MAUDE Adverse Event Report: MEDACTA INTERNATIONAL SA GMK-SPHERE TIBIAL INSERT FIXED SPHERE FLEX SIZE 5/10 MM R; KNEE TIBIAL INSERT

Model Number 02.12.0510FR

Device Problem Device Slipped (1584)

Patient Problem Insufficient Information (4580)

Event Date 06/21/2022

Event Type  Injury  

Event Description

During a follow-up visit, it was noted from the xrays that the screw of the insert had come out.At 7 years and 3 months after the primary surgery, the revision surgery was performed and during the revision it was also noted that the tibial tray was loosened and that no cement was present on the implant.It is unknown if the surgeon used a torque-limiting screwdriver during the primary.

Manufacturer Narrative

Batch review performed on 22 june 2022: lot 141808: (b)(4) items manufactured and released on 22-may-2014.Expiration date: 2019-apr-30.No anomalies found related to the problem.To date, all items of the same lot have been sold with 1 similar reported event.Considering the lot of the screw - ref.75.16.291 lot.141657: lot 141657: (b)(4) items manufactured and 123 lots manufactured with this semifinished.8 out of 123 lots are involved in complaints for unscrewing: 10 complaints in total (2 lots are involved in 2 complaints).Additional device involved: batch review performed on 22 june 2022: gmk-sphere 02.07.1205r tibial tray fixed cemented size 5 r (k090988) lot 144874: (b)(4) items manufactured and released on 07-aug-2014.Expiration date: 2019-june-30.No anomalies found related to the problem.To date, all items of the same lot have been sold with no similar reported event.Clinical evaluation performed by medacta medical director: at about 7 years after primary cemented tka, the patient feels instability and the xray examination shows a dislodged insert fixation screw and probably a mobilized tibial tray.The screw is far away from articulating areas; there is no mention, in the report, of damages ascertained during revision surgery to the articulating surfaces of the femoral component.The report also mentions easy detachment of the tibial tray from the cement mantle: the clinical relevance of this finding is not determined in the report.Normally, this condition occurs when a cementation problem has occurred.7 years is an unusual time both for the self-unscrewing of the insert screw and for the metal debonding from cement.From preliminary investigation performed by medacta r&d knee manager: revision surgery of a gmk sphere implant after 7 years from primary implantation due to tibia loosening.Pre-revision x-rays showed that the tibial insert secure screw was loosened in the joint.The picture sent for investigation shows that the tibial components (tray and insert) have been removed and the cement remained adherent to the bone.Reasons for loosening are most likely related to cement and cementation problem and not to the implant.Loosening of the secure screw was probably caused by insufficient tightening torque applied to the screw at the time of primary implantation.A torque limiting screwdriver, not available at the time of the primary surgery, is currently available and mandatory to lock the secure screw.From preliminary investigation, there is no evidence that the event is related to an implant failure.

Manufacturer Narrative

Visual inspection performed by r&d project manager: revision surgery of a gmk sphere implant after 7 years from primary implantation due to tibia loosening and fixation screw loosening.On the articular surface of the tibial insert, it is possible to note deep scratches on both the lateral side and central area.These signs are compatible with the fixation screw, which, once become loose, it is possible to suppose that it has been positioned in the joint space and may have generated those grooves and scratches.The most likely cause for self-unscrewing of the screw is insufficient tightening torque.A torque limiting screwdriver, not available at the time of the primary surgery, is currently available and mandatory to lock the secure screw.No cement is present on the bottom surface of the explanted tibial tray.Poor interdigitation between cement and implant can be related to multiple factors, most likely not implant related (such as cementation process, temperature, time, and presence of fluids on the surfaces of cement interface).The lack of cement adhering to the device is not evidence of a faulty device.No other elements relevant to the event can be noted from visual inspection.

• Brand Name: GMK-SPHERE TIBIAL INSERT FIXED SPHERE FLEX SIZE 5/10 MM R
• Type of Device: KNEE TIBIAL INSERT
• Manufacturer (Section D): MEDACTA INTERNATIONAL SA; strada regina; castel san pietro, 6874 ; SZ 6874
• Manufacturer (Section G): MEDACTA INTERNATIONAL SA; strada regina; castel san pietro, 6874 ; SZ 6874
• Manufacturer Contact: stefano baj ; strada regina; castel san pietro, switzerland 6874 ; SZ 6874
• MDR Report Key: 15064777
• MDR Text Key: 296222258
• Report Number: 3005180920-2022-00532
• Device Sequence Number: 1
• Product Code: JWH
• UDI-Device Identifier: 07630030826740
• UDI-Public: 07630030826740
• Combination Product (y/n): N
• Reporter Country Code: UK
• PMA/PMN Number: K121416
• Number of Events Reported: 1
• Summary Report (Y/N): N
• Report Source: Manufacturer
• Source Type: Company Representative
• Reporter Occupation: Non-Healthcare Professional
• Type of Report: Initial,Followup
• Report Date: 08/24/2022

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?: No
• Device Operator: Health Professional
• Device Expiration Date: 04/30/2019
• Device Model Number: 02.12.0510FR
• Device Catalogue Number: 02.12.0510FR
• Device Lot Number: 141808
• Was Device Available for Evaluation?: Device Returned to Manufacturer
• Initial Date Manufacturer Received: 06/21/2022
• Initial Date FDA Received: 07/20/2022
• Supplement Dates Manufacturer Received: 06/21/2022
• Supplement Dates FDA Received: 08/24/2022
• Was Device Evaluated by Manufacturer?: Yes
• Date Device Manufactured: 05/22/2014
• 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): Required Intervention
• Patient Age: 63 YR
• Patient Sex: Male
• Patient Weight: 111 KG
• Patient Ethnicity: Non Hispanic
• Patient Race: White