revision tibia surgical technique...figure 14 figure 15 determining rotational alignment attach the...

REVISION TIBIA SURGICAL TECHNIQUE

1 | R E V IS I O N T I B I A S U R G I C A L T EC H N I Q U E

2 Indications & Contraindications

3 Surgical Technique At-a-Glance

5 Pre-operative Planning

6 Preparation of the Tibia

20 Assembling the Trials

23 Assembling the Implants

25 Component Implantation

TABLE OF CONTENTS

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Indications for UseThe APEX Knee™ System is intended for use as a primary or revision total knee replacement. This prosthesis may be used for the following conditions, as appropriate:

• Non-inflammatory degenerative joint disease, including osteoarthritis and avascular necrosis; • Rheumatoid arthritis; • Correction of functional deformity; • Revision procedures where other treatments or devices have failed

The porous coated femoral component may be used cemented or uncemented (biological fixation). The porous coated tibial baseplate component may be used uncemented (biological fixation). All other femoral, tibial baseplate, and patellar components are indicated for cemented use only.

The APEX Knee Modular System tibial augments are intended to be bolted to the tibia baseplate and cemented to the prepared tibia. The APEX Revision Knee System femoral augments are intended to be bolted to the femoral component and cemented to the prepared femur.

ContraindicationsAbsolute contraindications include: • Infection or sepsis or osteomyelitis; • Insufficient bone structure or quality which may affect the stability of the implant; • Rapid joint destruction or bone absorption; • Skeletal immaturity; • Muscular, ligamentous, neurological, vascular deficiencies or poor skin coverage, which may compromise the affected extremity; • Alcoholism or other addictions; • Sensitivity to the implant materials; • High levels of physical activity (e.g. competitive sports, heavy physical labor) • Obesity can produce loads on the prosthesis, which can lead to fixation failure or prosthesis breakage or fracture

Relative contraindications include: • Uncooperative patient or a patient with neurological disorders and incapable of following instruction; • Metabolic disorders which may impair bone formation or bone quality; • Distant foci of infection.

INDICATIONS & CONTRAINDICATIONS


4 5

9

* When using the IM tower, proceed to step 8

1 2 3

87

6

*

SURGICAL TECHNIQUE AT-A-GLANCE

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13

16

14

17

12

15

1110


Figure 2

Figure 1

Important ConsiderationsEnsure that the intramedullary guide tower included is used to make the cuts for both the augments and tray, when performing revision surgery.

It is important to note that the keeled tibia tray and stem are mated at a 90° angle.

PRE-OPERATIVE PLANNING

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Figure 4

Figure 3

Opening the Intramedullary CanalStart by putting the knee in maximum flexion and locating the center of the tibia after removing any prior implanted components and/or performing a “clean-up” cut.

Optional: Use a tibia template as a guide to find the entrance point to the intramedullary canal (fig. 3).

Center the drill and create an entry hole into the intramedullary canal using the starter drill (fig. 4).

PREPARATION OF THE TIBIA


Figure 6 Figure 7

Figure 5

Table 1

Modular/Cemented Fluted/Press-Fit StemsLength Options (mm) 100mm, 150mm 100mm, 150mm

Diameter 9-21mm (Odd Sizes Only)

*Size 21mm only comes in 0mm offset

10-24mm (Even Sizes Only)

Offset Options 0mm & 4mm

Reaming Diameter

Undersize Implant to Reamer by 1-3mm

Ex: If the last reamer used was 14mm, use a 13 or 11mm Modular

Cemented Stem

Line to Line with ImplantEx: If the last reamer used was 14mm,

use a 14mm Fluted Press-fit Stem

Reaming the Intramedullary CanalBegin reaming the intramedullary canal by using the 8mm starter reamer (fig. 5).

Markings on the reamer shaft indicate the depth of the reamer relative to the resected tibia (fig. 6).

Note: When using the keeled tibia baseplate, it is important to note that the effective length of the stem is increased by 16mm to accommodate the keel.

Once entry to the canal has been achieved, progressively ream the canal by starting with the 9 mm reamer, to appropriate depth, until the reamer is well stabilized in the canal and desired stem diameter is achieved.

Once proper fixation has been attained, leave the fixed reamer in place (fig. 7).


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Figure 8

Figure 9

Figure 11

Figure 10

Determining Stem SelectionPlace a tibial trial onto the proximal tibial surface and determine the size of the baseplate based on coverage (fig. 8).

With the tibia size determined, load the neutral stem adapter over the reamer shaft and onto the tibial tray trial (fig. 9). Once fully assembled, you should be able to determine if there is adequate coverage using a neutral stem.

If there is not adequate coverage, an offset stem must be used. If this is the case, remove the neutral adapter, and replace with the 4 mm offset adapter.

Offset coverage is adjusted by depressing the knob on the adapter while turning to a numerical (1-12) position. Releasing the knob will allow it to fix in place (fig. 10).

Note: Remember the offset needed as it will determine final implant selection. The numerical position is indicated from the line on the anterior face of the offset adapter (fig. 11).


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Figure 12

Figure 13

Assembling the Intramedullary TowerAssemble the IM tower as shown on fig. 12:

The adjustable tower adapter (short or long) passes through the adjustable tower and into the alignment guide.

The cut block slides up onto the tower and locks into place.

The assembly is properly in place (fig. 13).

Note: Care must be taken not to press the IM tower’s release button when attaching the cut block, as this may cause improper fixation to the IM tower.


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Figure 14

Figure 15

Determining Rotational AlignmentAttach the universal handle to the alignment tower, and insert into the corresponding holes on the tibia cut block (fig. 14).

Establish the appropriate rotation by referencing the first or second metatarsal, the medial third of the tibial tubercle, and/or the sulcus of the ankle (fig. 15).

Note: It is extremely important to set your rotation at this point. Once the augment cuts have been made, it is very difficult to adjust the rotation of the component.



Figure 16

Setting Resection LevelOnce the rotation of the components has been set, the resection height should be determined.

The angel wing can be inserted into the saw capture slot marked “P” to determine the amount of bone to be removed from the primary surface.

Resection is determined by the level of the tibial deficiency with the deficiencies compensated by interlocking augments.

Height of the cut block can be adjusted by turning the knob on the proximal end of the alignment tower. You will hear and feel a “click” for every additional millimeter to be resected.

The angel wing should be used to determine the number of augments needed to be below the level of the tibial defect.

Pinning the BlockThe tibial cut block is now pinned in place using Steinman pins.

Slide the cut block posteriorly until contact is made with the tibia.

The pins should be placed through the neutral pin holes, marked by the etched line, and tapped into place (fig. 16). Threaded Pins may also be used to secure the block.


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Figure 17

Figure 18

Tibial ResectionRemove the IM alignment tower from the reamer and cut block:

Depress the button on the face of the IM alignment tower while removing the IM alignment tower from both the reamer and the tibial cut block (fig. 17).

Remove the reamer from the canal.

Create the primary resection through the saw slots marked “P”. This resected surface will support the final implant (fig. 18).


C

BA


PREPARATION OF THE TIBIA: USING THE IM TOWER (OPTIONAL)

Locating the Tibial Intramedullary TowerPlace the IM alignment tower over the fixed reamer shaft, lowering it until contact is made with the resected tibia. If contact cannot be made due to the condition of the patient’s tibia, the base of the IM tower should be even with the remaining cortical bone. The tower can then be locked to the reamer shaft via the corresponding knob on the IM alignment tower.

The revision tibia cut block should now be connected to the IM tower. Slide the block onto the “T-rail” of the IM tower until it locks into place.

Note: Care must be taken not to press the IM tower’s release button when attaching the cut block, as this may cause improper fixation to the IM tower.

Determining Rotational AlignmentRotation of the component must be determined. Attach the universal handle (B) to the cut block, by way of the alignment tower (A), and dropping the alignment rod (C) through the universal handle.

Establish the appropriate rotation by referencing the first or second metatarsal, the tibial tubercle, and/or the sulcus of the ankle.

Note: It is extremely important to set your rotation at this point. Once the augment cuts have been made, it is very difficult to adjust the rotation of the component.

Additional Step

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PREPARATION OF THE TIBIA: USING THE IM TOWER (OPTIONAL) PREPARATION OF THE TIBIA: USING THE IM TOWER (OPTIONAL)

Adjustment of Tibial Resection HeightResection height can be determined by using the angel wing.

Height of the cut block can be adjusted by loosening the appropriate knob and sliding the block until the angel wing makes contact with the bone. The angel wing should also be used to determine the number of augments needed to be below the level of the tibial defect.

Pinning the BlockSlide the cut block posteriorly until contact is made with the tibia. Once position has been finalized, the locking knob should be tightened.

Pin the tibial cut block in place using Steinman pins.

The pins should be placed through the neutral pin holes, marked by the etched line, and tapped into place. Threaded pins may also be used to secure the block.

Additional Step



Figure 20 Figure 21

Figure 19

Tibial ResectionCreate the primary resection through the saw slots marked “P”.

Performing the Augment CutsThe vertical cut is made through the vertical saw cutting slot using a reciprocating saw.

Using the angel wing, determine the thickness of augments needed (fig. 19).

Each augment is 4 mm thick, with a maximum of 3 augments on each side.

Horizontal augment cuts are made through each medial/lateral slot location (fig. 20).

The cut block and pins can now be removed from the tibia (fig. 21).

Table 2

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Figure 23

Figure 22

Sizing the TibiaUsing a tibial tray trial and augment trials, determine the size of the proximal tibia, and the size of the augments to be used (fig. 23).

Use the tray trial that provides the best coverage without overhanging the tibial surface.

Tibial augments can be used either on the medial or lateral side and can be stacked in descending order to create a tapered wedge, to replicate the geometry of the tibia (fig. 22).

Assembling the Augment TrialAssemble the appropriate tibial baseplate trial and augment trial(s) using the augment bolt driver (fig. 23).

There are 3 different length bolts, depending on how many augments are used: 4 mm, 8 mm, and 12 mm.

Augment Selection with Keeled ComponentWhen using the keeled tibial component, augment compatibility is dependant on keel size.

Refer to Table 2 below to determine what size augments can be used, and in which order.


AUGMENT STACK ORDER

SIZE 1 TRAY

SIZE 2 TRAY

SIZE 3 TRAY

SIZE 4 TRAY

SIZE 5 TRAY

SIZE 6 TRAY

1 1 1, 2 1, 2, 3 1, 2, 3, 4 3, 4, 5 3, 4, 5, 6

2 1 1, 2 1, 2, 3 1, 2, 3, 4 3, 4, 5 3, 4, 5, 6

3 1 1, 2 1, 2, 3 1, 2, 3, 4 1, 2, 3, 4, 5

1, 2, 3, 4, 5, 6


Figure 26Figure 25Figure 24

Aligning the ComponentsInsert the reamer previously used for the tibial canal. Ensure appropriate diameter is achieved.

Load the tibial trial over the reamer and onto the tibial plateau.

Load the 4 mm offset or neutral adapter onto the reamer shaft and over the tibial tray trial (fig. 24).

If an offset stem is being used, be sure to have the adjustment knob dialed to previously determined offset, to set in the appropriate position (fig. 25).

Pin the trials into place using the headed Steinman pins.

The reamer and adapter can now be removed (fig. 26).


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Figure 27 Figure 28

Conical Reaming for a Keeled TibiaPlace the assembled tibial components onto the resected tibial surface and pin the components into place using headed Steinman pins.

The conical reamer guide can then be placed on the tibial tray trial (fig. 27). The conical reamer guide can be held in place by attaching a universal handle to the attachment feature on the anterior face of the trial.

With the conical reamer guide in place, drive the conical reamer into the tibia (fig. 28), and ream until appropriate depth is achieved.



Figure 29

Figure 31Figure 30

Tibial Keel PunchPrepare the bone bed for the tibia component’s keel using the tibial punch guide.

Attach the appropriate size tibial keel dart to the tibial punch guide by pressing the shaft’s button, and releasing once the dart is fixed in its position (fig. 29).

There are 3 tibial keels: 1 for each pair of sizes: 1/2, 3/4, and 5/6.

Punching the TibiaPrepare the bone bed by placing the tibial punch on the tibial tray trials (fig. 30).

Strike the impaction pad until the attachment of the tibial keel punch is even with the surface of the tibial tray (fig. 31).

Once the bone bed is prepared, retract the guide.



Figure 32

Assembling the Tibial TrialsUsing the predetermined sizing and offset, assemble the revision tibia trial components.

The augments are bolted into place with the augment trial bolts, and the augment bolt driver (fig. 32).

ASSEMBLING THE TRIALS

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Figure 33

Assembling the Stem TrialNext attach the stem pilot adapter. There are 2 adapters: neutral, and 4 mm offset.

Make sure the adapter is in the correct orientation, or the trials will not fit into the prepared tibia.

Note: The line indicating offset position is located posteriorly on the tibia baseplate component.

The adapter is then locked into place with the stem pilot coupler bolt and torque wrench.

Proceed to screw the appropriate length trial stem pilot onto the adapter.

The trial assembly can now be loaded onto the tibia (fig. 33).

Note: If assistance is needed removing the stem trial assembly, thread the modular tibia slap hammer adapter into the top of the pilot stem coupler bolt. Attach the slap hammer to the slap hammer adapter to remove the component from the tibia.



Figure 35

Figure 34

Assembling the Trial ComponentsPlace the assembled tibia trial components onto the resected tibial surface (fig. 34) and pin the components into place using headed Steinman pins.

Slide the tibia insert trials posteriorly into the joint space and perform range of motion trial (fig. 35).


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Figure 36

Assembling the Implant ComponentsAugments are assembled to the Revision tibia tray using the 4 mm, 8 mm, or 12 mm augment bolts; depending on how many augments are to be used (fig. 36).

The torque driver is used to finally secure the augment bolt and tibial peg in place.

The torque driver is turned clockwise until the line on the handle aligns with the first line of the shaft marked 60 in-lbs for the tibial peg, and aligns with the second line on the shaft marked 100 in-lbs for the augment bolt.

Proceed to load the stem onto the tibial tray, ensuring that the offset alignment markings are aligned the same as trialing (fig. 37).

ASSEMBLING THE IMPLANTS

Figure 37

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Figure 38

Assembling the Implant ComponentsOnce the augments have been fixed into place, the stem can be assembled to the tray.

Using the stem impactor, with the tibia tray impactor pad, place the stem onto the tray with light force. Once the stem has been partially fixed to the tray, the tibial tray inserter should be used to press the implants together.

Using downward force while turning the handle clockwise, thread the spring loaded inserter handle into the tray.

Once fully tightened, the Inserter can then be used to place the assembled implant into its final position (fig. 38).

Note: It may be advisable to assemble the morse taper on the back table. Protecting the implants’ proximal and distal surfaces is important to retain the integrity of the implant.

ASSEMBLING THE IMPLANTS


Figure 39

Placing the ImplantsThe tibial tray can then be placed and impacted using the tibial tray inserter, with the revision tibia tray impactor pad.

Once the tibial tray has been impacted into place, the inserter can be removed by turning the handle counter clockwise (fig. 39).

COMPONENT IMPLANTATION

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Figure 40

Cement CompressionImmediately upon putting the tibial component in place, the desired thickness tibial insert trial is placed on the tibial tray. The knee should then be brought into maximal extension and held into position as the cement cures.

Any additional cement that is extruded during cement compression should be removed at this time.

Once the cement has cured, the knee is brought back into flexion, and the tibial trial can be removed using the tibial trial forceps (fig. 40).



Figure 41

Table 3

Placing Tibial InsertAll extraneous cement must be removed from the borders of the tibial tray. The surface of the tibial tray should be meticulously cleaned prior to placement of the tibial insert.

A tibial insert that matches the numerical size of the femoral component should be inserted onto the tibial tray in the anterior to posterior direction (fig. 41). The rails on the tibial tray engage the grooves on the bottom of the tibial insert.

Inserting Locking BoltThe revision tibia insert locking bolt may be inserted as this time. For PS, PS-C, and PS-R Inserts, the locking bolts correspond to the insert thickness. The chart below indicates what bolt with insert size.

Note: The bolts range in size. For example: the 10mm bolt can be used with 10mm and 11 mm insert. Please see table 3.

If the locking bolt does not thread easily into the hole, first check that the tibia Insert has been completely pushed posteriorly onto the tibia tray. Also check for debris that may be obstructing insertion of the bolt.

pRODUCT CODE DESCRIpTION

KP-21110 Retaining Bolt, PS or PS-C Insert, Revision Tibia Baseplate, 10-11mm

KP-21112 Retaining Bolt, PS or PS-C Insert, Revision Tibia Baseplate, 12-14 mm

KP-21116 Retaining Bolt, PS or PS-C Insert, Revision Tibia Baseplate, 16-18 mm

KP-21120 Retaining Bolt, PS- or PS-C Insert, Revision Tibia Baseplate, 20 mm

KP-39110 Retaining Bolt, PS-R Insert, Revision Tibia Baseplate, 10-11mm

KP-39112 Retaining Bolt, PS-R Insert, Revision Tibia Baseplate, 12-14 mm

KP-39116 Retaining Bolt, PS-R Insert, Revision Tibia Baseplate, 16 -18mm

KP-39120 Retaining Bolt, PS-R Insert, Revision Tibia Baseplate, 20 mm



KC-53002 Retaining Bolt, Congruent or Ultra Insert, Revision Tibia Baseplate


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Figure 42

Figure 43

Tightening Locking BoltOnce the cement has fully cured, final locking of the bolt is performed. With the knee in full flexion, the torque driver is used to achieve final tightening of the bolt (fig. 42).

Note: The torque driver must be turned until the lines are aligned at the 60 in/lb marking (fig. 43).


OMNIlife science, Inc.480 Paramount DriveRaynham, MA 027671-508-824-2444www.omnils.com KL-028 REV 4/18

revision tibia surgical technique...figure 14 figure 15 determining rotational alignment attach the...

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