MAUDE Adverse Event Report: STRYKER ORTHOPAEDICS-MAHWAH TRIATHLON ASYMMETRIC X3 PATELLA; PROSTHESIS, KNEE, PATELLO/FEMOROTIBIAL, SEMI-CONSTRAINED, UNCEMENTED, POROUS, CO

Model Number 5551-G-381

Device Problems Fracture (1260); Mechanical Problem (1384); Loss of Osseointegration (2408)

Patient Problems Injury (2348); Ambulation Difficulties (2544); Inadequate Osseointegration (2646)

Event Date 07/09/2019

Event Type  Injury  

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.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.

Event Description

Procedure: the patient underwent right total knee replacement (b)(6) 2016.Patient had a lot of pain, radiographs revealed patella fracture with loosen component.Then patient underwent right total knee revision and patella was exchanged (b)(6) 2019.

Manufacturer Narrative

An event regarding loosening and subluxation involving a triathlon patella was reported.The event was confirmed through clinician review of the provided medical records.Method & results: product evaluation and results: not performed as no product was returned for evaluation.Clinician review: a review of the provided medical records and x-rays by a clinical consultant indicated: another ap, lateral and patellar view of the right knee is labeled ¿index surgery¿ and demonstrates a cemented right total knee arthroplasty.The knee is reduced and the patella is noted to have a lateral tilt.Another ap, lateral and patellar view of the right knee labeled ¿pre-revision¿ shows the tibia and femoral components unchanged with the patella subluxated laterally with a disassociated patellar component from the host patella.In this varus osteoarthritic knee with nominally tracking patella, post-operative index surgery x-rays noted lateral patellar tilt.This may have resulted from internal rotation of either or both femoral and tibial components resulting in shear forces on the patellar component, ultimately resulting in disassociation over three years in situ.Examination of the explanted component would confirm this mechanism and rule out factors of implant manufacturing or materials as having contributed to this clinical event.Product history review: indicated all devices were manufactured and accepted into final stock with no reported discrepancies.Complaint history review: there have been no other similar events for the lot referenced.Conclusion: the event itself was confirmed through clinician review of the provided medical records who indicated that the patellar component disassociated from the host patella with lateral subluxation of the host patella.The exact cause of the event could not be determined because insufficient information was provided.Further information such as clinical and past medical history as well as examination of the explanted components are required to complete the investigation for determining a root cause.No further investigation is required at this time.If additional information becomes available to indicate further evaluation is warranted, this record will be reopened.

Event Description

Procedure: the patient underwent right total knee replacement (b)(6) 2016.Patient had a lot of pain, radiographs revealed patella fracture with loosen component.Then patient underwent right total knee revision and patella was exchanged (b)(6) 2019.

• Brand Name: TRIATHLON ASYMMETRIC X3 PATELLA
• Type of Device: PROSTHESIS, KNEE, PATELLO/FEMOROTIBIAL, SEMI-CONSTRAINED, UNCEMENTED, POROUS, CO
• Manufacturer (Section D): STRYKER ORTHOPAEDICS-MAHWAH; 325 corporate drive; mahwah NJ 07430
• MDR Report Key: 9652531
• MDR Text Key: 177145581
• Report Number: 0002249697-2020-00198
• Device Sequence Number: 1
• Product Code: MBH
• UDI-Device Identifier: 07613327014822
• UDI-Public: 07613327014822
• Combination Product (y/n): N
• PMA/PMN Number: K141056
• Number of Events Reported: 1
• Summary Report (Y/N): N
• Report Source: Manufacturer
• Source Type: health professional
• Type of Report: Initial,Followup
• Report Date: 04/16/2020

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Date FDA Received: 01/31/2020
• Is this an Adverse Event Report?: Yes
• Is this a Product Problem Report?: No
• Device Operator: Health Professional
• Device Expiration Date: 04/30/2022
• Device Model Number: 5551-G-381
• Device Catalogue Number: 5551-G-381
• Device Lot Number: KNE4
• Was Device Available for Evaluation?: No
• Date Manufacturer Received: 03/19/2020
• Is This a Reprocessed and Reused Single-Use Device?: No
• Patient Sequence Number: 1
• Patient Outcome(s): Hospitalization; Required Intervention
• Patient Age: 52 YR
• Patient Weight: 127