MAUDE Adverse Event Report: SMITH & NEPHEW, INC. GNS II BICONVEX PAT 29MM; PROSTHESIS, KNEE, PATELLOFEMOROTIBIAL, SEMI-CONSTRAINED, CEMENTED, POLYMER/METAL

Catalog Number	71420570
Medical Device Problem Code	Loosening of Implant Not Related to Bone-Ingrowth (4002)
Health Effect - Clinical Code	Implant Pain (4561)
Date of Event	02/06/2025
Type of Reportable Event	Serious Injury
Event or Problem Description
It was reported that, after a left tka surgery that had been performed on (b)(6) 2022, the patient experienced pain in the patella.This adverse event was addressed by a revision surgery on (b)(6) 2025.Upon opening the knee, it was reportedly obvious that the patella button had loosened as it was loose in the joint.Upon inspection, it looked like the cement did not adhere to the very sclerotic bone of the native patella.The patella was cut flat, and a gen ii oval patella was placed on.The current health status of the patient is unknown.
Additional Manufacturer Narrative
Internal complaint reference: (b)(4).This complaint was opened by smith+nephew to document a patient complication related to a product problem with a smith+nephew device.The reported issue(s) relate to known inherent device and/or procedural risks that are appropriately documented in our risk files.Smith+nephew will continue to monitor trends in accordance with our post-market surveillance process and take necessary action as required if anticipated severity and/or occurrence rates are exceeded.Smith+nephew has no reason to suspect that the product failed to meet any specifications at the time of manufacture.Based on our review of all currently available information, we are unable to identify a definitive root cause.However, as the use of our product cannot be excluded as a potential cause or contributory factor to the reported issue, we are conservatively submitting this report in accordance with applicable regulations.If additional information becomes available that alters the conclusions of this report, a follow-up report will be submitted as required.
Additional Manufacturer Narrative
H3, h6: the device was not returned for evaluation; therefore, a device analysis could not be performed.The photographs were reviewed, and did not reveal any defects.The clinical/medical investigation concluded that the likely definitive clinical root cause of the reported pain is the loosening patella resulting from the sclerotic bone of the native patella or poor cementation which may be technique related.Therefore, the impact to the patient beyond the reported pain, subsequent revision, and the expected convalescence period could not be determined since the patient¿s outcome was not reported.Device batch number was not provided, thus, an evaluation of the manufacturing records could not be performed.A review of complaint history for the previous 12 months did not reveal similar events for the listed device.A review of the instructions for use documents for knee systems revealed that looseness of components has been identified in possible adverse effects section as a result from trauma, improper implant selection, improper implant positioning, improper fixation, and/or migration of the components.Muscle and fibrous tissue laxity can also contribute to these conditions.A review of the risk management file revealed this failure mode was previously identified.The anticipated risk level is still adequate.A historical review concluded that there are no prior actions related to this product and event.At this time, we have no evidence to conclude that the product failed to meet any specifications at the time of manufacture.Factors that could contribute to the reported event include abnormal motion over time, bone degeneration, inadequate integration between the cement and bone/implant, osteolysis and/or injury.Based on this investigation, the need for corrective action is not indicated.Should the device or additional information be received, the complaint will be reopened.No further investigation is warranted for this complaint; however, we will continue to monitor for future complaints and investigate as necessary.We consider this investigation closed.

• Brand Name: GNS II BICONVEX PAT 29MM
• Common Device Name: PROSTHESIS, KNEE, PATELLOFEMOROTIBIAL, SEMI-CONSTRAINED, CEMENTED, POLYMER/METAL
• Manufacturer (Section D): SMITH & NEPHEW, INC.; 1450 brooks rd.; memphis TN 38116
• Manufacturer (Section G): SMITH & NEPHEW, INC.; 1450 brooks rd.; memphis TN 38116
• Manufacturer Contact: holly topping ; 7000 west william cannon drive; austin, TX 78735 ; 5123913905
• MDR Report Key: 21434374
• Report Number: 1020279-2025-00313
• Device Sequence Number: 17227639
• Product Code: JWH
• UDI-Device Identifier: 03596010208279
• UDI-Public: 3596010208279
• Combination Product (Y/N): N
• Initial Reporter Country: AS
• PMA/510(K) Number: K951987
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Device Implanted Year: 2022
• Device Explanted Year: 2025
• Serviced by Third Party (Y/N): N
• Reporter Type: Manufacturer
• Report Source: Other,Foreign,Health Professional,Company Representative
• Initial Reporter Occupation: Physician
• Type of Report: Initial,Followup
• Report Date (Section B): 04/24/2025

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?: Yes
• Operator of Device: Health Professional
• Device Catalogue Number: 71420570
• Device Lot Number: UNKNOWN
• Was Device Available for Evaluation?: No
• Is the Reporter a Health Professional?: Yes
• Type of Report(Section G): Thirty-Day
• Initial Date Received by Manufacturer: 02/06/2025
• Supplement Date Received by Manufacturer: 04/21/2025
• Initial Report FDA Received Date: 02/21/2025
• Supplement Report FDA Received Date: 04/24/2025
• Was Device Evaluated by Manufacturer? (Y/N): No
• 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: Required Intervention; Hospitalization
• Patient Sex: Unknown