MAUDE Adverse Event Report: STRYKER ORTHOPAEDICS-MAHWAH TRIATHLON #4 CS ALLPOLY 9MM; PROSTHESIS, KNEE, PATELLO/FEMOROTIBIAL, SEMI-CONSTRAINED, UNCEMENTED, POROUS, CO

Catalog Number	5534A409
Medical Device Problem Codes	Mechanical Problem (1384); Adverse Event Without Identified Device or Use Problem (2993)
Health Effect - Clinical Codes	Loss of Range of Motion (2032); Fibrosis (3167)
Date of Event	08/14/2025
Type of Reportable Event	Serious Injury
Additional Manufacturer Narrative
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.An evaluation of the device cannot be performed as the device was not returned to the manufacturer.Should additional information become available it will be reported in a supplemental report upon completion of the investigation.
Event or Problem Description
Subject had primary ltka and was found to have limited rom at about 40 degrees despite physical therapy.Mua was performed getting extension to 125 degrees.Clinic visit post mua with rom at 120 degrees extension.
Event or Problem Description
No new information.
Additional Manufacturer Narrative
Reported event: an event regarding arthrofibrosis involving a triathlon insert was reported.The event was confirmed.Method & results: -product evaluation and results: material analysis, visual, functional, and dimensional inspections could not be performed as the device remained implanted.-clinician review: confirmation of event: i can confirm that the patient had a primary left total knee arthroplasty as described above since i was able to review the operation report and postoperative x-rays.I can also confirm that the patient underwent a manipulation and injection of the knee since i was able to review the operation report.Root cause analysis: the root cause of this event cannot be determined with certainty.The causes of arthrofibrosis following total knee arthroplasty are multi factorial including surgical technique in the way the implants are positioned and secured, whether or not the proper kinematics of the knee were restored and especially in a cruciate retaining implant, the proper treatment of the posterior cruciate ligament.Patient factors including adherence to the postoperative protocol for physical therapy and restoration of range of motion are important as well as the patient activity level, lifestyle and bmi.In addition, some patients are genetically prone to scar formation.I would not assign any causality to the implants themselves.-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.Conclusion: confirmation of event: i can confirm that the patient had a primary left total knee arthroplasty as described above since i was able to review the operation report and postoperative x-rays.I can also confirm that the patient underwent a manipulation and injection of the knee since i was able to review the operation report.Root cause analysis: the root cause of this event cannot be determined with certainty.The causes of arthrofibrosis following total knee arthroplasty are multi factorial including surgical technique in the way the implants are positioned and secured, whether or not the proper kinematics of the knee were restored and especially in a cruciate retaining implant, the proper treatment of the posterior cruciate ligament.Patient factors including adherence to the postoperative protocol for physical therapy and restoration of range of motion are important as well as the patient activity level, lifestyle and bmi.In addition, some patients are genetically prone to scar formation.I would not assign any causality to the implants themselves.No further investigation for this event is possible at this time.If additional information become available to indicate further evaluation is warranted, this record will be reopened.

• Brand Name: TRIATHLON #4 CS ALLPOLY 9MM
• 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-LIMERICK; raheen business park; limerick NA ; EI NA
• Manufacturer Contact: anna ryan ; raheen business park; limerick NA ; EI NA ; 61498200
• MDR Report Key: 23000675
• Report Number: 0002249697-2025-00960
• Device Sequence Number: 9619796
• Product Code: MBH
• UDI-Device Identifier: 07613327043259
• UDI-Public: 07613327043259
• Combination Product (Y/N): N
• Initial Reporter State: NY
• Initial Reporter Country: US
• PMA/510(K) Number: K141056
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Device Implanted Year: 2017
• Reporter Type: Manufacturer
• Report Source: Health Professional
• Initial Reporter Occupation: Physician
• Type of Report: Initial,Followup
• Report Date (Section B): 10/29/2025

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 Expiration Date: 07/31/2022
• Device Catalogue Number: 5534A409
• Device Lot Number: 362871
• 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: 08/14/2025
• Supplement Date Received by Manufacturer: 10/02/2025
• Initial Report FDA Received Date: 09/09/2025
• Supplement Report FDA Received Date: 10/29/2025
• Was Device Evaluated by Manufacturer? (Y/N): No
• Date Device Manufactured: 07/05/2017
• 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: Hospitalization; Required Intervention
• Patient Age: 83 YR
• Patient Sex: Female
• Patient Weight: 90 KG
• Patient Ethnicity: Non Hispanic
• Patient Race: White