MAUDE Adverse Event Report: STRYKER GMBH BONE SCREW VARIAX2 T10, FULL THREAD, 3.5MM / L50MM; PLATE, FIXATION, BONE

Model Number	657450S
Medical Device Problem Code	Material Fragmentation (1261)
Health Effect - Clinical Codes	No Known Impact Or Consequence To Patient (2692); No Clinical Signs, Symptoms or Conditions (4582)
Date of Event	08/13/2020
Type of Reportable Event	Malfunction
Additional Manufacturer Narrative
Upon completion of investigation, additional information will be provided in a supplemental report.
Event or Problem Description
The customer reported that during the case the screw thread on 3 screws appears to have stripped off in places.
Event or Problem Description
The customer reported that during the case the screw thread on 3 screws appears to have stripped off in places.
Additional Manufacturer Narrative
Correction: d4, lot# conclusion: the reported event could be confirmed since the device was returned for evaluation and matches the alleged failure.The device inspection revealed the following: the received screw was found to be having damaged threads around the middle moving towards proximal, covering approximately 6-8 threads.A metal splinter/wire was also formed which is most likely to have emerged from one of the middle threads and continued to form as the screw was pushed inside.The wire and the thread surface were found to be flat and plastically deformed.These damages and wire formation indicates towards excessive force that was applied to screw in the screw with some misalignment/angulation with the plate, leading to strip-off.A review of the device history for the reported lot did not indicate any abnormalities.No corrective actions are required at this time.No indications of manufacturing or design related problems were found during the investigation.A review of the labeling did not indicate any abnormalities.Based on the above investigation, the root cause of the failure is determined to be user related.There was a definite overtightening and misalignment of the screw involved as observed through the manner of deformation and stripping in the returned screw.The operative technique clearly provides a caution in inserting bone screws: ¿note: during bone screw insertion in an oblong hole, the surgeon should rely on tactile feedback to prevent excessive torque which may result in thread / bone stripping, screw damage / pull through, or screwdriver damage.Proper observation of bone quality, screw size, and instrumentation can help determine the appropriate insertion torque during insertion and final tightening of the screw in the plate.When the screw is fully seated during final tightening, an increase of resistance indicates sufficient screw fixation.¿ if any additional information is provided, the investigation will be reassessed.

• Brand Name: BONE SCREW VARIAX2 T10, FULL THREAD, 3.5MM / L50MM
• Common Device Name: PLATE, FIXATION, BONE
• Manufacturer (Section D): STRYKER GMBH; bohnackerweg 1; postfach; selzach 2545 ; SZ 2545
• MDR Report Key: 10485322
• Report Number: 0008031020-2020-02207
• Device Sequence Number: 11439895
• Product Code: HRS
• UDI-Device Identifier: 07613327074277
• UDI-Public: 07613327074277
• Combination Product (Y/N): N
• Initial Reporter Country: GB
• 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: Other Health Care Professional
• Type of Report: Initial,Followup
• Report Date (Section B): 11/11/2020

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: 09/30/2023
• Device Model Number: 657450S
• Device Catalogue Number: 657450S
• Device Lot Number: Y30613
• Was Device Available for Evaluation?: Device Returned to Manufacturer
• Date Returned to Manufacturer: 09/29/2020
• Initial Date Received by Manufacturer: 08/13/2020
• Supplement Date Received by Manufacturer: 10/15/2020
• Initial Report FDA Received Date: 09/02/2020
• Supplement Report FDA Received Date: 11/11/2020
• Is This a Single-Use Device that was Reprocessed and Reused on a Patient? (Y/N): No
• Patient Sequence Number: 1