MAUDE Adverse Event Report: STRYKER ORTHOPAEDICS-MAHWAH X3 TRIATHLON CS INSERT #7 16MM; PROSTHESIS, KNEE, PATELLO/FEMOROTIBIAL, SEMI-CONSTRAINED, UNCEMENTED, POROUS, C

Catalog Number 5531G716

Device Problem Insufficient Information (3190)

Patient Problems Scar Tissue (2060); Injury (2348)

Event Date 06/08/2017

Event Type  Injury  

Manufacturer Narrative

It was noted that the device is not available for evaluation.Additional information has been requested and if received, will be provided in the supplemental report upon completion of the investigation.Review of the device history records indicates devices were manufactured and accepted into final stock with no reported discrepancies.There have been no other similar events for the lot referenced.

Event Description

The surgeon revised a total knee due to instability.He changed the tibial insert from a size 16 to a 19 cs.The patient originally had a mako uni knee done in 2011, then was revised to a total knee on (b)(6) 2016.

Manufacturer Narrative

An event regarding instability involving a triathlon insert was reported.The event was not confirmed.Device evaluation and results: not performed as no device was returned for evaluation.Medical records received and evaluation: revision of triathlon cs bearing due to instability some 1-year post implantation in a male patient of (b)(6) years ((b)(6)) with overweight (bmi = 32) and unknown activity level.The original 16-mm cs bearing was replaced with a 19-mm cs bearing.The original implantation in 2016, was already a revision of a mako unicondylar device implanted in 2011, and removed after infection due to a dental procedure.Knee flexion was somewhat limited with 110°.There is minimal clinical information although the indication for revision was provided as instability of the knee as also confirmed by the facts of revision surgery with exchange of the tibial bearing for a thicker one going from a 16-mm to 19-mm triathlon cs type bearing.Early after infection the knee may still be rather stiff due to soft tissue contracture as a consequence of the scar tissue formation related to the recent surgical procedures.This may cause difficulty with insertion of the tibial bearing during both trial testing and final assembly and may result in an adequate thickness of the bearing at time of implantation, the maximum achievable at the time that may however not be adequate on the longer term.With the pain relieved by the surgery, activity level will increase while residual effects of the previous infection gradually disappear and any prior contracture due to scar tissue formation then may resolve and may render the knee unstable.If a thicker bearing had been implanted at time of previous revision, the knee would have become too stiff which is also not recommendable.So, all-in-all difficult choices where the optimum is not always achievable in one surgery and repeat interventions may be required to gradually approach the patient¿s optimum bearing thickness.Device 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 reported lot referenced.Conclusions: the medical review indicated that -multiple failed knee arthroplasty including prior infection has contributed to excessive scar tissue formation in and around the knee that limited optimal bearing thickness implantation at time of reconstruction after infection treatment.Gradual relaxation of scar tissue resulted in mild instability requiring bearing exchange to a 3-mm thicker cs type bearing.The exact cause of the event could not be determined because insufficient information was provided.Further information such as product return, pre- and post-operative x-rays, operative reports as well as patient history and follow-up notes are needed to complete the investigation for determining a root cause.A capa trend analysis was conducted for the reported failure mode and concluded instability may result from other factors not necessarily related to the device.No further investigation is possible at this time.If additional information becomes available to indicate further evaluation is warranted, this record will be reopened.

Event Description

The surgeon revised a total knee due to instability.He changed the tibial insert from a size 16 to a 19 cs.The patient originally had a mako uni knee done in 2011, then was revised to a total knee on (b)(6) 2016.

• Brand Name: X3 TRIATHLON CS INSERT #7 16MM
• Type of Device: PROSTHESIS, KNEE, PATELLO/FEMOROTIBIAL, SEMI-CONSTRAINED, UNCEMENTED, POROUS, C
• Manufacturer (Section D): STRYKER ORTHOPAEDICS-MAHWAH; 325 corporate drive; mahwah NJ 07430
• Manufacturer (Section G): STRYKER ORTHOPAEDICS-LIMERICK; raheen business park; limerick NA
• Manufacturer Contact: brian lauro ; 325 corporate drive; mahwah, NJ 07430 ; 2018315000
• MDR Report Key: 6691907
• MDR Text Key: 79228027
• Report Number: 0002249697-2017-02118
• Device Sequence Number: 1
• Product Code: MBH
• Combination Product (y/n): N
• Reporter Country Code: US
• PMA/PMN Number: K141056
• Number of Events Reported: 1
• Summary Report (Y/N): N
• Report Source: Manufacturer
• Source Type: health professional,other
• Reporter Occupation: Physician
• Type of Report: Initial,Followup
• Report Date: 09/21/2017

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Date FDA Received: 07/06/2017
• Is this an Adverse Event Report?: Yes
• Is this a Product Problem Report?: No
• Device Operator: Health Professional
• Device Expiration Date: 09/12/2019
• Device Catalogue Number: 5531G716
• Device Lot Number: LDZ338
• Was Device Available for Evaluation?: No
• Is the Reporter a Health Professional?: Yes
• Date Manufacturer Received: 08/25/2017
• Was Device Evaluated by Manufacturer?: Device Not Returned to Manufacturer
• Date Device Manufactured: 09/12/2014
• Is the Device Single Use?: Yes
• Is This a Reprocessed and Reused Single-Use Device?: No
• Type of Device Usage: Initial
• Patient Sequence Number: 1
• Patient Outcome(s): Hospitalization; Required Intervention
• Patient Age: 56 YR
• Patient Weight: 94