Zimmer MIS Multi-Reference Surgical Technique

Zimmer MIS Multi-Reference Surgical Technique Manual pdf 39 page image

Zimmer MIS Multi-Reference 4-in-1 Femoral Instrumentation Surgical Technique 37Step TenImplant ComponentsIn this step, the final components areimplanted, and the tibial articularsurface is secured to the implantedtibial base plate. When using cementedcomponents, it is recommended to usetwo batches of cement.After the implants have been chosen,make a final check to ensure that thefemoral, tibial base plate, and tibialarticular surface components match.If using a cemented component, mixthe first batch of cement. The cementshould have a doughy consistencywhen ready for use.Tibial Base PlateIf a stemmed tibial base plate will beused with a stem extension, attach thedesired stem extension to the stem andstrike it once with a mallet. If a 10mm-14mm thick tibial articular surface willbe used, insert the locking screw forthe stem extension.If a stemmed tibial base plate willbe used without a stem extension,consider the need for a taper plug. If a17mm or 20mm articular surface willbe used, a stem extension or taperplug is required. A taper plug also canbe used with the 10mm-14mm tibialarticular surface. If it is planned touse a 14mm articular surface or if theflexion and extension gaps are notbalanced, consider using the taper plugin case the final reduction reveals thatit is necessary to switch to a 17mm or20mm articular surface. Furthermore,if the articular surface should everrequire revision with a 17mm or 20mmthick component, the taper plug isalready in place and revision of thetibial base plate may not be necessary.Assemble the taper plug onto the tibialplate by striking it several times with amallet to allow the ring on the taper todeform.Position the PCL Retractor posteriorly,the Collateral Soft Tissue Protectorlaterally, and the Collateral Retractormedially. Sublux the tibia anteriorly.Place a layer of cement on theunderside of the tibial base plate,around the keel, on the resected tibialsurface and in the tibial IM canal.Position the tibial base plate onto thetibia and use the Tibial Impactor toimpact it until fully seated (Fig. 10a).Thoroughly remove any excess cementin a consistent manner.Femoral ComponentAttach the femoral component to theFemoral Impactor/Extractor.Knee in 70°-90° flexionPlace the Collateral Retractor laterally,an Army-Navy retractor anteriorly, anda rake retractor on the meniscalbed medially.Place a layer of cement on theunderside of the prosthesis and in theholes drilled in the femur.Attach the Femoral/Impactor/Extractorto the femoral component. Insert thefemoral component onto the distalfemur by translating the componentlaterally until the lateral peg alignswith the drill hole in the lateral femoralcondyle. Take care to avoid scratchingthe implant component surfaces.Disposable, plastic Tibial PlateProtectors may be temporarily insertedonto the Tibial Base Plate to protectthe implant surfaces during insertionof the femoral component. Remove theTibial Plate Protector after the femur isseated. Be sure that soft tissue is nottrapped beneath the implant. Use amallet to impact the component untilfully seated.Remove the Femoral Impactor/Extractor, and the retractors. Checkthe medial and lateral sides to makesure the femoral component is fullyimpacted. Remove any excess cementin a thorough and consistent manner.Alternatively, push the component inplace by hand beginning laterally, thenmedially.Fig. 10a Use the Tibial Impactor to impactthe tibial base plate.