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This report is being submitted pursuant to the provisions of 21 cfr, part 803.This report may be based on information which has not been investigated or verified prior to the required reporting date.This report does not reflect a conclusion by depuy synthes, or its employees that the report constitutes an admission that the product, depuy synthes, or its employees caused or contributed to the potential event described in this report.If information is obtained that was not available for the initial report, a follow-up report will be filed as appropriate.H11 additional narrative: results received from the engineering team: investigation summary: the investigation could not confirm the reported issue of " the posterior lateral femoral cut stated that they were cutting 8mm but it looked around 2mm." the issue was investigated and reviewed by the systems team.Issue #1: the posterior lateral femoral cut stated that they were cutting 8mm but it looked around 2mm the investigation found that the complaint of posterior lateral femoral inaccurate cut could not be confirmed since the pointer tool was not utilized to verify the resection planes.The investigation found that the most probable root cause of the reported issue is potential array movement, sub-optimal leg positioning, leg/robot movement, and sub-optimal landmark acquisition.The investigation found that the tibia and femur checkpoints were created on array itself, not on bone.Since the checkpoints were placed on the arrays, they lose their purpose and it would eventually be difficult to confirm if there was femur array movement as any array movement happens, the checkpoint also moves.The investigation found that there was significant array movement during multiple landmark acquisition steps and initial leg alignment steps before any cut steps performed.The investigation also found that there was significant array movement during posterior chamfer cut.The verify checkpoint was done before femur and tibia cuts began and were within system threshold limits, but never done verify checkpoint after completing all the femur and tibial cuts, so array movement could not be confirmed.While the exact cause of the array movement cannot be established, array movement is generally caused by the arrays not being securely attached.Please ensure the array is properly secured during the procedure to avoid array movement.If the verify checkpoint step cannot be completed, please do not continue the operation.Adjustments are not permitted after the first bone resection: if bone array movement occurs the reference frame becomes inaccurate.The robotic-assisted procedure must be aborted, and the procedure must be completed using conventional manual instruments (see appendix 1: ¿system troubleshooting¿).Use ¿verify checkpoint via toolbox¿ to confirm that the bone arrays have not moved.The investigation found that the posterior landmarks are on the edge of the point cloud.Likely meaning that there is a more posterior point for both landmarks.This could impact the sizing of the implant and the position of the posterior resection plane leading to a larger posterior cut than intended.The investigation also found evidence of anterior cortex line being drawn sub optimally.When the anterior cortex line is acquired too laterally it can lead to the resection plane of the anterior cut being deeper than intended leading to a possible notch of the femur.The anterior cortex/reference point, derived from the anterior cortex line, determines the initial anterior-posterior (a-p) position of the femoral implant for an anterior referencing tka.The anterior cortex/reference point is also the location where the anterior resection plane will exit the femur.If the anterior cortex line is acquired too laterally the femur can notch on the lateral ridge of the trochlea.This is because the lateral ridge of the trochlea is often times more prominent anteriorly than the shaft of the femur.It can be useful to use the pointer tool to verify the position of the anterior resection plane, prior to cutting, by placing the pointer tool near the anterior resection plane in order to mitigate notching.The pointer array can be used to mimic the use of an "angel wing" where the system will display the distance between the pointer array tip and the resection plane.The ifu states, "a smooth line must be acquired with the pointer along the lateral surface of the anterior cortex.This line will later be used to calculate the anterior reference point which is where this line crosses the exit of the anterior cut plane in anterior referencing techniques".The investigation found that during all femur and tibia cut steps, the leg was likely not appropriately positioned relative to the robotic-assisted device.This may have made the cuts difficult for the robot to complete as the power being cut.The leg was in flexion at ~118 degrees to ~128 degrees of flexion during tibia and all femur cut steps, which likely lead to the movement of leg occurring more frequently during operation.¿ position the leg at the center of the device array interface at 25 mm (1 inch) below the femoral epicondyles.¿ place the knee in a stable position, flexed between 90 degrees and 110 degrees.¿ ensure the leg and the holding arm are both vertically aligned.¿ ensure the planned implant axis (and not the bone axis) is aligned with the device axis.The investigation found that during most of the femur cuts and tibia cuts, there was considerable leg/robot movement.The investigation found that "instruction: "[saw disabled] saw blade plane deviates too much from the cutting plane" message displayed during all the cut steps.This would cause power to the saw handpiece to be cut.The constant cutting of power while during the cut means movement is large enough that the system cuts power, this could lead to inaccurate cuts.During operation the robot moves rapidly.Robot movement is generally caused by the system not being properly mounted to the bedrail.The patient¿s leg must be stabilized during resections.The surgeon¿s preferred leg holder may be used to stabilize the leg if it does not inhibit the function of the velys robotic-assisted solution.Prior to each resection, ensure the leg is stabilized in the desired position.The ifu outlines: any large leg/robot movement will require a rapid adjustment by the robotic-assisted device and can potentially introduce inaccuracy.Issue # 2: the camera is intermittently seeing the arrays the investigation found that the most probable root cause of the reported issue is blocked arrays and the camera lens being soiled/not maintained.Per wo, camera lens fluid streak marks were cleaned and system is working fine.This indicates that multiple messages related to array visibility lost are due to camera lens being soiled or not maintained properly.The investigation found that there are multiple instances of blocked array messages popped up and multiple messages of "saw tracker visibility lost " and "target (bone" tracker visibility lost" displayed during femoral and tibia cut steps, this messages pops up because both saw array and bone array are not consistently visible to the camera.Please ensure that the required arrays for each step are fully visible to the camera.Blocking the arrays will result in the camera being unable to track the arrays.Ensure required arrays stay in the camera¿s line of sight without interference from the environment for the duration of the step.For example, the device sterile drape or an instrument may be in front of an array.In addition, or personnel or patient¿s non operative leg could be blocking an array.The system will prevent the saw from turning on if it is not able to determine the location of the saw array and relevant bone array at any point during the resection.If there are continuous issues with array visibility and/or saw power continuity throughout the procedure, adjust the camera so that the distal camera lens aligns with the knee center using either of the methods below.These actions should be completed by a non-sterile person.A) move the base station proximally along the bed (e.G.Towards the patient¿s chest).B) use the handle to move the articulated arm holding the camera proximally along the bed (e.G.Towards the patient¿s chest).If arrays become soiled with blood or other material during the procedure, use water and a soft, lint-free cloth to wipe the puresight¿ reflectors gently.If a new array is being brought into the camera¿s field of view, discard the original array of the same type per facility¿s biohazard procedure so that it is not detected by the camera.Adjust the or lighting or reposition reflective objects that may interfere with camera tracking.If an array continues to appear as not visible on the status bar, even after wiping away any fluid or tissue, the array must be replaced.For each array, respectively: - the device array may only be replaced before robotic-assisted device transfer to the bedrail.Robotic-assisted device check must be repeated - the bone arrays may only be replaced before any resections have been made.Checkpoint acquisition and landmark acquisition must be repeated - the saw array may be replaced at any time.Saw blade calibration must be repeated any time a new saw array is used - the pointer array may be replaced at any time.Consult your depuy synthes representative to arrange a return, if requested, or dispose of the old pointer array per hospital procedure and repeat pointer check with the new pointer array.Per wo, camera lens fluid streak marks -- camera cleaned.Testing passed.Logs pulled.Testing performed.System is ready for clinical use.Instructions there are no defects found with the system or software.The software was performing as intended.The user indicated that there was no negative impact to the patient outcome and no patient harm and the investigation indicates that the system was behaving properly.Root cause: issue #1: the investigation found that the most probable root cause of the reported issue is potential array movement, sub-optimal leg positioning, leg/robot movement, and sub-optimal landmark acquisition.However, the issue could not be confirmed because the pointer was not used to measure the cuts.Issue #2: the investigation found that the most probable root cause of the reported issue is blocked arrays and the camera lens being soiled/not maintained.This can be traced to improper handling by the user.There are no defects found with the system or software.The software was performing as intended.Additional complaint information monitoring for potential safety signals is conducted through complaint trending as part of post market surveillance.Device history review
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> no manufacturing record evaluation required as no manufacturer or service related issue found.
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