MAUDE Adverse Event Report: STRYKER ORTHOPAEDICS-MAHWAH MRH KNEE FEM S RGT; PROSTHESIS, KNEE, FEMOROTIBIAL, CONSTRAINED, CEMENTED, METAL/POLYMER

Model Number	6481-1-111
Medical Device Problem Code	Fracture (1260)
Health Effect - Clinical Codes	Ambulation or Postural Difficulties (2544); Insufficient Information (4580)
Date of Event	03/15/2021
Type of Reportable Event	Serious Injury
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.Device not returned.
Event or Problem Description
Patient had mrh knee implanted.The stem / femur interface appeared damaged.Femoral component revised to gmrs distal femur.Spoke to rep.Rep confirmed that there are no allegations against the revised augments and that no further information will be released by the hospital or surgeon.
Additional Manufacturer Narrative
Reported event: an event regarding crack/fracture involving a mrh femoral component was reported.The event was confirmed via clinician review.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 information by a clinical consultant indicated: undated/unlabeled lateral knee x-ray: cemented hinge with broken stem implant interface.Undated lateral right x-ray x2, stemmed cemented hinge with broken stem implant interface of femur undated ap right x-ray, cement hinge, possible loosening of femur with significant bone loss distally (fixation all at cemented stem) undated implant sheet: implant date of stemmed hinge with tibial cone, bone grafting.Event confirmation: the event was confirmed, there was damage to the femoral stem-implant interface with apparent fracture.Root cause: the root cause cannot be determined without additional information in the form of medical and radiographic records, additional activity history or history of trauma, and if possible, the explants.I suspect that based on the provided x-rays the bending loads at the interface with the stem well fixed and the femoral implant unsupported, resulted in fatigue fracture of the metal interface.Product history review: could not be performed as the device lot details were not provided.Complaint history review: could not be performed as the device lot details were not provided.Conclusions: it was reported that the patient's knee was revised as the stem and femur device interface appeared damaged.Clinician review of provided medical records confirmed the reported event; there was damage to the femoral stem-implant interface with apparent fracture.However, it's not clear how the interface is damaged.The exact cause of the event could not be determined because insufficient information was provided.Further information such as return of the device, pathology reports, additional activity history or history of trauma, pre- and post-operative x-rays and the primary operative report as well as patient history and follow-up notes are needed to complete the investigation for determining root cause.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.
Event or Problem Description
Patient had mrh knee implanted.The stem/femur interface appeared damaged.Femoral component revised to gmrs distal femur.Spoke to rep.Rep confirmed that there are no allegations against the revised augments and that no further information will be released by the hospital or surgeon.

• Brand Name: MRH KNEE FEM S RGT
• Common Device Name: PROSTHESIS, KNEE, FEMOROTIBIAL, CONSTRAINED, CEMENTED, METAL/POLYMER
• Manufacturer (Section D): STRYKER ORTHOPAEDICS-MAHWAH; 325 corporate drive; mahwah NJ 07430
• MDR Report Key: 11634193
• Report Number: 0002249697-2021-00645
• Device Sequence Number: 3397359
• Product Code: KRO
• UDI-Device Identifier: 07613327045147
• UDI-Public: 07613327045147
• Combination Product (Y/N): N
• Initial Reporter State: NY
• Initial Reporter Country: US
• PMA/510(K) Number: K002552
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Device Implanted Year: 2018
• Device Explanted Year: 2021
• Reporter Type: Manufacturer
• Report Source: health professional
• Initial Reporter Occupation: Physician
• Type of Report: Initial,Followup
• Report Date (Section B): 05/21/2021

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: 6481-1-111
• Device Catalogue Number: 64811111
• Device Lot Number: UNKNOWN
• Was Device Available for Evaluation?: No
• Initial Date Received by Manufacturer: 03/15/2021
• Supplement Date Received by Manufacturer: 04/28/2021
• Initial Report FDA Received Date: 04/08/2021
• Supplement Report FDA Received Date: 05/21/2021
• Is This a Single-Use Device that was Reprocessed and Reused on a Patient? (Y/N): No
• Patient Sequence Number: 1
• Outcome Attributed to Adverse Event: Hospitalization; Required Intervention
• Patient Age: 59 YR
• Patient Weight: 75