MAUDE Adverse Event Report: STRYKER GMBH LOCKING SCREW VARIAX 2 T10, FULL THREAD, 3.5MM / L18MM; SCREW, FIXATION, BONE

Model Number	657318S
Medical Device Problem Codes	Device Dislodged or Dislocated (2923); Migration (4003)
Health Effect - Clinical Code	Insufficient Information (4580)
Date of Event	04/07/2022
Type of Reportable Event	Serious Injury
Event or Problem Description
It was reported that there was screw loosening and poor fixation was discovered.Therefore, all the implants were extracted.
Additional Manufacturer Narrative
Once the investigation has been completed any additional information will be reported in a supplemental report.
Additional Manufacturer Narrative
The reported event could not be confirmed, since the returned device is conforming to specifications and is fully functional.In addition was no other evidence, like x-rays that would confirm the loosening of all screws, provided.The device inspection revealed the following: the visual inspection has shown that locking threads of all four locking screws are in a good condition, as with the plate is just very minor damage from screw locking visible.Only at the lower thread flank of the locking threads are slight wear marks visible.Based on that and the condition of the plate holes an over-tightening of the screws can be excluded.But on the other side it can also not be confirmed if the screws were sufficiently tightened during insertion.A functional test with the also received four locking screw was performed, all locking screws can be locked in the locking holes of the plate without any issue.Due the nature of the bone screws a locking of these devices is not possible, but the received screw do fit into the oblong hole of the plate without any issues.All in all no functional issue with the returned devices could be detected.A review of the device history for the reported lot did not indicate any abnormalities.No corrective actions are required at this time.A review of the labeling did not indicate any abnormalities.No indications of material, manufacturing or design related problems were found during the investigation.Based on investigation, the root cause was attributed to a patient related issue.The failure that the screws did get loose after they were for almost one year implanted was most likely caused by the reported activity level and behavior of patient, where the surgeon said that the patient was highly active and may have been working too hard.However, it can also not be excluded that insufficient tightening of the screw did contribute to the loosening of the screw as the received devices show in the screw interface regions less damage than expected after a screw was driven in.If more information is provided, the case will be reassessed.
Event or Problem Description
It was reported that there was screw loosening and poor fixation was discovered.Therefore, all the implants were extracted.

• Brand Name: LOCKING SCREW VARIAX 2 T10, FULL THREAD, 3.5MM / L18MM
• Common Device Name: SCREW, FIXATION, BONE
• Manufacturer (Section D): STRYKER GMBH; bohnackerweg 1; postfach; selzach 2545 ; SZ 2545
• Manufacturer (Section G): STRYKER GMBH; bohnackerweg 1; postfach; selzach 2545 ; SZ 2545
• Manufacturer Contact: anna jusinski ; 325 corporate drive; mahwah, NJ 07430 ; 2018315000
• MDR Report Key: 14251331
• Report Number: 0008031020-2022-00219
• Device Sequence Number: 19909114
• Product Code: HWC
• UDI-Device Identifier: 07613327086904
• UDI-Public: 07613327086904
• Combination Product (Y/N): N
• Initial Reporter Country: JA
• PMA/510(K) Number: K132502
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Device Implanted Year: 2021
• Device Explanted Year: 2022
• Reporter Type: Manufacturer
• Report Source: Health Professional
• Initial Reporter Occupation: Physician
• Type of Report: Initial,Followup
• Report Date (Section B): 07/26/2022

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
• Operator of Device: Lay User/Patient
• Device Expiration Date: 10/31/2024
• Device Model Number: 657318S
• Device Catalogue Number: 657318S
• Device Lot Number: D54226
• Was Device Available for Evaluation?: Device Returned to Manufacturer
• Date Returned to Manufacturer: 04/21/2022
• Is the Reporter a Health Professional?: Yes
• Type of Report(Section G): Follow-Up
• Initial Date Received by Manufacturer: 04/07/2022
• Supplement Date Received by Manufacturer: 06/29/2022
• Initial Report FDA Received Date: 04/29/2022
• Supplement Report FDA Received Date: 07/26/2022
• Was Device Evaluated by Manufacturer? (Y/N): Yes
• Date Device Manufactured: 12/05/2019
• 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: 50 YR
• Patient Sex: Male
• Patient Weight: 60 KG