MAUDE Adverse Event Report: STRYKER GMBH LOCKING SCREW VARIAX 2 T10, FULL THREAD, 3.5MM / L10MM; SCREW, FIXATION, BONE

Model Number	657310S
Medical Device Problem Code	Positioning Failure (1158)
Health Effect - Clinical Code	No Clinical Signs, Symptoms or Conditions (4582)
Date of Event	12/10/2021
Type of Reportable Event	Malfunction
Event or Problem Description
It was reported that intraoperatively, the locking did not lock, so it was replaced with a new screw.
Additional Manufacturer Narrative
Upon completion of investigation, additional information will be provided in a supplemental report.
Event or Problem Description
It was reported that intraoperatively, the locking did not lock, so it was replaced with a new screw.
Additional Manufacturer Narrative
The reported event could be confirmed, since the locking thread is damaged.The returned locking screw was inspected under a microscope.The thread below the screw head which is intended to lock the screw in the plate, shows plastic deformation which could explain the loss of the angular locking ability.The damage pattern suggests high force application during locking attempts.A potential non-conformity report was initiated to address this event.The comprehensive root cause analysis of the potential ncr included a surface and microstructure analysis as well as nano-indent hardness measurement of variax1 and variax2 screw samples by the fraunhofer institute on behalf of stryker.Further internal investigation efforts were focusing on the anodization color difference between variax1 and variax2 screws.Significant differences between the screws which could result in the reported complaints have not been revealed in either fraunhofer or stryker investigations.Excessive in-house handling and bench testing with variax2 screws from various manufacturing batches showed that locking is achieved as intended.The desired increase in torque indicating to the customer that the screw is locking in the plate, can be confirmed.A review of the device history for the reported lot did not indicate any abnormalities.No deviation from the specifications was noted.No indications of material, manufacturing or design related problems were found during the investigation.

• Brand Name: LOCKING SCREW VARIAX 2 T10, FULL THREAD, 3.5MM / L10MM
• 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: sharon rivas ; 325 corporate drive; mahwah, NJ 07430 ; 2018315000
• MDR Report Key: 13158084
• Report Number: 0008031020-2022-00004
• Device Sequence Number: 14447709
• Product Code: HWC
• UDI-Device Identifier: 07613327086799
• UDI-Public: 07613327086799
• Combination Product (Y/N): N
• Initial Reporter Country: JA
• PMA/510(K) Number: K132502
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Reporter Type: Manufacturer
• Report Source: Health Professional
• Initial Reporter Occupation: Physician
• Type of Report: Initial,Followup
• Report Date (Section B): 02/16/2022

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Is this an Adverse Event Report?: No
• Is this a Product Problem Report?: Yes
• Operator of Device: Health Professional
• Device Expiration Date: 07/31/2025
• Device Model Number: 657310S
• Device Catalogue Number: 657310S
• Device Lot Number: G31133
• Was Device Available for Evaluation?: Device Returned to Manufacturer
• Date Returned to Manufacturer: 12/28/2021
• Is the Reporter a Health Professional?: Yes
• Type of Report(Section G): Follow-Up
• Initial Date Received by Manufacturer: 12/10/2021
• Supplement Date Received by Manufacturer: 01/19/2022
• Initial Report FDA Received Date: 01/04/2022
• Supplement Report FDA Received Date: 02/16/2022
• Was Device Evaluated by Manufacturer? (Y/N): Yes
• Date Device Manufactured: 08/25/2020
• 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
• Patient Age: 56 YR
• Patient Sex: Female
• Patient Weight: 52 KG