MAUDE Adverse Event Report: STRYKER ORTHOPAEDICS-MAHWAH TRITANIUM PATELLA-ASYMMETRIC; PROSTHESIS, KNEE, PATELLO/FEMOROTIBIAL, SEMI-CONSTRAINED, UNCEMENTED, POROUS, CO

Model Number	5531-G-211-E
Medical Device Problem Codes	Adverse Event Without Identified Device or Use Problem (2993); Unintended Movement (3026)
Health Effect - Clinical Codes	Ambulation or Postural Difficulties (2544); Insufficient Information (4580)
Date of Event	09/08/2022
Type of Reportable Event	Serious Injury
Event or Problem Description
It was reported that the patient's left knee was revised.Reason for revision was not reported to the rep, but x-rays were provided.A baseplate, insert, and patellar component were revised.
Additional Manufacturer Narrative
It was noted that the device is not available for evaluation.Should additional information become available, it will be provided in a supplemental report upon completion of the investigation.Review of the device history records indicate devices were manufactured and accepted into final stock with no relevant reported discrepancies.There have been no other similar events for the lot referenced.The following devices were also listed in this report: device name#tritanium bplate triathlon s2 ; cat#5536b200 ; lot#ctd75316, device name#tritanium patella-asymmetric ; cat#5552-l-320 ; lot#y1p71, it cannot be determined which, if any of these devices may have caused or contributed to the patient's experience.
Event or Problem Description
It was reported that the patient's left knee was revised."a patella component which has displaced from the bone and a tibial component which appears subsided and in extension".A baseplate, insert, and patellar component were revised.
Additional Manufacturer Narrative
Reported event: an event regarding subsidence involving a triathlon patella was reported.The event was confirmed via clinician review of the provided medical records.Method & results: product evaluation and results: material analysis, visual, functional and dimensional inspections could not be performed as the device was not returned.Clinician review: a review of the provided medical records by a clinical consultant indicated: this patient underwent a cementless, robotically assisted cruciate retaining total knee arthroplasty with patella resurfacing.Approximately three months later revision was necessary for displacement of the tibia and patella.I can confirm that this occurred since i was able to view the x-rays showing the displaced components.I cannot confirm that the event of revision occurred since i have no documentation for it such as office notes, operation note, or x-rays following the revision.The root cause of this event cannot be determined with certainty.However, in my opinion and experience, displacement of two components within a three month period after surgery is unusual and i would implicate surgical technique as a likely cause.I don't believe that this type of displacement can be attributed to patient activity level or weight.If the implant record is correct, the surgeon used a cruciate stabilized insert with a cruciate retaining femoral component.This would need to be clarified as that would be not compatible with proper function.Operation reports for the index and revision surgery would help to clarify this.I would not assign any causality to the implant itself.Product history review: review of the device history records indicate devices were manufactured and accepted into final stock with no relevant reported discrepancies.Complaint history review: there have been no other similar events for the lot referenced.Conclusions: a review of the provided medical records by a clinical consultant indicated: this patient underwent a cementless, robotically assisted cruciate retaining total knee arthroplasty with patella resurfacing.Approximately three months later revision was necessary for displacement of the tibia and patella.I can confirm that this occurred since i was able to view the x-rays showing the displaced components.I cannot confirm that the event of revision occurred since i have no documentation for it such as office notes, operation note, or x-rays following the revision.The root cause of this event cannot be determined with certainty.However, in my opinion and experience, displacement of two components within a three month period after surgery is unusual and i would implicate surgical technique as a likely cause.I don't believe that this type of displacement can be attributed to patient activity level or weight.If the implant record is correct, the surgeon used a cruciate stabilized insert with a cruciate retaining femoral component.This would need to be clarified as that would be not compatible with proper function.Operation reports for the index and revision surgery would help to clarify this.I would not assign any causality to the implant itself.No further investigation for this event is possible at this time.If devices and/or additional information become available to indicate further evaluation is warranted, this record will be reopened.

• Brand Name: TRITANIUM PATELLA-ASYMMETRIC
• Common Device Name: PROSTHESIS, KNEE, PATELLO/FEMOROTIBIAL, SEMI-CONSTRAINED, UNCEMENTED, POROUS, CO
• Manufacturer (Section D): STRYKER ORTHOPAEDICS-MAHWAH; 325 corporate drive; mahwah NJ 07430
• Manufacturer (Section G): STRYKER ORTHOPAEDICS-CORK; ida industrial estate; carrigtwohill NJ NA ; EI NA
• Manufacturer Contact: arokiya raj ; 325 corporate drive; mahwah, NJ 07430 ; 2018315000
• MDR Report Key: 15527009
• Report Number: 0002249697-2022-01424
• Device Sequence Number: 19501772
• Product Code: MBH
• UDI-Device Identifier: 07613327336504
• UDI-Public: 07613327336504
• Combination Product (Y/N): N
• Initial Reporter State: IL
• Initial Reporter Country: US
• PMA/510(K) Number: K132624
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Device Implanted Year: 2022
• Device Explanted Year: 2022
• Reporter Type: Manufacturer
• Report Source: Health Professional
• Initial Reporter Occupation: Physician
• Type of Report: Initial,Followup
• Report Date (Section B): 12/21/2022

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Is this an Adverse Event Report?: Yes
• Is this a Product Problem Report?: No
• Operator of Device: Health Professional
• Device Model Number: 5531-G-211-E
• Device Catalogue Number: 5552-L-320
• Device Lot Number: Y1P71
• Was Device Available for Evaluation?: No
• Is the Reporter a Health Professional?: Yes
• Type of Report(Section G): Follow-Up
• Initial Date Received by Manufacturer: 09/08/2022
• Supplement Date Received by Manufacturer: 12/06/2022
• Initial Report FDA Received Date: 10/03/2022
• Supplement Report FDA Received Date: 12/21/2022
• Was Device Evaluated by Manufacturer? (Y/N): No
• Date Device Manufactured: 03/09/2022
• Is the Device Labeled for Single Use? (Y/N): Yes
• Is This a Single-Use Device that was Reprocessed and Reused on a Patient? (Y/N): No
• Usage of Device: Initial
• Patient Sequence Number: 1
• Outcome Attributed to Adverse Event: Required Intervention; Hospitalization
• Patient Age: 79 YR
• Patient Sex: Female
• Patient Weight: 67 KG