 – 189

3. Harner CD, Baek GHB, Vogrin TM, Carlin GJ, Kashiwaguchi S, Woo SL.Quantitative analysis of human cruciate ligament insertions.Arthroscopy. 1999;15:741-749.

4. James F. Heming, DO, Jason Rand, PA-C, and Mark E. Steiner, MD.Anatomical Limitations of Transtibial Drilling in Anterior CruciateLigament Reconstruction Am. J. Sports Med. 2007; 35; pp.1708-1715

5. Loh JC, Fukuda Y, Tsuda E, Steadman RJ, Fu FH, Woo SLY. Kneestability and graft function following anterior cruciate ligamentreconstruction: comparison between 11 o’clock and 10 o’clock femoraltunnel placement. Arthroscopy. 2003;19:297-304.

6. Scopp J, Jasper L, Belkoff S, Moorman C. The effect of oblique femoraltunnel placement on rotational constraint of the knee reconstructedusing patellar tendon autografts. Arthroscopy. 2004;20:294-299.

7. Yagi M, Wong E, Kanamori A, Debski R, Fu F, Woo S. Biomechanicalanalysis of an anatomic anterior cruciate ligament reconstruction. AmJ Sports Med. 2002;30:660-666.

8. Yamamoto Y, Hsu WH, Woo S, Van Scyoc A, Takakura Y, Debski R. Kneestability and graft function after anterior cruciate ligament recon-struction: a comparison of a lateral and an anatomical femoral tunnelplacement. Am J Sports Med. 2004;32:1825-1832.

9. Yasuda K, Kondo E, Ichiyama H, et al. Anatomic reconstruction of theanteromedial and posterolateral bundles of the anterior cruciate liga-ment using hamstring tendon grafts. Arthroscopy. 2004;20:1015-1025.

10. John-Paul H. Rue, MD, LCDR, MC, USN, Neil Ghodadra, MD, andBernard R. Bach Jr, MD. Femoral Tunnel Placement in Single-BundleAnterior Cruciate Ligament Reconstruction: A Cadaveric Study RelatingTranstibial Lateralized Femoral Tunnel Position to the Anteromedialand Posterolateral Bundle Femoral Origins of the Anterior CruciateLigament. Am. J. Sports Med. 2008; 36; pp. 73-79

11. Fu FH, Bennett CH, Ma CB, Menetrey J, Lattermann C. Current trendsin anterior cruciate ligament reconstruction, part II: operative proce-dures and clinical correlations. Am J Sports Med. 2000;28(1):124-130.

12. Christopher D. Harner, M.D., Nicholas J. Honkamp, M.D., and Anil S.Ranawat, M.D.. Anteromedial Portal Technique for Creating the Ante-rior Cruciate Ligament Femoral Tunnel. Arthroscopy 2008;24:1 113-115

* Compared to existing techniques for single tunnel ACL reconstruction.

** Compared to existing transtibial techniques for single tunnel ACLreconstruction.

*** Data on File, DePuy Mitek, Inc. April, 2007. MILAGRO® InterferenceScrew was used in the testing to represent the family of all interferencescrews.

RestoringAnatomic ACLFootprint

the

Improved ACL FootprintPlacement & Coverage*

By utilizing a patented sheath and screwdesign that spreads the graft around theperimeter of a single tunnel.

Controlled AM & PL BundlePositioning

Offers distinct bundle separation ina single tunnel.

Soft Tissue InterferenceAperture Fixation

Provides average pullout strength of804N with less than 1mm elongation.***

INTRODUCTION

The new Femoral INTRAFIX® ACL Fixation System fromDePuy Mitek, Inc. is designed to provide soft tissue femoralfixation for ACL reconstruction surgery using a single tunnelthrough an anteromedial approach with the use of eitherallograft or autograft. Femoral INTRAFIX, with its uniquepatented polypropylene sheath and PEEK screw implant de-sign offers a new technique to achieve a more anatomic ACLreconstruction with improved femoral footprint placementand coverage, controlled anteromedial (AM) and postero-lateral (PL) bundle positioning, and strong, stiff soft tissueaperture fixation*.

The current trend in ACL reconstruction techniques is tomore closely restore the anatomical footprint and kinemat-ics of the ACL through a more laterally (“lower”) positionedfemoral tunnel, which replaces portions of both the AM andPL bundles**.1,2,5,10,11 Femoral INTRAFIX achieves this re-sult using an anteromedial portal to accurately position asingle tunnel in the center of the femoral ACL footprint.Femoral INTRAFIX also creates an hourglass shaped foot-print by separating and controlling the positioning of thegraft strands toward the native location of the AM and PLbundles. The anteromedial approach allows flexibility inplacing the femoral tunnel independent of the tibial tunneland eliminates a preventable error of an excessively verticaltunnel position commonly seen with a transtibial ap-proach.1,4

It has been reported that kinematics of the reconstructedknee are strongly affected by the location of the tibial andfemoral tunnels. Biomechanical tests of cadaveric recon-structions demonstrate nearly normal knee kinematics whenthe tibial tunnel is close to the center of the tibial footprintand the femoral tunnel is placed in the center of thefemoral footprint.4-9 In addition, studies have reported thata lateralized tunnel placed lower in the notch and drilled inthe center of the ACL femoral footprint can effectively re-place approximately half of the AM bundle and PL bundlefootprints.10

To further address all the components of an anatomic ACLreconstruction, the shape of the footprint also needs to beevaluated. The native ACL footprint is not circular, and hastwo distinct regions for the AM and PL bundles. In contrastto other femoral fixation devices, Femoral INTRAFIX allowsthe strands of a soft tissue graft to be clustered into anhourglass configuration rather than a cylinder.2 Harner etal.3 reported insertional areas up to 3.5 times larger thanthe midsubstance of the ligament indicating that the colla-gen is spread around the perimeter of the insertion. Toachieve the goal of anatomic reconstruction, Femoral IN-TRAFIX fixates the AM and PL bundles in the shape of anhourglass, closely resembling the shape of the native ACLfootprint with the collagen segregated into two bundlesaround the perimeter of the single tunnel.

Finally, Femoral INTRAFIX offers the advantages of strong,stiff aperture fixation. With its unique patented screw andsheath design, Femoral INTRAFIX eliminates problems asso-ciated with graft rotation and damage as seen during theinsertion of interference screws. In addition, results from acadaveric comparative study show Femoral INTRAFIX pro-vides an average pullout strength of 800N vs. an interfer-ence screw average of 452N after a 1000 cycles loadedbetween 50 – 200N.*** Femoral INTRAFIX also experiencedan average displacement of less than 1mm compared to theinterference screw at approximately 3mm.***

Anatomic ACL ReconstructionUsing a Single Tunnel Through

an Anteromedial ApproachSurgical Technique by David Lintner, MD

Ordering Information

Femoral INTRAFIX IMPLANT SYSTEMS254680 Femoral INTRAFIX System 7-7.5mm Hard254681 Femoral INTRAFIX System 7-7.5mm Standard254682 Femoral INTRAFIX System 8-8.5mm Hard254683 Femoral INTRAFIX System 8-8.5mm Standard254684 Femoral INTRAFIX System 9-10mm Hard254685 Femoral INTRAFIX System 9-10mm Standard

Femoral INTRAFIX Instruments & Accessories254665 Femoral INTRAFIX Sheath Trial 7-7.5mm254666 Femoral INTRAFIX Sheath Trial 8-8.5mm254667 Femoral INTRAFIX Sheath Trial 9-10mm254668 Femoral INTRAFIX Sheath Inserter 7-7.5mm254669 Femoral INTRAFIX Sheath Inserter 8-8.5mm254670 Femoral INTRAFIX Sheath Inserter 9-10mm254671 Modular Hex Driver 21mm254672 Anteromedial Femoral Aimer 5.5mm254686 Anteromedial Femoral Aimer 6.5mm254687 Anteromedial Femoral Aimer 7.5mm254677 Femoral INTRAFIX Graft Positioner254690 Graft Positioner Replacement Screw232024 Malleable Graft Retractor232300 ACL Disposable Kit

Femoral INTRAFIX Tray System215500 Femoral INTRAFIX ACL Fixation Tray215451 Large Sterilization Tray Lid

PRODUCT# DESCRIPTION

www.depuymitek.com | 1-800-382-4682© DePuy Mitek, Inc. 2009. All rights reserved. Printed in the USA.Dyneema® Purity is a registered trademark of Royal DSM N.V.P/N 901009. Rev. B 4/09

W I T H

introduction restoring depuy mitek, inc. is designed to

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