MAUDE Adverse Event Report: MEDACTA INTERNATIONAL SA GMK-SPHERE TIBIAL INSERT FIXED SPHERE FLEX SIZE 4/12 MM R; KNEE TIBIAL INSERT

Model Number	02.12.0412FR
Medical Device Problem Code	Break (1069)
Health Effect - Clinical Code	Pain (1994)
Date of Event	06/09/2022
Type of Reportable Event	Serious Injury
Event or Problem Description
Gmk sphere implanted approximately 6 years and 10 months ago (12 aug 2015) for osteoarthritis.The patient presented with a painful knee, and radiographs revealed that the insert screw had broken and was loose in the joint.The surgeon removed the part of the screw loose in the joint and implanted a new insert (without the screw).Only half of the screw was recovered, the other half is still lodged in the tibial tray.
Additional Manufacturer Narrative
Clinical evaluation performed by medacta medical affairs director: 6 years after primary cemented tka, the insert fixation screw is found broken and loose in the joint.Reoperation is undertaken to remove the screw and exchange the tibial insert.We cannot tell when the screw got loose.The surgeon assessed that the femoral component was not scratched and therefore there was no need to exchange it.The screw could have broken at surgery and then have remained in its seating for years, or it could have broken only very recently.According to report, no torque-limiting screwdriver was used: this may result in insufficient torque being applied (which could lead to self-unscrewing) or excessive torque that might break the screw.With the available information, we cannot tell what the root cause of this adverse event might have been.Visual inspection (only a part of the fixation screw received) performed by medacta knee r&d project manager: removal of broken fixation screw after 6 years and 10 months from primary implantation due to fixation screw breakage and consequent loosening.Reoperation is undertaken to remove the screw and exchange the tibial insert.The surgeon assessed that the femoral and tibial components were not scratched; therefore, they have not been replaced.The inlay screw broke in its threaded shaft, at the level of the cantilevered portion of the screw when fixed in the baseplate.The cause for screw breakage and when it occurred remains unknown, we can only suppose that it can be related to not correct tightening torque.We have no evidence that, at the time of the primary surgery, the torque limiting screwdriver (ref.02.07.10.4577; torque limiter screwdriver 3.5 nm) was used.This may result in insufficient torque being applied (which could lead to self-unscrewing) or excessive torque that might break the screw.Based on the available information is not possible to assert that the cause of failure is related to a faulty device.
Additional Manufacturer Narrative
On 11 nov 2022, we were informed that the insert was not revised, only the broken part of the screw loosened in the joint was removed.

• Brand Name: GMK-SPHERE TIBIAL INSERT FIXED SPHERE FLEX SIZE 4/12 MM R
• Common Device Name: KNEE TIBIAL INSERT
• Manufacturer (Section D): MEDACTA INTERNATIONAL SA; strada regina; castel san pietro, switzerland 6874 ; SZ 6874
• Manufacturer (Section G): MEDACTA INTERNATIONAL SA; strada regina; castel san pietro, switzerland 6874 ; SZ 6874
• Manufacturer Contact: stefano baj ; strada regina; castel san pietro, switzerland 6874 ; SZ 6874
• MDR Report Key: 15392133
• Report Number: 3005180920-2022-00679
• Device Sequence Number: 12057926
• Product Code: JWH
• UDI-Device Identifier: 07630030826580
• UDI-Public: 07630030826580
• Combination Product (Y/N): N
• Initial Reporter Country: SF
• PMA/510(K) Number: K121416
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Device Implanted Year: 2015
• Device Explanted Year: 2022
• Serviced by Third Party (Y/N): Unknown
• Reporter Type: Manufacturer
• Report Source: Distributor
• Initial Reporter Occupation: Non-Healthcare Professional
• Type of Report: Initial,Followup
• Report Date (Section B): 11/24/2022

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: 02.12.0412FR
• Device Catalogue Number: 02.12.0412FR
• Was Device Available for Evaluation?: Device Returned to Manufacturer
• Date Returned to Manufacturer: 09/06/2022
• Type of Report(Section G): Thirty-Day
• Initial Date Received by Manufacturer: 08/11/2022
• Supplement Date Received by Manufacturer: 08/11/2022
• Initial Report FDA Received Date: 09/09/2022
• Supplement Report FDA Received Date: 11/24/2022
• Was Device Evaluated by Manufacturer? (Y/N): Yes
• 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
• Patient Age: 71 YR
• Patient Sex: Female
• Patient Weight: 80 KG