Surgical Technique

REFLECTION™ Cemented All Polyethylene /All Polyethylene XLPE Acetabular Components

ContentsDesign Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Surgical Technique/Preoperative Planning. . . . . . . . . . . . . . . . . . . 7

Acetabular Exposure and Reaming . . . . . . . . . . . . . . . . . . . . . . . . 7

Acetabular Preparation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Cement Compression. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Acetabular Cup Insertion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Catalog Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Nota Bene

This technique description herein is made available to the healthcare professional to illustrate theauthors' suggested treatment for the uncomplicated procedure. In the final analysis, the preferredtreatment is that which addresses the needs of the patient.

designed in conjunction withRamon B. Gustilo, M.D.Richard F. Kyle, M.D.Hennepin County Medical CenterMinneapolis, Minnesota

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Design Features

The Reflection Cemented AcetabularComponent uses design features providedto maximize stability and durability incemented acetabular cups.

The outer surface of the cup is designedto improve the bond strength of the PE-cement-bone interface. The cup exterior isridged in the radial direction and groovedin the polar direction. This designincorporates cement-thickness equalizingpods and a continuous flange that providesa uniform thickness of cement around thecup to even the load transfer to the cementand bone. With the extended flange,eccentric cup placement is prevented.The flange also increases cement intrusionpressure and penetration into cancellousbone during cup insertion. The polargrooves increase torque resistance bycreating an interlock between the cementand cup. The grooves, ridges, and cementequalizing pods have been designed toreduce the risk of cup loosening. A wiremarker along the cup equator is a referencefor radiographic cup orientation andwear measurement.

The Reflection Cemented All PolyethyleneAcetabular Component is available in3 mm outer diameter increments with innerdiameters of 22, 28, and 32 mm. TheReflection Cemented All Polyethylene XLPEAcetabular Component is also available in 3mm outer diameter increments with innerdiametersof 22, 28, 32, and 36 mm.

The Reflection All PolyethyleneAcetabular cup is sterilized by anondegrading method to eliminatedamage associated with gammasterilization.

Grooves

Wire marker

Pressurizing flange

PMMA pods

Ridges

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Outer diameter sizes:40 mm to 64 mm in3 mm increments

20° Overhang design

Inner diameter sizes:All Poly: 22, 28, & 32 mmAll Poly XLPE: 22, 28, 32, & 36 mm

The articulating surface of the polyethylenecup has distinctive design features forstability of the hip joint. Because the naturalabduction angle of the acetabulum is about60º, the positioned cup is usually precipitouswhich can cause superoposterior dislocationof the femoral head component. In orderto prevent dislocation, the cup has to bepositioned at a more horizontal angle andthe cup will be exposed outside of the bonyacetabulum, particularly superoposteriorly.To avoid these problems, the articulatingsurface of the polyethylene cup is angled20º toward the horizontal plane. This providesmore coverage on the superoposterior aspectwhile keeping the center of hip rotation thesame as the geometric center of the outershell. The resulting abduction face angleof the polyethylene cup is a stable 40º(See Figure 1 on page 4).

Design Features

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Design Features

The Reflection cup does not lateralizethe center of the natural acetabulum, animportant design feature for reconstructionof hip geometry (Figure 1). Somecompetitive designs can lateralize thenatural center of the joint (see Figure 2).When the center of hip rotation islateralized, the body weight moment armis increased and the abductor momentarm is relatively decreased. Thus, jointforce is increased and the resultant jointforce direction is lateralized. This acts onthe overhang portion of the cup whichwill tend to rock the implant and causeplastic deformation and may lead toeventual early loosening of the implant(Figure 2).

In addition, the laterally protruded largeoverhang that other systems employmakes reduction of the femoral headextremely difficult during the reductionmaneuver. The Reflection All Polyethylenecup design minimizes these problems.

ReflectionAll PolyCup Design

All PolyCompetitiveCup Design

Figure 1

Figure 2

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Preoperative templating is essential tothe precise reconstruction of the hip joint.Suggested preoperative X-rays include an A-P of the pelvis and hips, a 14" x 17" A-Pview of the affected hip and femur, and alateral view of the affected hip.

The acetabular component may betemplated using the contralateral normalhip, if available, or templated directly onthe affected hip. The acetabularcomponent and cement pods shouldcongruently fit the subchondral boneand the medial aspect of the acetabulum,as indicated by the teardrop. Mark thecenter of rotation of the acetabularcomponent through the template forsubsequent reference.

Complete exposure of the acetabulum isnecessary to ensure a satisfactory surgicalresult. Resect the acetabular labrumcircumferentially in order to define thelandmarks of the bony acetabulum. Cleanthe soft tissue of osteophytes from theacetabular fovea in order to define thelimits of the medial wall. Retractsurrounding soft tissues to protect themduring the reaming process. This will helpavoid injury to critical structures.

To expose the acetabular rim, first place adouble angled, sharp Hohman retractor inthe 3 o'clock position (for the right hip)over the anterior acetabular rim, takingcare to maintain the top of the retractoragainst the anterior aspect of the pelvis.

Surgical Technique/Preoperative Planning

Acetabular Exposure and Reaming

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Acetabular Exposure and Reaming continued

Place an inferior retractor in approximatelythe 7 o'clock position adjacent to theischium. If desired, place a sharp, straightHohman retractor in the 12 o'clock positionbeneath the abductors, approximately 2.5cm above the superior rim of theacetabulum, and impact into the boneto enhance retraction of the abductors.

Restoration of natural anatomy is thegeneral goal of acetabular preparation.The acetabulum is medialized to restorethe normal center of hip rotation.Additionally, remaining cartilage andweak osteophytes are removed to preparebone surface for cement interdigitation.

After performing the femoral osteotomy,an initial sizing of the acetabulum can beperformed by using the trial shells andtrial handle (Figure 3).

Using the existing anatomy as the reamerguide, ream the acetabulum concentrically,starting with a reamer two sizes smallerthan the estimated final size. Proceedwith reaming to expand the acetabulumuntil bleeding subchondral bone isreached (Figure 4).

The outer diameter of the last reamerused should be equal to the size of thecup to be implanted. A final confirmationof acetabular size can be made afterreaming by using the trial shell andtrial handle.

Figure3

Figure 4

Trial Shell Handle

Cat. No. 7136-2297

Reamer Handle

Cat. No. 7136-2279

Reamer Dome

Cat. No. 7136-2742

Trial Shell

Cat. No. 7136-2345

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Acetabular CementCompressor

Cat. No. 11-1430

Multiple small anchoring holes in thepubic, ischial, and iliac portions of theacetabulum will provide greater fixationand torsional resistance for the cementmantle. Use an angled, depth-controlleddrill, taking care not to penetrate into thepelvis (Figure 5).

Irrigate the acetabulum with antibioticsolution. Remove bone and blood debriswith an acetabular brush connected toa power drill.

To achieve good cement intrusioninto cancellous bone and anchor holes,the acetabulum must be clean and dry.Pack gauze into the socket until cement isready to be introduced.

Remove gauze and introducecement as a bolus. Using acement compressor larger thanthan the acetabular mouth, applysustained, firm pressure for 15seconds (Figure 6).

Remove extruded cement from theperiphery of the compressor and twistcompressor end out of cement. Any bloodoozing onto the surface of the cementshould be dried with a sponge beforeinserting the acetabular component.

Acetabular Preparation

Cement Compression

Figure 5

Figure 6

Acetabular CementCompressor Cap

Cat. No. 11-1431

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Acetabular Cup Insertion

Select an acetabular component equal insize to the last reamer used.

Position the cup onto the Positioner/Placement Head. Orient the Positioner/Placement Head to indicate left or rightTHA. Engage the two pins on theplacement head into the correspondingholes of the cup to firmly hold it in place(Figure 7).

Vertical orientation of the X-bar and align-ment of the appropriate cross bar with thebody axis provides 45º of abduction and20º of anteversion.

Insert the cup into the cement andfully seat, positioning the overhang inthe posterosuperior position to providegreatest stability (Figure 8). The PMMAspacer pods provide a uniform 2.5 mmcement mantle. Trim away excesscement from the periphery of the cuponce it has become doughy.

Disengage the cup by pushingthe button on the cup positioner.

Cover the acetabular area with asponge while preparing the femurand inserting the femoral prosthesis.

Figure 7

Positioner

Cat. No. MT-2200

Placement Head

Cat. No. MT-2222

X-Bar

Cat. No. MT-2201

Figure 8

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REFLECTION™ Cup Catalog NumbersAll Poly All Poly XLPE O.D. I.D.7135-2240 7135-8001 40 mm 22 mm7135-2243 7135-8002 43 mm 22 mm7135-2246 7135-8003 46 mm 22 mm7135-2249 7135-8004 49 mm 22 mm7135-2252 7135-8005 52 mm 22 mm7135-2255 7135-8006 55 mm 22 mm7135-2258 7135-8007 58 mm 22 mm7135-2261 7135-8008 61 mm 22 mm

7135-2846 7135-8023 46 mm 28 mm7135-2849 7135-8024 49 mm 28 mm7135-2852 7135-8025 52 mm 28 mm7135-2855 7135-8026 55 mm 28 mm7135-2858 7135-8027 58 mm 28 mm7135-2861 7135-8028 61 mm 28 mmN/A 7135-8029 64 mm 28 mm

7135-3249 7135-8034 49 mm 32 mm7135-3252 7135-8035 52 mm 32 mm7135-3255 7135-8036 55 mm 32 mm7135-3258 7135-8037 58 mm 32 mm7135-3261 7135-8038 61 mm 32 mmN/A 7135-8039 64 mm 32 mm

N/A 7135-8065 52 mm 36 mmN/A 7135-8066 55 mm 36 mmN/A 7135-8067 58 mm 36 mmN/A 7135-8068 61 mm 36 mmN/A 7135-8069 64 mm 36 mm

REFLECTION Trial ShellCat. No. Size7136-2340 40 mm7136-2341 41 mm7136-2342 42 mm7136-2343 43 mm7136-2344 44 mm7136-2345 45 mm7136-2346 46 mm7136-2347 47 mm7136-2348 48 mm7136-2349 49 mm7136-2350 50 mm7136-2351 51 mm7136-2352 52 mm7136-2353 53 mm7136-2354 54 mm7136-2355 55 mm7136-2356 56 mm7136-2357 57 mm7136-2358 58 mm7136-2359 59 mm7136-2360 60 mm7136-2361 61 mm7136-2362 62 mm7136-2363 63 mm7136-2364 64 mm

Catalog Information

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Catalog Information

REFLECTION™ Trial Shell HandleCat. No. 7136-2297

REFLECTION Reamer DomesCat. No. Size7136-2738 38 mm7136-2739 39 mm7136-2740 40 mm7136-2741 41 mm7136-2742 42 mm7136-2743 43 mm7136-2744 44 mm7136-2745 45 mm7136-2746 46 mm7136-2747 47 mm7136-2748 48 mm7136-2749 49 mm7136-2750 50 mm7136-2751 51 mm7136-2752 52 mm7136-2753 53 mm7136-2754 54 mm7136-2755 55 mm7136-2756 56 mm7136-2757 57 mm7136-2758 58 mm7136-2759 59 mm7136-2760 60 mm7136-2761 61 mm7136-2762 62 mm7136-2763 63 mm7136-2764 64 mm

REFLECTION Reamer HandleCat. No. 7136-2279

REFLECTION Ratchet HandleCat. No. 7136-2294

Power AdaptersCat. No. Description7136-2781 Synthes7136-2782 Aesculap7136-2783 Hudson

PositionerCat. No. MT-2200

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X-BarCat. No. MT-2201

Placement Heads Cat. No. SizeMT-2222 22 mmMT-2228 28 mmMT-2232 32 mm7136-7436 36 mm

Acetabular Brush6 per boxCat. No. 11-0032

Concise Cement Sculps KitCat. No. 11-1000

Disposable Acetabular CementCompressor Cap with Shield5 per boxCat. No. Size11-1431 Small, 54 mm dia.11-1432 Medium, 62 mm dia.11-1433 Large, 70 mm dia.

Acetabular Cement Compressor6 per boxCat. No. 11-1430

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REFLECTION All PolyInstrument TrayCat. No. 7136-7006

REFLECTION™ Trial Shell TrayCat. No. 7136-2282

REFLECTION Primary Reamer TrayCat. No. 7136-2281

REFLECTION Small Reamer/Trial TrayCat. No. 7136-2286

Catalog Information

OrthopaedicsSmith & Nephew, Inc.1450 Brooks RoadMemphis, TN 38116USA

Telephone: 1-901-396-2121Information: 1-800-821-5700Orders/Inquiries: 1-800-238-7538

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