Summary The ROSA® Knee System is indicated for use as a stereotaxic instrumentation system in total knee replacement surgery to assist in the accurate placement of compatible fixed-bearing knee implant components. It achieves this through a robotic arm, an optical tracking system, and software that provide software-defined spatial boundaries and orientation information based on intra-operatively recorded anatomical landmarks. This platform is used during primary total knee arthroplasty for skeletally mature patients to enhance alignment accuracy and facilitate intra-operative joint balancing. Related Implants Persona® The Personalized Knee® restores a neutral mechanical axis while addressing specific patient needs through versatile constraint options, including cruciate retaining or posterior stabilized designs Indications Indications Total knee replacement surgery software-defined spatial boundaries for orientation and reference information to identifiable anatomical structures for accurate placement of knee implant components Contraindications significant bone loss severely limiting range of motion active infection of the knee joint area knee replacement revision surgery Anatomy Osteology femoral head center femoral axis point posterior condyles anterior and posterior trochlear groove points medial and lateral epicondyles Muscles vastus medialis muscle fibers Blood supply saphenous artery and vein, femoral artery and vein, and popliteal artery and vein Approach Patient positioning patient is placed supine OR layout Robotic Unit is positioned approximately at the patient’s hip and approximately 45° relative to the surgical table Optical Unit is positioned on the opposite side of the surgeon and Robotic Unit Four OR configurations are supported right knee with surgeon on same side as operated knee right knee with surgeon opposite the operated knee left knee with surgeon on same side as operated knee left knee with surgeon opposite the operated knee Exposure incision and exposure are based on surgeon choice of technique Visibility and safety trackers must remain visible throughout landmarking, evaluation, and resections camera may be repositioned when needed except during femoral head center acquisition and bone tracking Technique Case setup case is created and tracked through ZB Edge Case Portal® and uploaded to the ROSA® Knee System before surgery case is launched from the Robotic Unit using a USB drive and case management application incorrect case information requires quitting and relaunching the correct case Image-based workflow pre-operative X-rays are used to reconstruct a patient-specific 3D bone model X-Atlas® 2D to 3D technology is used to generate the virtual femur and tibia model Imageless workflow surgeon may elect not to plan the case before the surgery date generic bone schematics are displayed in the user interface imageless planning is performed intra-operatively Setup and registration ROSA Arm Instrument Interface is installed and Force Sensor is calibrated ROSA Base Reference Frame and ROSA Arm Reference Frame are installed Robotic Unit is aligned with the operative leg axis and knee joint line Optical Unit laser is aimed at the NavitrackER on the ROSA Arm Reference Frame during camera setup OptimiZe Landmarking™ distal femoral condyle painting is used to capture the most distal condylar regions tibiofemoral contact points in flexion and extension are used for knee-state and gap assessment Biomechanical Contact Post is described as creating a starting point for extension and flexion laxity assessment landmarking features are intended to reduce user landmarking variability and support consistent landmark positions OptimiZe Planning™ OptimiZe Planning™ automatically positions Persona® Knee implants based on a selected surgeon profile feature is available only for Persona® implants selected profile proposes a plan that best matches profile requirements OptimiZe Kinematic Alignment™ feature provides an automated Kinematic Alignment plan based on bony landmarks femoral wear evaluation uses distal and posterior condylar cartilage and bone wear tibial wear evaluation uses medial and lateral tibial plateau wear where PTA references were taken LDFA and MPTA are displayed when Kinematic Alignment is active and landmarking is completed OptimiZe Tracking™ with Active Track™ Active Track™ enables collaborative resections without pinning the Cut Guide to bone for selected femoral distal and tibial proximal resections Active Track™ is disabled by default when enabled, Robotic Arm remains in Collaborative mode during the corresponding resection Active Track™ allows bony resections to remain on plane with leg movement key precautions include soft-tissue protection, leg stability, visible NavitrackERs, and continuous Foot Pedal pressure during resection workflow can revert to pinning at any time during the Active Track™ resection flow OptimiZe Experience™ simplified interface allows selection of workflow and display options surgeon can tailor which information is displayed for each case viewing options can be set pre-operatively through ZB Edge Case Portal® Resections entry APPROVE PLAN opens the RESECTIONS panel Cut Guide Checkpoint verifies registration and correct ROSA TKA Cut Guide installation Bone Reference Checkpoint verifies femoral and tibial reference stability when selected user can start with femoral distal or tibial proximal resection direct panel access is disabled while in a resection flow ROSA HOME is not accessible during a resection flow unless the flow is cancelled Femoral distal resection Arm transitions to Collaborative mode near the cut plane pins are placed through FEMUR holes, with optional oblique pin for additional stability resection is performed and validated with the Universal Validation Tool Body pins are removed after resection Tibial proximal resection Arm transitions to Collaborative mode near the cut plane pins are placed through TIBIA holes, with optional oblique pin for additional stability Active Track™ workflow allows tibial proximal resection without pinning if enabled Femoral 4-in-1 positioning accessible after distal femoral resection is completed medial 4-in-1 pin is placed first and live cut values are reviewed lateral 4-in-1 hole is drilled after confirmation final 4-in-1 bone resections are performed with the appropriate standard finishing guide according to implant system technique Final evaluation and data confirmation final Knee State Evaluation can be performed with trials or final implants in place final case data review includes implant brand, component type and size, bearing thickness, bearing type, final HKA, and Knee State Evaluation data can be saved with trial components, saved with final implants, or not saved Removal of instrumentation Checkpoint Screws are removed if the checkpoint workflow was used Bone Reference set screws are loosened with a 3.5 mm screwdriver Bone References are removed from Fix Fluted Pins Fix Fluted Pins are removed from bone using a power tool on reverse setting bending pins during removal should be avoided Technical specifications System components Robotic Unit Robotic Arm Touchscreen immobilization system Foot Pedal computer software Optical Unit Optical Camera Touchscreen camera positioning arm Tracking Optical tracking uses NavitrackER devices mounted to tracked instruments and references NavitrackER devices are single use and must not be resterilized bone references must remain stable throughout the case Bone Reference Checkpoint can be used to verify femoral and tibial reference stability after landmarking Foot Pedal functions enables Robotic Arm movement interruption stops Robotic Arm movement Planning limits Parameter Femur Limits Tibia Limits Varus/Valgus NexGen® / Vanguard®: 5.0° varus to 5.0° valgus Persona®: 10.0° to 10.0° valgus NexGen® / Vanguard®: 5.0° varus to 5.0° valgus Persona®: 10.0° varus to 10.0° valgus Flexion / Slope 3.0° extension to 8.0° flexion 5.0° anterior to 12.0° posterior slope Resection Depth 1.0 mm to 18.0 mm (from most prominent distal condyle) 2.0 mm to 14.0 mm (from highest tibial plateau) Axial Rotation 3.0° internal to external (relative to PCA) 20.0° internal to 15.0° external Product security system functions in kiosk mode for end users access is restricted to case manager application and clinical application patient information is hosted on an encrypted drive extracted data are encrypted in transit or password-protected system does not support wireless network connectivity Ethernet port is used only for communication with the Optical Unit