MAUDE Adverse Event Report: STRYKER GMBH LOCKING SCREW VARIAX 2 T10, FULL THREAD, 3.5MM / L16MM; SCREW, FIXATION, BONE

Catalog Number	657316S
Medical Device Problem Code	Migration (4003)
Health Effect - Clinical Code	Insufficient Information (4580)
Date of Event	06/05/2025
Type of Reportable Event	Serious Injury
Event or Problem Description
As reported: "primary surgery was performed on (b)(6) 2025.Two months after surgery, an x-ray revealed that the 2 locking screws inserted on the outside plate had backed out of the plate and the lock had come loose.The screws inserted into the first and third holes from the outer side of the plate backed out.It is unclear which of the screws actually backed out.The patient is originally a farmer and, according to reports, resumed work three weeks after surgery without following the doctor's instructions.Revision surgery is scheduled on (b)(6) 2025".
Additional Manufacturer Narrative
Once the investigation is completed any additional information will be reported in a supplemental report.
Additional Manufacturer Narrative
Please note correction to d1 (product long description), d4 (catalog #), and g1 (reporting contact).The reported event could be confirmed, since based on the provided x-rays and the device return.The device inspection revealed the following: usage marks and discoloration were observed on the screw head and its threads.The threading on the screw head is significantly deformed.The thread no longer follows the standard helical shape and appears to be distorted.This suggests excessive force applied and torsional stress most likely caused the thread to slip, therefore preventing the screw from engaging properly.These evidence indicate this locking screw l16 (lot ak4137) is one of both screws that backed out.All 4 locking screws were inserted into the locking holes of the plates.Each screw was tested for each hole.Despite the observed damages of the plate holes and screws, they could be locked as intended.This event was forwarded to medical affairs, with the following assessment: « clearly the patients postoperative activity might have played a role here.Being a farmer is a heavy duty job, it is conceivable that the arm and shoulder were loaded to much during the healing phase which caused movement in the fracture, implant and screws, loosening them from the plate.There are other factors to consider as well, the screws on the lateral side seem relatively short, and the other factor is that we don¿t know whether the screws were locked properly at all.Based on the provided information, the root cause of the reported event is muti-factorial: the location of the fracture and the technical aspects of the surgical procedure may have contributed to the event.Furthermore, patient activity levels post-op, co-morbidities may also have contributed to an inadequate load distribution, and therefore the breakage of the implant.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 the investigation, the root cause was attributed to a combination of user and patient condition related issue.The implant breakage occurred as a direct result of the patient post-op activity.The choice of the construct and technical aspects of the procedure may also have contributed to the failure of the implant, as the device inspection showed evidence of inadequate insertion and locking of the screws.If more information is provided, the case will be reassessed.
Event or Problem Description
As reported: "primary surgery was performed on (b)(6) 2025.Two months after surgery, an x-ray revealed that the 2 locking screws inserted on the outside plate had backed out of the plate and the lock had come loose.The screws inserted into the first and third holes from the outer side of the plate backed out.It is unclear which of the screws actually backed out.The patient is originally a farmer and, according to reports, resumed work three weeks after surgery without following the doctor's instructions.Revision surgery is scheduled on (b)(6) 2025.".

• Brand Name: LOCKING SCREW VARIAX 2 T10, FULL THREAD, 3.5MM / L16MM
• 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: dannielle stap ; 325 corporate drive; mahwah, NJ 07430 ; 2018315000
• MDR Report Key: 22378051
• Report Number: 0008031020-2025-01040
• Device Sequence Number: 12785225
• Product Code: HWC
• UDI-Device Identifier: 07613327086881
• UDI-Public: (01)07613327086881(17)290831(10)AK4137
• 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: 2025
• Reporter Type: Manufacturer
• Report Source: Health Professional
• Initial Reporter Occupation: Physician
• Type of Report: Initial,Followup
• Report Date (Section B): 09/03/2025

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?: Yes
• Operator of Device: Lay User/Patient
• Device Catalogue Number: 657316S
• Device Lot Number: AK4137
• Was Device Available for Evaluation?: Device Returned to Manufacturer
• Is the Reporter a Health Professional?: Yes
• Type of Report(Section G): Initial
• Initial Date Received by Manufacturer: 06/05/2025
• Supplement Date Received by Manufacturer: 08/04/2025
• Initial Report FDA Received Date: 07/01/2025
• Supplement Report FDA Received Date: 09/03/2025
• Was Device Evaluated by Manufacturer? (Y/N): Yes
• Date Device Manufactured: 09/25/2024
• 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: 81 YR
• Patient Sex: Male
• Patient Ethnicity: Non Hispanic
• Patient Race: Asian