MAUDE Adverse Event Report: SMITH & NEPHEW, INC. LEGION PS OXIN FEM SZ6 LT; PROSTHESIS, KNEE, PATELLOFEMOROTIBIAL, SEMI-CONSTRAINED, CEMENTED,

Model Number	71421216
Medical Device Problem Code	Adverse Event Without Identified Device or Use Problem (2993)
Health Effect - Clinical Codes	Joint Dislocation (2374); Metal Related Pathology (4530)
Date of Event	05/08/2020
Type of Reportable Event	Serious Injury
Additional Manufacturer Narrative
Internal reference number (b)(4).
Event or Problem Description
*us legal* it was reported that a patient has had recurrent disassociation of the xlpe liner from tibial component, in a legion tka.Second revision surgery was performed on (b)(6) 2020.The femoral component, tibial baseplate and poly insert were explanted.The patellar component was left in place.Upon revision, it was noticed that the inner synovium was stained black from metallosis.The poly component was found disengaged and subluxed.The femoral component was found worn from where it was engaging against the tibial component.The first revision surgery was performed on (b)(6) 2019 and is covered under (b)(4).
Additional Manufacturer Narrative
The associated device, used in treatment, was returned and evaluated.The lab analysis concluded that bone cement and bone was were present on the fixation surface of the femoral component and the tibial base.Apparent wear and scratches were observed on the superior surface of the tibial base polished surface and around the rail of the dovetail locking mechanism.Apparent wear and scratches were also observed on the articulating surface of the femoral component.The anterior aspect of the femoral component had wear and scratches, but the majority of the observed damage was concentrated on the posterior/distal aspect of the medial and lateral condyles.Some discoloration, damage, and deformation were observed on the articular surface of the tibial insert, but the majority of the damage to the tibial insert was noted on the inferior surface that interfaces with the tibial base.There was wear and deformation noted on the inferior surface of the insert that appears to match the shape/location of the rail of the locking mechanism of the tibial base.This wear and damage indicates that the insert spent some time in-vivo not engaged correctly with the dovetail locking mechanism, which his consistent with the reported complaint.No material or manufacturing deviations were identified during this investigation.The clinical/medical concluded that the root cause of the first revision was the anteriorly displaced insert secondary to a traumatic fall per documentation (case-2021-00067456).Based on the surgeon report of ¿more of a subacute problem¿ with radiological findings of cement anterior of the baseplate with heterotopic ossification and the intra-op finding of gross metallic staining of the surrounding soft tissues with severe wear of the femoral component (most likely from metal-on-metal articulation), along with the lab retrieval analysis conclusion that the insert wear/damage appears to match the shape/location of the rail of the baseplate locking mechanism and ¿indicates that the insert spent some time in-vivo not engaged correctly with the dovetail locking mechanism¿, it is unknown how long the patient actually ambulated with the disassociated component.The definitive root cause of the insert disassociation could not be concluded; however, the severity of the femoral and insert component wear and metal-stained tissues suggests a much longer duration that the 1 ½ weeks since the reported blunt-force-impact to the posterior knee (case-2020-00002563).The patient impact beyond the reported joint laxity, disassociation, pain, subsequent revisions, and noted metallic tissue staining during the 2nd revision could not be determined.No further medical assessment could be rendered at this time.Should additional clinical documentation become available in the future, the clinical/medical task may be re-evaluated.A review of complaint history did not reveal additional complaints for the listed batch.A review of the manufacturing records did not reveal a manufacturing abnormality that could have caused or contributed to the reported incident.At this time, we do not have reason to suspect that the product failed to meet any product specifications at the time of manufacture.A review of the risk management file and instructions for use documents revealed this failure mode and potential harm was previously identified.Possible causes could include but not limited to traumatic injury, surgical technique or size of device.Based on this investigation, the need for corrective action is not indicated.Should additional information be received, the complaint will be reopened.No further investigation is warranted for this complaint; however, we will continue to monitor future complaints and investigate as necessary.We consider this investigation closed.

• Brand Name: LEGION PS OXIN FEM SZ6 LT
• Common Device Name: PROSTHESIS, KNEE, PATELLOFEMOROTIBIAL, SEMI-CONSTRAINED, CEMENTED,
• Manufacturer (Section D): SMITH & NEPHEW, INC.; brooks rd. 1450; memphis TN 38116
• MDR Report Key: 12387847
• Report Number: 1020279-2021-06595
• Device Sequence Number: 14354943
• Product Code: JWH
• UDI-Device Identifier: 00885556030059
• UDI-Public: 00885556030059
• Combination Product (Y/N): N
• Initial Reporter Country: US
• PMA/510(K) Number: K043440
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Device Implanted Year: 2018
• Device Explanted Year: 2020
• Serviced by Third Party (Y/N): N
• Reporter Type: Manufacturer
• Report Source: company representative
• Initial Reporter Occupation: Other
• Type of Report: Initial,Followup
• Report Date (Section B): 10/21/2021

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?: Yes
• Operator of Device: Health Professional
• Device Model Number: 71421216
• Device Catalogue Number: 71421216
• Device Lot Number: 18CM09556
• Was Device Available for Evaluation?: Device Returned to Manufacturer
• Date Returned to Manufacturer: 09/23/2021
• Initial Date Received by Manufacturer: 01/12/2021
• Supplement Date Received by Manufacturer: 10/21/2021
• Initial Report FDA Received Date: 08/30/2021
• Supplement Report FDA Received Date: 10/21/2021
• Is This a Single-Use Device that was Reprocessed and Reused on a Patient? (Y/N): No
• Patient Sequence Number: 1
• Concomitant Medical Products and Therapy/Usage Dates: GII OVAL RESURFACING PAT 29MM/17KM02191
• Outcome Attributed to Adverse Event: Required Intervention
• Patient Age: 62 YR