MAUDE Adverse Event Report: STRYKER GMBH LOCKING SCREW,T8 FULL THREAD, 2.7MM/L20MM; SCREW, FIXATION, BONE

Catalog Number	656320S
Medical Device Problem Code	Positioning Failure (1158)
Health Effect - Clinical Code	No Clinical Signs, Symptoms or Conditions (4582)
Date of Event	07/03/2023
Type of Reportable Event	Malfunction
Additional Manufacturer Narrative
Once the investigation has been completed any additional information will be reported in a supplemental report.
Event or Problem Description
As reported: "three locking screws failed to lock during surgery for distal end of the left radius using variax dr.The locking screws did not lock onto the plate and spun without fastening.All three screws were replaced with new screws.After replacement, the plate could be locked using new screws.".
Additional Manufacturer Narrative
The reported event could be confirmed, since the device was returned and it matches the alleged issue.The device inspection revealed the following: in the received screw, the threads in the shaft portion were found to be relatively in good condition with no evident damage.However, a couple of locking threads underneath the head were found to be damaged with severe material erosion.The drive of the screw showed normal signs of usage with no abnormality found.A functional test was performed by assembling the returned screw with a sample variax plate.Upon testing it could be confirmed that the screw were indeed not able to lock to the plate due to the obvious thread damage.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.Based on the above investigation, the root cause of the issue is deemed to be user related.The nature of deformation underneath the head of the screw and the fact that the rest of the threads of the screw were undamaged, indicate that the screw got inserted easily but was eventually rotated more than required, under application of high axial force.The ifu clearly instructs the user that: ¿screws should not be over-tightened during insertion.Excessive over-tightening will compromise the integrity of the screw head, result in possible screw breakage, and lead to loss of friction fit performance.¿ if any further information is provided, the complaint report will be updated.
Event or Problem Description
As reported: "three locking screws failed to lock during surgery for distal end of the left radius using variax dr.The locking screws did not lock onto the plate and spun without fastening.All three screws were replaced with new screws.After replacement, the plate could be locked using new screws.".

• Brand Name: LOCKING SCREW,T8 FULL THREAD, 2.7MM/L20MM
• Common Device Name: SCREW, FIXATION, BONE
• Manufacturer (Section D): STRYKER GMBH; bohnackerweg 1; postfach; selzach 2545 ; SZ 2545
• Manufacturer (Section G): STRYKER LEIBINGER FREIBURG; boetzingerstr. 41; freiburg D-791 11; GM D-79111
• Manufacturer Contact: anna jusinski ; 325 corporate drive; mahwah, NJ 07430 ; 2018315000
• MDR Report Key: 17414075
• Report Number: 0008031020-2023-00282
• Device Sequence Number: 15679136
• Product Code: HWC
• UDI-Device Identifier: 07613327070712
• UDI-Public: 07613327070712
• Combination Product (Y/N): N
• Initial Reporter Country: JA
• PMA/510(K) Number: K180500
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Reporter Type: Manufacturer
• Report Source: Other
• Initial Reporter Occupation: Other
• Type of Report: Initial,Followup
• Report Date (Section B): 10/02/2023

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 Catalogue Number: 656320S
• Device Lot Number: 1000505037
• Was Device Available for Evaluation?: Device Returned to Manufacturer
• Date Returned to Manufacturer: 07/18/2023
• Is the Reporter a Health Professional?: No
• Type of Report(Section G): Initial
• Initial Date Received by Manufacturer: 07/03/2023
• Supplement Date Received by Manufacturer: 09/04/2023
• Initial Report FDA Received Date: 07/28/2023
• Supplement Report FDA Received Date: 10/02/2023
• Was Device Evaluated by Manufacturer? (Y/N): Yes
• Date Device Manufactured: 10/27/2022
• 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 Sex: Male