MAUDE Adverse Event Report: STRYKER GMBH CORTEX SCREW S.T. Ø3.5X40MM; PLATE, FIXATION, BONE

Model Number 338640

Device Problems Bent (1059); Material Fragmentation (1261)

Patient Problem No Known Impact Or Consequence To Patient (2692)

Event Date 01/09/2018

Event Type  malfunction  

Manufacturer Narrative

Device will not be returned.If additional information becomes available it will be provided on a supplemental report.Device disposition is unknown.

Event Description

During medical intervention in tibial surgery, axsos screw was damage (broken) and part of it remain in patient, so surgeon decided to removed it (more than 40 minutes).After that the surgeon evidence that the screw in its distal part is bent and smooth.The surgeon use a new screw (longer axsos 3.5x50) to finalize the medical procedure.

Manufacturer Narrative

The reported event that cortex screw s.T.Ø3.5x40mm was alleged of issue s-11 (breakage during surgery) could be confirmed, since the product was returned and matches with the alleged failure.Based on investigation, the root cause was attributed to a user related issue.Failure was most probably caused by failure to follow the op-tech such as - selection of wrong length screw, failure to use a tap for hard bone before screw insertion etc.Excessive application of axial force during screw insertion led to deformation of screw threads and screw breakage.The device inspection revealed the following: visual inspection: the screw shaft broke in the threaded portion close to screw head.The screw threads around distal end of the screw is observed to be severely deformed.The fractured surface near the screw head showed signs of similar to structure typical of a ductile overload breakage.The screw threads on distal end were severly deformed which indicates excessive usage of force for screw insertion in combination with hard bone.It appears that the user did not use a tap for hard bone before screw insertion.Thus it can be concluded that excessive application of torque during screw insertion lead to deformation of screw thread as well as screw breakage.Based on the risk file, screw when used in hard bone, tapping is sometimes necessary.The system offers taps for hard bone.The ifu states that ¿implants can be available in different versions, varying for example in length, diameter, angle, right-hand and left-hand versions, material and number of drilled holes.Select the required version carefully.During the course of the operation, repeatedly check to ensure that the connection between the implant and the instrument, or between the instruments, required for precise positioning and fixing is secure.¿ the instruction for use also mentions that ¿ensure that you are familiar with the intended uses, indications/contraindications, compatibility and correct handling of the implant, which are described in the operative technique manual for the product system¿.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.If any further information is provided, the complaint report will be updated.

Event Description

During medical intervention in tibial surgery, axsos screw was damage (broken) and part of it remain in patient, so surgeon decided to removed it (more than 40 minutes).After that the surgeon evidence that the screw in its distal part is bent and smooth.The surgeon use a new screw (longer axsos 3.5x50) to finalize the medical procedure.

• Brand Name: CORTEX SCREW S.T. Ø3.5X40MM
• Type of Device: PLATE, FIXATION, BONE
• Manufacturer (Section D): STRYKER GMBH; bohnackerweg 1; postfach; selzach 2545 ; CH 2545
• MDR Report Key: 7444279
• MDR Text Key: 106155366
• Report Number: 0008031020-2018-00309
• Device Sequence Number: 1
• Product Code: HRS
• UDI-Device Identifier: 07613327080698
• UDI-Public: (01)07613327080698
• Combination Product (y/n): N
• PMA/PMN Number: K050512
• Number of Events Reported: 1
• Summary Report (Y/N): N
• Report Source: Manufacturer
• Source Type: distributor
• Type of Report: Initial,Followup
• Report Date: 07/03/2018

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Date FDA Received: 04/19/2018
• Is this an Adverse Event Report?: No
• Is this a Product Problem Report?: Yes
• Device Operator: Health Professional
• Device Model Number: 338640
• Device Catalogue Number: 338640
• Device Lot Number: L17288
• Was Device Available for Evaluation?: Device Returned to Manufacturer
• Date Returned to Manufacturer: 05/14/2018
• Date Manufacturer Received: 06/07/2018
• Is This a Reprocessed and Reused Single-Use Device?: No
• Patient Sequence Number: 1
• Patient Outcome(s): Other