LCS COMPLETE SURGICAL TECHNIQUE. MILESTONE Instruments with MBT Tray Preparation

Transcription

1 LCS COMPLETE MILESTONE Instruments with MBT Tray Preparation SURGICAL TECHNIQUE

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3 CONTENTS Preface 2 Surgical Concepts 3 Instruments 4 Surgical Technique Summary 6 Surgical Technique 8 Preparation 8 Incision and Exposure 8 Ligament Balancing 9 Tibial Resection 10 Femoral Sizing 14 Femoral Preparation 15 Femoral Rotation Determination & Flexion Balancing 16 A/P Femoral Resection 18 Distal Femoral Resection 19 Femoral Finishing Resection 22 Tibial Plateau Preparation 23 Central Stem Preparation 23 MBT Tray Preparation 25 MBT Keel Tray Preparation 25 Trial Reduction 26 Tibial Bearing Selection 28 Patellar Resection 29 Patellar Trial 30 Non-Cemented Implantation 32 Cemented Implantation 35 Ordering Information 39 Surgical Technique LCS COMPLETE DePuy Synthes Joint Reconstruction

4 PREFACE Any new concept that is introduced usually goes through a series of evolutionary changes as it is perfected. Each change hopefully improves the original concept. The LCS Total Knee System was first implanted by the designer in The system was subjected to a rigorous FDA approved multicenter clinical investigation to prove its safety and efficacy. 1 It became nationally available in the United States in The instruments that were initially used reflected a very conservative surgical approach. The objective was to ensure that a precise and reproducible surgical procedure could be performed and that equal flexion and extension gaps could be achieved in the process. Since 1985, total knee arthroplasty (TKA) instrumentation has evolved significantly. As technique improvements have been made, they have been evaluated and modifications made to the initial instrumentation. The first major modification, the API (Advanced Performance Instrumentation), proved to be a significant improvement and is currently in worldwide usage. 2 This surgical technique has been developed to provide the surgeon with a clear explanation describing the use of the MILESTONE Instruments. The technique has gone through an evolutionary process with input from a number of surgeons and engineers. Shortcuts and technique tips have been identified through the 24 years of usage and many are included in the following technique. I am grateful to Louis Jordan, MD, for his help in defining the patellar portion of the technique and to Peter A. Keblish, MD, for his review of the interim manuscript and for his suggestions. I am also grateful to Frederick F. Buechel, MD, and Michael J. Pappas, PhD, who started it all. R. Barry Sorrells, MD Author of the MILESTONE Surgical Technique The MILESTONE Instruments reflect the state of the art in total knee arthroplasty. The transmalleolar axis and palpable bony landmarks are used to reliably orient the tibial cut. Preset angles and dimensions are used where possible. The isthmus of the femoral canal is referenced to help define the distal femoral valgus correction angle, and the femoral finishing cuts are made through one instrument. 2 DePuy Synthes Joint Reconstruction LCS COMPLETE Surgical Technique

5 SURGICAL CONCEPTS Total knee arthroplasty represents a major advance in the management of severe, crippling arthritis. Success of the procedure is dependent on the skills of the surgeon and the surgical team, coupled with the design of the implant and instrumentation. A scientifically sound design must be complemented by easily used instruments and a technique that assures accuracy and reproducibility. The surgical procedure to follow provides the surgeon with the necessary information to achieve accurate and reproducible results using the LCS Total Knee System with the MILESTONE Instruments. The technique incorporates the basic surgical philosophies of balanced flexion and extension gaps developed by Michael Freeman, FRCS, and John Insall, MD. In the normal knee, the majority of rotation occurs laterally with less motion seen medially; both condyles pivot about the intercondylar eminence as the center of rotation. This surgical technique is based on the principle that reproducing normal knee rotation is desirable when the anterior and/or posterior cruciate ligaments are sacrificed. If the posterior cruciate is absent or substituted, the axis of rotation remains central and equally shared by both compartments. The design of the implant allows for this and eliminates the need for right and left tibial components or bearings. In this technique, the objective is to produce a knee that has equal soft tissue tension medially and laterally in both flexion and extension. This results in a stable total knee throughout the range of active and passive motion. Such stability maintains contact pressure on the mobile bearings and protects against subluxations and dislocations. Femoral component sizing is chosen to approximate the original A/P and M/L anatomy. A tibial-cut-first approach is used to provide a logical, time-tested method that first establishes the flexion gap, and then an extension gap to match. Since the sagittal tibial cut is non-variable, subsequent femoral cuts are referenced from the resected tibia. The proximal tibia is cut with a posterior inclination parallel to the patient s anatomic inclination angle. This provides better flexion, creates compressive loading of the tibial components and avoids shearing effects associated with perpendicular plane resections. Primary femoral bone cuts preserve a maximum of bone stock using the anterior femoral cortex and the isthmus of the femoral canal for surgical reference. Slight external rotation of the femoral component results from referencing the resected proximal tibia. This allows the femoral resections to parallel the proximal tibia with the collateral ligaments tensioned. This also provides a stable tracking position for the patella that helps avoid subluxation. A measured resection of the patellar articular surface, usually at the level of the quadriceps and patellar tendon insertion, allows sufficient bone stock and blood supply to implant a 3-peg fixturing element. This stabilizes a rotating bearing or all polyethylene fixed patellar replacement. Surgical Technique LCS COMPLETE DePuy Synthes Joint Reconstruction 3

6 MILESTONE, MBT INSTRUMENTS Tibial Instruments Tibial Resection Guide SP2 Tibial Tray Alignment Handle Ankle Clamp SP2 Universal Handle Tibial Resection Block Varus/Valgus Tibial Resection Block Tibial Stylus MBT Tray Trial MBT Keel Punch MBT Keel Punch Extractor MBT Keel Punch Bushing MBT Central Drill MBT Stem Punch MBT Drill Bushing MBT RP Plateau Trial Post MBT Tray Impactor MBT Tray Trial Fixation Pins MBT Punch Bushing Femoral Instruments Anterior/Posterior Cutting Block Guide Yoke Initiator Drill (9 mm) I.M. Rod (9 mm) Femoral Guide Positioner I.M. Rod (40 cm) Distal Cutting Guide Distal Femoral Cutting Block Femoral Finishing Guide Femoral Extractor Femoral Sizing Template Femoral Impactor Modular Depth Stop Ring 4 DePuy Synthes Joint Reconstruction LCS COMPLETE Surgical Technique

7 Patellar Instruments General Instruments Caliper Spacer Block Modular Clamp Femoral Spacer Adapter Modular Face Plate Tibial Spacer Adapter Modular Clamp Head Lug/Peg Drill Patellar Resection Guide LCS Patellar Reference Arm 3-Peg Patellar Templates, Modular 3-Peg Patellar Templates, Thin General Instruments Saw Capture Alignment Tower and Rod Slap Hammer Flatness Gauge Pin Extractor Pin Holder Alignment Rod Surgical Technique LCS COMPLETE DePuy Synthes Joint Reconstruction 5

8 SURGICAL TECHNIQUE SUMMARY 1. Resect proximal tibia and balance soft tissues in extension. 2. Size femur, position A/P block and drill intramedullary guide hole. 6. Check extension gap. 7. Finish femoral resections. 6 DePuy Synthes Joint Reconstruction LCS COMPLETE Surgical Technique

9 3. Set femoral rotation; resect A/P femoral condyles. 4. Check flexion gap. 5. Resect distal femur Finish tibia. 9. Measure, resect, orient and drill the patella. Surgical Technique LCS COMPLETE DePuy Synthes Joint Reconstruction 7

10 PREPARATION, INCISION AND EXPOSURE Anatomic Axis Mechanical Axis Valgus Angle Alternate skin incision for varus exposure (figure 1) (figure 2) Skin Incision (figure 3) Neutral or Fixed Varus Knee (figure 4) Valgus Knee Pre-operatively, obtain a standing A/P x-ray of both the femur and tibia centered on the knee joint. On the x-ray, draw a line through the center of each femoral canal to the center of the knee joint (anatomic axis). Draw a line through the center of each femoral head to the center of the knee joint (mechanical axis). The angle between these two lines is the valgus angle (Figure 1). Measure the valgus angle of both knees. The normal angle varies from 3 to 8 degrees and should be individualized for each patient in the distal femoral resection. Draw a transverse tibial line perpendicular to the I.M. line at the level of the anticipated resection. It is recommended by the author that the following valgus angles be used based on the patient s height: Height < 5 11 Height Height > degrees 4 degrees 3 degrees Pre-operatively assess component sizing and resection depths in both the A/P and M/L planes using the x-ray templates. With the knee slightly flexed, make a straight midline incision from 3 to 4 in. above the patella, over the patella, and ending at the tibial tubercle (Figure 2). With neutral alignment or with varus deformity, make a median parapatellar incision through the retinaculum, capsule and synovium (Figure 3). The subvastus approach may be used. If significant valgus deformity exists, a lateral parapatellar deep incision as part of a lateral release may be preferred (Figure 4). 3, 4 8 DePuy Synthes Joint Reconstruction LCS COMPLETE Surgical Technique

11 LIGAMENT BALANCING LCL and PT elevated with periosteal attachment ITB elevated subperiosteally MCL and pes anserinus elevated subperiosteally (figure 5) (figure 6) Valgus Knee Releases (figure 7) Varus Knee Releases Following a median parapatellar incision, reflect the patella laterally to expose the entire tibiofemoral joint (Figure 5). Should tension prevent adequate lateral displacement of the patella, detach the medial one-fourth to one-third of the patellar tendon from the tibial tubercle. To further mobilize the extensor mechanism, continue the sharp incision of the medial portion of the quadriceps tendon proximally. Following a lateral parapatellar incision in the valgus knee, incise the anterior compartment fascia longitudinally 1 cm from the tibial tubercle. Elevate the tibial tubercle with an osteo-periosteal flap if necessary for patellar reflexion. Reflect the patella and periosteal attachments medially. 3, 4 Excise hypertrophic synovium and a portion of the infrapatellar fat pad to allow access to the medial, lateral and intercondylar spaces. Excise redundant synovium to prevent possible impingement or postoperative overgrowth. Some surgeons prefer a complete synovectomy. For better exposure, a preliminary patellar resection may be performed at this stage. (see Patellar Resection on page 29) By reducing patellar bulk, eversion may not be necessary. The patellar remnant can simply be displaced to the side, lessening tension on its tubercle insertion. Remove femoral and tibial osteophytes, especially any deep to the collateral ligaments. Lateral soft tissue release and, occasionally, osteotomy and removal of the fibular head (severe valgus) will enable correction of valgus contracture (Figure 6). Medial release will be necessary for a fixed varus deformity (Figure 7). An extensive medial tibial subperiosteal sleeve may be necessary in severe varus angulation. Surgical Technique LCS COMPLETE DePuy Synthes Joint Reconstruction 9

12 TIBIAL RESECTION Tibial cutting guide Tibial cutting block Ankle clamp (figure 8) (figure 9) (figure 10) After the proximal tibia and distal femur are cleared of soft tissue debris, sharply develop the soft tissue planes between the collateral ligaments and the joint surfaces. Expose approximately 1 in. of proximal tibia anteriorly, medially and laterally. Slide retractors deep to the collateral ligaments and anterior to the posterior capsule to protect the posterior neurovascular structures during resection of the tibial articular surface. An S or Z shaped retractor works well (Figure 5). Make a longitudinal mark from a point 6-8 mm medial to the midpoint between the prominence of the medial and lateral malleoli, extending to the second toe (Figure 8). Select the tibial cutting block (7 or 10 degrees) compatible with the posterior slope of the patient s tibia and attach it proximally to the tibial cutting guide. Attach the ankle clamp to the rod distally (Figure 9). Flex the knee to 90 degrees, position the tibia in about 10 degrees external rotation and clearly mark the center of the tibia with reference to the intercondylar notch of the femur (Figure 10). 11 DePuy Synthes Joint Reconstruction LCS COMPLETE Surgical Technique

13 (figure 11) (figure 12) (figure 13) (figure 14) Introduce the long spike of the alignment guide into the proximal tibial spines (Figure 11). Attach the ankle clamp by wrapping the spring around the ankle. Establish proper rotational alignment by positioning the appropriate malleoli wings parallel to the transmalleolar axis (Figure 12). Place the alignment rod proximally over the center mark on the tibia, usually slightly medial to the tibial tubercle. It should be directly over the longitudinal mark distally, just lateral to the tibialis anterior tendon (Figure 13). When the rod is parallel to the intramedullary axis of the tibia as viewed laterally, the posterior slope of the tibia should parallel the chosen resection block (7 or 10 degrees). The slope may be further adjusted by loosening the ankle clamp knob and sliding the rod anteriorly or posteriorly. When proper positioning is achieved, impale the second spike (Figure 14) and lock the ankle clamp knob. Surgical Technique LCS COMPLETE DePuy Synthes Joint Reconstruction 11

14 (figure 15) (figure 16) (figure 17A) Attach the stylus (0 or 2 mm) to the tibial cutting block on the side of the lower tibial compartment (Figure 15). Lower the cutting block and stylus by turning the knurled cylinder to the left until the tip of the stylus contacts the tibial plateau. Ensure that a minimum of 10 mm (total) of bone and cartilage is resected from the unaffected side of the tibia. Determine that the level of tibial resection is satisfactory, then predrill and place two 3 in. long fixation pins in the marked row of holes. Remove the stylus. (A 6 mm stylus is also provided. The 6 mm measurement is used when referencing the unaffected plateau.) Disconnect the spring from the ankle clamp and turn the knurled cylinder to the left until it drops free. Using a mallet or slap-hammer, gently remove the tibial cutting guide, taking care not to misalign the cutting block (Figure 16). Slide the cutting block flush to the tibia and further impact the two fixation pins. Check alignment by attaching the alignment tower and rod to the tibial cutting block. The distal end of the rod should lie over the longitudinal ankle mark, in line with the second toe and just lateral to the anterior tibialis tendon insertion (Figure 17A). If alignment is found to be in variance, the cutting block can be removed from the pins and 11 DePuy Synthes Joint Reconstruction LCS COMPLETE Surgical Technique 12

15 2 degree varus/valgus cutting block Standard tibial cutting block (figure 17B) (figure 18) (figure 19) the 2 degree varus/valgus block applied to the pins for correction (Figure 17B). Use corresponding holes. Since the fixation pin holes of all tibial cutting blocks are parallel to the cutting surface, this block will only alter the varus/valgus angle by 2 degrees and will not affect the posterior slope. Apply the saw capture and (Figure 18) resect the proximal tibia (Figure 19). With the RP insert, the PCL is generally sacrificed, but can be recessed based on surgeon preference. Remove the block. Leave the fixation pins in place. Once the proximal tibial bone has been removed, further ligament balancing becomes easier. With preexisting flexion contracture, preliminary removal of the tibial plateau usually allows full extension of the knee to facilitate ligament balancing. Before proceeding further, assure that the extremity can be brought into normal medial-lateral alignment in extension. Place traction on the foot or introduce medial and lateral spreaders to tension the collaterals, and perform additional soft tissue balancing until the normal mechanical axis is obtained. The electrocautery cord or suction tubing can be stretched from the center of the femoral head (approximately two finger breadths medial to the ASIS) to the center mark on the ankle. The line should pass through the center of the knee joint. This confirms that the ligaments are balanced in extension. Surgical Technique LCS COMPLETE DePuy Synthes Joint Reconstruction 11

16 FEMORAL SIZING Center Line Articular Cartilageˇ Lateral View (figure 20) (figure 21) Select a femoral sizing template. The inside of each template corresponds to the inside geometry of the selected size of femoral component. The outside of the template corresponds to the outside surface of the femoral component. When sizing, it is important to keep the anterior flange of the femoral component in the same plane as the anterior cortex. With the knee in flexion, place the femoral template against the lateral condyle to visually determine the best fit. Check to ensure the bony resection depths look reasonable (Figure 20). This will define the best A/P component fit and should be the primary sizing method. The M/L width of the femur can be measured at its maximal width with the knee flexed and can be used as a secondary reference for sizing (Figure 21). The best fitting femoral component in the M/L plane will be as follows: Width of femur at widest point: Size mm Small 54 Small+ 59 Medium 62 Standard 65 Standard+ 70 Large 75 Large+ 81 It is advisable to mark the center line for the femur at this point as it will subsequently help define the location of the femoral I.M. hole. 11 DePuy Synthes Joint Reconstruction LCS COMPLETE Surgical Technique

17 FEMORAL PREPARATIONˇ (figure 22) (figure 23) (figure 24) Attach the guide yoke to the appropriate size A/P femoral resection guide (Figure 22). Slip the yoke beneath the muscle anteriorly on the periosteum. Establish the center of the I.M. canal by positioning the yoke centrally on the anterior femoral shaft (Figure 23). Center the guide between the epicondyles (Figure 24). Surgical Technique LCS COMPLETE DePuy Synthes Joint Reconstruction 11

18 FEMORAL ROTATION DETERMINATION AND FLEXION BALANCING (figure 25) (figure 26) (figure 27) The centering mark that was previously drawn will be helpful. In this position, the only contact between the resection guide and the distal femoral condyles may be on the posterior medial condyle. The position of the femoral guide hole is generally 3 to 5 mm medial to the apex of the intercondylar notch (Figure 25). Place one temporary pin in any of the femoral resection guide holes for stability. Drill the femoral I.M. guide hole using a 9 mm diameter initiator drill (Figure 26). Remove the temporary pin and yoke. Insert the 7 in. long, 9 mm diameter rod. Slide the femoral guide positioner into the joint space, engaging the slot of the femoral A/P resection guide (Figure 27). Slightly flex or extend the knee until the positioner lies flat on the previously resected proximal tibia. If the positioner will not fit into the joint space, use the tibial fixation pins to realign the tibial resection block by selecting a more proximal row of holes on the block, lowering the block and removing additional proximal tibial bone. 11 DePuy Synthes Joint Reconstruction LCS COMPLETE Surgical Technique

19 12.5 mm 15.0 mm 17.5 mm 20.0 mm (figure 28) (figure 29) If the positioner does not fit snugly into the joint space, add tibial spacer shims and reassess until equal medial and lateral collateral ligament tension is achieved (Figure 28). Evaluate tibial alignment once more by sliding the external alignment rod through the femoral positioner (Figure 29). Evaluate femoral rotation prior to pinning the resection guide in place. It is customary to implant the femoral component in relative external rotation. In this system, however, specific external rotation is defined by the femoral guide positioner, which also establishes equal compartmental tension. The goal is to establish a quadrilateral space with the resected posterior femoral condylar surfaces parallel to the resected tibial surfaces when the collateral ligaments are tensioned. Pin the femoral A/P resection guide in two places, using the middle holes in the lower set of holes. Remove the femoral guide positioner. Surgical Technique LCS COMPLETE DePuy Synthes Joint Reconstruction 11

20 A/P FEMORAL RESECTION (figure 30) (figure 31) Attach the saw capture and cut the anterior and posterior femoral condyles. The anterior resection is flush with the anterior cortex of the femur (Figure 30). Once the resections are completed, remove the guide and pins. Insert the spacer block assembly into the flexion gap. The assembly mimics the thickness of the femoral, tibial and 10 mm bearing components. Assure equal medial and lateral compartmental tension. If necessary, add a tibial shim to the spacer block to fill the gap. The fixation pin hole pattern on the A/P femoral resection guides is the same distance from the anterior cutting surface regardless of component size. Thus, the anterior femoral resection will remain flush with the shaft if downsizing is performed. Therefore, resection of additional posterior condylar bone is simplified. Note: If one compartment is still too tight in flexion, release additional soft tissue to achieve equal compartmental tension. Note that this will affect extension alignment. Insert the external alignment rod through the spacer block handle to again check the frontal and lateral plane alignment on the tibia (Figure 31). Make note of the thickness of the spacer block utilized to fill the flexion gap. This will subsequently determine the extension gap. 11 DePuy Synthes Joint Reconstruction LCS COMPLETE Surgical Technique

21 DISTAL FEMORAL RESECTION Calibrated stop (figure 32) Intercondylar notch contact point (figure 33) Select a distal femoral cutting block that corresponds to the preoperatively determined valgus correction angle (3, 4, 5 or 6 degrees). Attach the cutting block to the distal femoral cutting guide with the correct indication, Right or Left, facing up. Move the block until it abuts the calibrated stop on the alignment guide. The arrow at the top of the block will point to the corresponding arrow on the alignment guide. Lock the cutting block into place by turning the wing nut 45 degrees clockwise. The 5 degree cutting block will allow a cut of 5 degrees of valgus that is approximately 3 mm proximal to the intercondylar notch. The 3 mm matches the thickness of the femoral component in that area. It is recommended by the author that the following valgus angles be used based on the patient s height: Height < 5 11 Height Height > degrees 4 degrees 3 degrees The depth of the distal cut can be fine-tuned by turning the wing nut 45 degrees counterclockwise to the neutral position, flipping up the calibrated stop and sliding the block proximally or distally on the arm of the alignment guide (Figure 32). Incremental markers of 2 mm are provided for this adjustment. With the cutting block locked into place, insert the 8 mm femoral I.M. rod into the distal femoral cutting guide assembly (Figure 33). Surgical Technique LCS COMPLETE DePuy Synthes Joint Reconstruction 11

22 Two Finger Breadths (figure 34) (figure 35) The rod is fluted and 1 mm smaller than the pilot hole to minimize pressure build-up in the canal and to allow the isthmus to dictate rod placement. Slowly advance the femoral I.M. rod into the distal femur. Full seating is not necessary as the rod may reach the isthmus. The blunt tip will easily pass into the I.M. canal while minimizing the chances of perforation (Figure 34). The modular cutting block should rest flush on the anterior femoral cut. Secure it in place by predrilling and inserting two pins through the marked center row of holes. Disengage the alignment guide from the cutting block by turning the wing nut to the neutral position. Remove both the I.M. rod and the alignment guide, leaving the block in place (Figure 34). Verify varus/valgus alignment by using the external alignment tower (Figure 35). With the femur in extension and in neutral rotation, correct alignment is indicated when the proximal end of the external alignment rod is centered over the head of the femur, or approximately two finger breadths medial to the anterior superior iliac spine. If alignment is found to be other than desired, the valgus angle can be altered by two degrees with the use of a two degree varus/valgus cutting block. If more correction is necessary, then choose another cutting block, mount it on the I.M. guide and reposition it on the anterior cut. 22 DePuy Synthes Joint Reconstruction LCS COMPLETE Surgical Technique

23 Traction (figure 36) (figure 37) (figure 38) (figure 39) To ensure the correct depth of the distal-femoral cut, have an assistant place traction on the ankle with the knee in extension. Place a spacer block parallel with the tibial cut and the anticipated femoral cut (Figure 36). To ensure accuracy, the tibial cutting block may be repositioned on the retained tibial pins, flush against the resected tibia. Apply a shim to the spacer block if it was used in determining the flexion gap. The extension gap must equal the flexion gap. If the spacer block is parallel and aligns with the tibial cut while medial and lateral tissues are equally tensioned, the distal femoral cutting block is correctly located. The cutting block can be positioned in a different row of holes (2.5 mm apart) to resect a greater or lesser amount of distal femur to assure the spacer block will fit in the extension gap. Note: Before proceeding, if necessary, correct either the distal-femoral or proximal-tibial cut to assure equal flexion and extension gaps. The distal femoral cut will affect the extension gap; the tibial resection will affect both flexion and extension gaps. The extension gap must equal the flexion gap. Attach the saw capture and cut the distal femur (Figure 37). Extend the knee and insert the spacer block (with the shim if it was used for the flexion gap). It should fit snugly in the gap with equal MCL and LCL tension (figs 38 and 39). Remove the spacer block and fixation pins. Surgical Technique LCS COMPLETE DePuy Synthes Joint Reconstruction 22

24 FEMORAL FINISHING RESECTION (figure 42) (figure 40) (figure 43) (figure 41) (figure 44) Flex the knee. Center the finishing guide between the epicondyles and impact it until fully seated. The finishing guide is the exact width of the corresponding femoral component size. Use fixation pins to secure the guide to the femur (Figure 40). Ensure the anterior and distal surfaces are flush. Cut the anterior and posterior chamfers with the oscillating saw (Figure 41). Using the 1/4 in. diameter stop drill, create two 3/4 in. deep holes through the distal guide holes (Figure 42). Using an osteotome or a narrow oscillating saw, make the recessing cut from the proximal end of the finishing guide. Save this bone to fashion a cone to plug the femoral I.M. hole. Use a power saw or osteotome to resect the posterior femoral condyle remnants to assure adequate flexion clearance (Figure 43). Remove the finishing guide. After all femoral cuts have been made, check again for maximal bone prosthesis contact using the femoral template (Figure 44). 22 DePuy Synthes Joint Reconstruction LCS COMPLETE Surgical Technique

25 TIBIAL PLATEAU PREPARATION CENTRAL STEM PREPARATION Drill Bushing (figure 45) (figure 46) (figure 47) (figure 48) Connect the tibial tray alignment handle to the MBT tray trial by retracting the lever, inserting the two pins into the anterior portion of the tray trial and releasing the lever (Figure 45). With the knee in full flexion and the tibia subluxed anteriorly, place the tray trial onto the resected tibial surface. Select the tray size that maximizes proximal tibial coverage without tibial overhang (Figure 46). ANY size tray can be used with any size tibial insert since the insert cone is the same for all sizes. Note: Excessive malrotation of the tibial tray, relative to the femoral component, can result in insert overhang and potential impingement on soft tissue.refer to the femoral/tibial sizing matrix on page 28 to assure adequate rotation with the chosen tibial and insert components. Mark rotational alignment of the MBT tray trial with electrocautery on the anterior tibial cortex to aid in permanent tibial tray implantation (Figure 47). Note: Tibial tray rotation is usually centered on the junction between the medial and central one-third of the tibial tubercle. Secure the tray with two fixation pins inserted through the recessed holes. Alternatively, the tray trial may be fixed to the proximal tibia using the two posterior spikes on the MBT drill bushing (Figure 48). Seat the MBT drill bushing into the tibial tray trial by lightly tapping the top of the drill bushing. Surgical Technique LCS COMPLETE DePuy Synthes Joint Reconstruction 22

26 Selected Tray Size Selected Tray Size (figure 49) (figure 50) Note: The MBT drill creates a cavity that is line-to-line with the punch bushing and final implant. Cement will interdigitate as the tray is implanted. If a larger cement mantle is desired, see Table A. The porous tray will create an interference fit of 1.6 mm around the entire central stem when fully impacted. In cases where the proximal tibial bone is sclerotic, drill two small holes posteriorly to facilitate the placement of the spikes on the drill bushing onto the tray trial. Use of MBT Stem Punch For Non Cemented Application: Advance the MBT stem punch into the drill bushing and impact it into the cancellous bone until the appropriate tray size marking is reached (Figure 49). In the case of sclerotic proximal tibial bone, introduce the drill into the drill guide first to begin the hole to facilitate the stem punch. Use of MBT Stem Drill: Assemble the drill stop onto the MBT drill and position it at the selected tray size. Advance the MBT Table A: Creating Central Stem Cement Mantle drill through the MBT drill bushing and into the cancellous bone until it hits the drill stop (Figure 50). Tray Size Drill Stop Setting Cement Mantle None (line-to-line fit) mm per side / 4 mm distal None (line-to-line fit) mm per side / 4 mm distal None (line-to-line fit) Drill bottoms out on tray trial 0.5 mm per side / 4 mm distal Note: If over-reaming is desired, remove the tray trial to avoid impingement of the reamer on the tray trial. To compact cancellous bone, advance the drill in reverse. 22 DePuy Synthes Joint Reconstruction LCS COMPLETE Surgical Technique

27 MBT TRAY PREPARATION MBT KEEL TRAY PREPARATION Unitized Punch Bushing Keel Punch Bushing (figure 51) (figure 52) (figure 53) MBT Tray Preparation: Assemble the universal handle to the appropriately sized MBT punch bushing (Figure 51). Impact this assembly into the cancellous bone until the shoulder of the bushing is in even contact with the MBT tray trial. Disconnect the universal handle, leaving the MBT punch bushing in place (Figure 52). MBT Keeled Tray Preparation (optional): Assemble the universal handle to the appropriately sized MBT keel punch bushing. Impact this assembly into the cancellous bone until the shoulder of the bushing is in even contact with the MBT tray trial. Disconnect the universal handle, leaving the MBT keel punch bushing in place (Figure 53). Surgical Technique LCS COMPLETE DePuy Synthes Joint Reconstruction 22

28 TRIAL REDUCTION Keel Punch (figure 54) (figure 55) (figure 56) Assemble the universal handle to the appropriately sized MBT keel punch and insert it into the MBT keel punch bushing, being careful to avoid malrotation (Figure 54). Impact this composite into the cancellous bone until the shoulder of the punch is in even contact with the MBT keel punch bushing (Figure 55). Disconnect the universal handle, leaving the MBT keel punch in place. Note: If the bone of the medial or lateral plateau is sclerotic, it is helpful to initially prepare the keel slot with an oscillating saw or high speed burr. Select the tibial insert trial that matches the chosen femoral size and thickness (as determined by spacer blocks) and slide it onto the MBT bushing on top of the tray trial (Figure 56). 22 DePuy Synthes Joint Reconstruction LCS COMPLETE Surgical Technique

29 (figure 57) (figure 58) Flex the knee 100 to 120 degrees and slide the femoral trial into position using the two peg holes and anterior surface for guidance (Figure 57). Avoid the tendency to place the trial in flexion. Extend the knee to 60 to 80 degrees of flexion and seat the femoral trial using the femoral impactor (Figure 58). Note the anterior/posterior stability, medial/lateral stability and overall alignment in the A/P and M/L plane. If there is any indication of instability, substitute a tibial insert trial with the next greater thickness and repeat reduction. Select the insert that gives the greatest stability in flexion and extension while still allowing full extension. The appropriate thickness bearing has been chosen when it cannot be removed with the femoral component in place and in 90 degrees of flexion. The rotating platform should not allow malrotation with the knee in flexion and with the femoral component in place. Flex and extend the knee while evaluating component function and stability. Check for: Adequate range of motion Equal flexion and extension gaps Proper ligamentous tension in extension and in flexion Correct mechanical alignment of the extremity Correct rotation of the tibial component Natural motion without restrictions Surgical Technique LCS 27 COMPLETE DePuy Synthes Joint Reconstruction 22

30 TIBIAL BEARING SELECTION Mobile Bearing Tibial (MBT) Tray - Sizing AP/ML (mm) Size 1 Size 1.5 Size 2 Size 2.5 Size 3 Size 4 Size 5 Size 6 Size 7 39/59 41/62 43/65 44/67 46/70 49/75 53/81 57/87 60/92 Small 35/53 COMPLETE RP LCS COMPLETE RP Tibial Inserts - Sizing AP/ML (mm) Small+ 39/58 Medium 41/61 Standard 43/64 Standard+ 46/69 Large 49/74 COMPLETE RP COMPLETE RP COMPLETE RP COMPLETE RP COMPLETE RP Large+ 53/80 COMPLETE RP Tibial insert and tibial tray compatibility. Rotating platform tibial inserts must match femoral components size-to-size. Bearing size is critical. The bearing size must match the femoral size to maintain congruency. 22 DePuy Synthes Joint Reconstruction LCS COMPLETE Surgical Technique

31 PATELLAR RESECTION (figure 59) (figure 60A) (figure 60B) Free the synovial tissue and retinaculum from the periphery of the patella down to the plane of the quadriceps tendonand patellar tendon reflection. Measure the patellar thickness. Resect the patellar articular surface parallel to and at the level of the quadriceps tendon attachment (Figure 59). Resect articular bone thickness approximately equal to the implant s overall thickness. There should be equal amounts of bone remaining in the medial/lateral and superior/inferior portions of the patellar remnant. A remnant of at least 13 mm thickness is suggested. Resection of the patella can also be accomplished by using the patellar resection guide (figs 60A/B). Set the reference arm of the resection guide to the appropriate size, which will allow for the proper resection for the patellar implant. LCS 3-Peg Patellar Thickness Chart Implant Thickness Size (mm) Metal-Backed All Polyethylene Small Small Medium Standard Standard Large Large Surgical Technique LCS COMPLETE DePuy Synthes Joint Reconstruction 22

32 PATELLAR TRIAL (figure 61) (figure 62) Place the thin patellar template that matches the femoral component s size over the trial femoral component and perpendicular to the long axis of the extremity with pegs pointing upward (Figure 61). Reduce and press the resected patella onto the template, engaging the pegs in the resected patellar surface. Flex the knee and assure that the patellar template remains perpendicular to the long axis of the extremity and parallel to the prosthetic joint line. With the knee extended, evert the patella while pressing the template to the patellar remnant. The handle of the template will usually lie approximately degrees downward from the perpendicular (Figure 62). Mark the three pegs for the trial patellar component with the cautery or a marking pen. 33 DePuy Synthes Joint Reconstruction LCS COMPLETE Surgical Technique

33 (figure 63) (figure 64) Remove the template and press the trial patellar component onto the resected patellar surface in the same location as the patellar template (Figure 63). Reduce the patella. While flexing and extending the knee, evaluate patellar tracking. The metal portion of the patella should remain parallel with the knee joint. Make adjustments as necessary. Align the appropriate size thick patellar template over the mark on the patellar remnant, representing proper alignment. Prepare the three pegs using the femoral lug drill. Ensure that the peg holes are sufficiently deep to avoid any resistance to the three pegs of the final patellar component (Figure 64). Surgical Technique LCS COMPLETE DePuy Synthes Joint Reconstruction 33

34 NON-CEMENTED IMPLANTATION (figure 65) (figure 66) (figure 67) Remove the trials and implant the final components in the following order: MBT Tray LCS Complete RP Tibial Insert LCS Complete Femoral Component LCS Patellar Component MBT Tray Implantation Assemble the universal handle onto the tray impactor and carefully insert the MBT tray into the proximal tibia, avoiding malrotation (Figure 65). If the keeled MBT tray is selected, attention is required to ensure the implant keel aligns with the prepared bone. When the tray is fully inserted, impact the top of the universal handle with several mallet blows to seat the implant fully (Figure 66). Insert Implantation Carefully clear and remove any loose fragments or particulate from the implanted tibial tray. Anteriorize the proximal tibial for improved visualization and insert the appropriate size tibial insert into the MBT tray (Figure 67). 33 DePuy Synthes Joint Reconstruction LCS COMPLETE Surgical Technique

35 (figure 68) (figure 69) Femoral Component Implantation Plug the femoral medullary canal with cancellous bone. Assemble the femoral component to the prepared distal femur, taking care that the lead edges are advanced in equal measure in alignment with bone cuts (Figure 68). Fully seat the component with the femoral impactor and bring the knee into full extension to produce maximum axial pressure on the bone-implant interface (Figure 69). Surgical Technique LCS COMPLETE DePuy Synthes Joint Reconstruction 33

36 (figure 71) (figure 70) (figure 72) Patellar Implantation Insert the fixation pegs of the patellar component into the drill holes in the resected patellar surface (Figure 70). Assemble the patellar clamp with the appropriate size patellar head (Figure 71). Press the patellar anchoring plate flat against the anterior patella surface using the patellar clamp (Figure 72). 33 DePuy Synthes Joint Reconstruction LCS COMPLETE Surgical Technique

37 CEMENTED IMPLANTATION (figure 75) (figure 73) (figure 74) (figure 76) MBT Tray Implantation Thoroughly cleanse the entire site with pulsatile lavage. Prepare methyl methacrylate cement and apply it in its low viscous state by syringe or with digital pressure to assure maximum penetration into the trabecular bone. Assemble the universal handle onto the tray impactor and carefully insert the MBT tray into the proximal tibia avoiding malrotation (Figure 73). If the keeled MBT tray is selected, attention is required to ensure the implant keel aligns with the prepared bone. When the tray is fully inserted, impact the top of the universal handle with several mallet blows to seat the implant fully (Figure 74). At this point, the surgeon may elect to assemble the RP trial plateau post and the tibial insert trial onto the seated MBT tray and the trial femoral component onto the prepared femur (Figure 75). Place the knee in degrees of flexion and apply axial compression to maintain equal pressure at the bone-to-tibial implant interface until the cement has set. Then place the knee in full flexion, remove the trials and carefully excise all extruded cement. Tibial Insert Implantation Carefully clear and remove any loose fragments or particulate from the permanent tibial tray. Anteriorize the proximal tibial for improved visualization and insert the appropriate size tibial insert into the MBT tray (Figure 76). Surgical Technique LCS COMPLETE DePuy Synthes Joint Reconstruction 33

38 (figure 77) (figure 78) Femoral Component Implantation Plug the femoral medullary with cancellous bone. Apply methyl methacrylate cement to all cut surfaces and press it into the cancellous bone at the anterior, anterior chamfer and distal chamfer surfaces and onto the femoral component at the posterior chamfer and posterior condylar recesses. Care is taken to avoid the articular surface of the implant. As the component is implanted, ensure that the lead edges are advanced in alignment with the bone cuts (Figure 77). Fully seat the femoral component with the femoral impactor and clear any extruded cement (Figure 78). Bring the knee into full extension to produce maximum axial pressure on the bone-cement interface until the cement has polymerized. Then place the knee in flexion and excise all remaining extruded cement with an osteotome. 33 DePuy Synthes Joint Reconstruction LCS COMPLETE Surgical Technique

39 (figure 80) (figure 79) (figure 81) Patellar Implantation Apply methyl methacrylate cement to the prepared patellar surface. Insert the fixation pegs of the patellar component into the drill holes in the resected patellar surface (Figure 79). Assemble the patellar clamp with the appropriate size patellar head (Figure 80). Press the patellar anchoring plate flat against the anterior patella surface using the patellar clamp (Figure 81). Surgical Technique LCS COMPLETE DePuy Synthes Joint Reconstruction 33

40 Final Implant Evaluation Reduce the patella and evaluate the implants. Ensure that unrestricted range of motion, free bearing movement and proper patellar tracking are occurring (Figure 82). (figure 82) Closure, Drains, Dressing Use the surgeon s preferred procedure. Closure in moderate flexion is recommended. Post-operative Management Use the surgeon s preferred procedure. 33 DePuy Synthes Joint Reconstruction LCS COMPLETE Surgical Technique

41 ORDERING INFORMATION DePuy MBT Trays Cat No. Description Cemented, Size Cemented, Size Cemented, Size Cemented, Size Cemented, Size Cemented, Size Cemented, Size Cemented, Size Cemented, Size POROCOAT, Size POROCOAT, Size POROCOAT, Size POROCOAT, Size POROCOAT, Size POROCOAT, Size POROCOAT, Size POROCOAT, Size POROCOAT, Size 7 DePuy MBT Trays - With Keel Cat No. Description Cemented, Size Cemented, Size Cemented, Size Cemented, Size Cemented, Size Cemented, Size Cemented, Size Cemented, Size Cemented, Size POROCOAT, Size POROCOAT, Size POROCOAT, Size POROCOAT, Size POROCOAT, Size POROCOAT, Size POROCOAT, Size POROCOAT, Size POROCOAT, Size 7 LCS COMPLETE Femoral Components Cat No. Description Cemented, Right, Small Cemented, Right, Small Cemented, Right, Medium Cemented, Right, Standard Cemented, Right, Standard Cemented, Right, Large Cemented, Right, Large Cemented, Left, Small Cemented, Left, Small Cemented, Left, Medium Cemented, Left, Standard Cemented, Left, Standard Cemented, Left, Large Cemented, Left, Large POROCOAT, Right, Small POROCOAT, Right, Small POROCOAT, Right, Medium POROCOAT, Right, Standard POROCOAT, Right, Standard POROCOAT, Right, Large POROCOAT, Right, Large POROCOAT, Left, Small POROCOAT, Left, Small POROCOAT, Left, Medium POROCOAT, Left, Standard POROCOAT, Left, Standard POROCOAT, Left, Large POROCOAT, Left, Large+ 3-Peg Metal-Backed Patella Cat No. Description Cemented, Small Cemented, Small Cemented, Medium Cemented, Standard Cemented, Standard Cemented, Large Cemented, Large POROCOAT, Small POROCOAT, Small POROCOAT, Medium POROCOAT, Standard POROCOAT, Standard POROCOAT, Large POROCOAT, Large+ 3-Peg All-Polyethylene Patella Cat No. Description Cemented, Small Cemented, Small Cemented, Medium Cemented, Standard Cemented, Standard Cemented, Large Cemented, Large+ Surgical Technique LCS COMPLETE DePuy Synthes Joint Reconstruction 33

42 LCS COMPLETE RP Tibial Inserts Cat No. Description Small, 10 mm Small, 12.5 mm Small, 15 mm Small, 17.5 mm Small, 20 mm Small+, 10 mm Small+, 12.5 mm Small+, 15 mm Small+, 17.5 mm Small+, 20 mm Medium, 10 mm Medium, 12.5 mm Medium, 15 mm Medium, 17.5 mm Medium, 20 mm Standard, 10 mm Standard, 12.5 mm Standard, 15 mm Standard, 17.5 mm Standard, 20 mm Standard+, 10 mm Standard+, 12.5 mm Standard+, 15 mm Standard+, 17.5 mm Standard+, 20 mm Large, 10 mm Large, 12.5 mm Large, 15 mm Large, 17.5 mm Large, 20 mm Large+, 10 mm Large+, 12.5 mm Large+, 15 mm Large+, 17.5 mm Large+, 20 mm Tibial Preparation Cat No. Description MBT Tray Trial, Size MBT Tray Trial, Size MBT Tray Trial, Size MBT Tray Trial, Size MBT Tray Trial, Size MBT Tray Trial, Size MBT Tray Trial, Size MBT Tray Trial, Size MBT Tray Trial, Size MBT Keelpunch, Size MBT Keelpunch, Size Keelpunch Bushing Extractor MBT Keelpunch Bushing, Size MBT Keelpunch Bushing, Size MBT Keelpunch Bushing, Size MBT Punch Bushing, Size MBT Punch Bushing, Size MBT Punch Bushing, Size MBT Central Drill MBT Non-Cemented Stem Punch/Drill MBT Drill Bushing MBT Plateau Trial Post MBT Tray Impactor MBT Tray Trial Fixation Pins Tibial Tray Alignment Handle SPECIALIST 2 Universal Handle MBT Evaluation Bullet, Size MBT Evaluation Bullet, Size DePuy Synthes Joint Reconstruction LCS COMPLETE Surgical Technique

43 LCS COMPLETE Trial Femoral Components Cat No. Description Right, Small Right, Small Right, Medium Right, Standard Right, Standard Right, Large Right, Large Left, Small Left, Small Left, Medium Left, Standard Left, Standard Left, Large Left, Large+ LCS COMPLETE RP Insert Trials Cat No. Description Small, 10 mm Small, 12.5 mm Small, 15.0 mm Small, 17.5 mm Small, 20.0 mm Small+, 10 mm Small+, 12.5 mm Small+, 15.0 mm Small+, 17.5 mm Small+, 20.0 mm Medium, 10 mm Medium, 12.5 mm Medium, 15.0 mm Medium, 17.5 mm Medium, 20.0 mm Standard, 10 mm Standard, 12.5 mm Standard, 15.0 mm Standard, 17.5 mm Standard, 20.0 mm Standard+, 10 mm Standard+, 12.5 mm Standard+, 15.0 mm Standard+, 17.5 mm Standard+, 20.0 mm Large, 10 mm Large, 12.5 mm Large, 15.0 mm Large, 17.5 mm Large, 20.0 mm Large +, 10 mm Large +, 12.5 mm Large +, 15.0 mm Large +, 17.5 mm Large +, 20.0 mm 3-Peg Mobile-Bearing Patella Trials Cat No. Description With Pegs, Small With Pegs, Small With Pegs, Medium With Pegs, Standard With Pegs, Standard With Pegs, Large With Pegs, Large With Pins, Small With Pins, Small With Pins, Medium With Pins, Standard With Pins, Standard With Pins, Large With Pins, Large+ 3-Peg Polyethylene Patella Trials Cat No. Description With Pegs, Small With Pegs, Small With Pegs, Medium With Pegs, Standard With Pegs, Standard With Pegs, Large With Pegs, Large With Pins, Small With Pins, Small With Pins, Medium With Pins, Standard With Pins, Standard With Pins, Large With Pins, Large+ Surgical Technique LCS COMPLETE DePuy Synthes Joint Reconstruction 44