BEUDAMED
    FDA Adverse Event Malfunction Summary report: N

    M.U.S.T. CANNULATED PEDICLE SCREW Ø 6 X 40

    MDR report key: 5124173 · Received October 2, 2015

    Report

    Report Number
    3005180920-2015-00225
    Event Type
    Malfunction
    Date Received
    October 2, 2015
    Date of Event
    September 3, 2015
    Report Date
    November 27, 2015
    Manufacturer
    MEDACTA INTERNATIONAL SA
    Product Code
    NKB
    PMA / PMN Number
    K121115
    Product Problem
    Yes
    Report Source
    Manufacturer report
    Reporter Location
    JA
    Reporter Occupation
    OTHER

    Narratives

    Additional Manufacturer Narrative · 1

    BATCH REVIEW PERFORMED ON 02 OCTOBER 2015: LOT 123930: (B)(4) ITEMS MANUFACTURED AND RELEASED ON 02 OCTOBER 2012. EXPIRATION DATE: 2017-08-31. NO ANOMALIES FOUND RELATED TO THE PROBLEM. TO DATE, (B)(4) ITEMS OF THE LOT HAVE BEEN ALREADY SOLD WITHOUT ANY SIMILAR REPORTED ISSUE. ON (B)(6) 2015 IT WAS ADDED THAT THE THREAD WAS NOT BROKEN BUT JUST SPOILED CAUSING THE SET SCREW COMING OUT FROM THE SCREW HEAD, CRITICAL SIGNS OF DEFORMATION ARE VISIBLE FROM THE PICTURES SENT. PRELIMINARY INVESTIGATION BASED ON THE PICTURES WAS PERFORMED BY THE (B)(4) DIRECTOR ON 10 SEPTEMBER 2015: IT'S CLEARLY VISIBLE ON THE PHOTO PROVIDED THAT THE THREAD OF THE TULIP AS WELL AS THE THREAD OF THE SET SCREW HAS A PLASTIC DEFORMATION. THIS PLASTIC DEFORMATION IS USUALLY CAUSED BY CROSS-THREADING. MEANS THAT THE SURGEON DID NOT PROPERLY ALIGNED THE SET SCREW WITH THE TULIP. DESPITE OF THAT HE FORCED THE SET SCREW INTO THE TULIP WHICH MOST LIKELY HAS RESULTED IN THE FAILURE DESCRIBED. THE SURGEON SHOULD HAVE FELT THAT HE HAS CROSS-THREADED BECAUSE THE INSERTION TORQUE BECOMES HIGHER DUE TO THE IMPROPER ALIGNMENT. IN ANY CASE THE SET HAS AN ENHANCED SET SCREW DRIVER REF. 03.51.10.0128 WITH A GUIDANCE ELEMENT TO ENSURE THAT THE SET SCREW IS PROPERLY ALIGNED WITH THE TULIP. THIS INSTRUMENT SHOULD BE USED IF THE SURGEON DOES NOT FEEL COMFORTABLE WITH THE STANDARD DRIVER. NOT RECEIVED BACK YET.

    Additional Manufacturer Narrative · 1

    VISUAL INSPECTION PERFORMED ON (B)(4) 2015 BY THE R&D PROJECT MANAGER: BOTH SETSCREW AND SCREW HEAD (TULIP) ARE DAMAGED AT THE BEGINNING OF THE THREAD. THE APPEARANCE OF THE DAMAGED AREA SUGGESTS AN EVENT OF CROSS-THREADING, THAT CAN HAPPEN IF THE SETSCREW IS INSERTED NON PERFECTLY ALIGNED TO THE TULIP. THE SETSCREW IS USUALLY INSERTED WITH A TEMPORARY SET-SCREWDRIVER (E.G. 03.51.10.0128) AND AT THIS STAGE THE SURGEON SHOULD VERIFY WHETHER THE SETSCREW IS PROPERLY INSERTED OR IS MISALIGNED. IF IT IS MISALIGNED, DURING THE FOLLOWING STEP OF THE PROCEDURE (FINAL TIGHTENING WITH COUNTER-TORQUE AND TORQUE WRENCH) SETSCREW AND TULIP CAN GET DAMAGED. ACCORDING TO THE PROVIDED INFORMATION, ON THIS PEDICLE SCREW, THE POSITIONING OF THE SETSCREW WAS DIFFICULT BECAUSE THE TULIP WAS MOVED BY THE FORCE OF OTHER MUSCLES. THEREFORE A MISALIGNMENT AND CROSS THREADING IS LIKELY. IN SUCH CASES, THE SURGEON CAN USE DIFFERENT INSTRUMENTS TO PROPERLY MANIPULATE THE TULIP AND GUARANTEE THE CORRECT INSERTION OF THE SETSCREW, SUCH AS THE COUNTER-TORQUE (03.51.10.0064) OR THE "1-STEP REDUCER" (03.51.10.0114) BOTH INCLUDED IN THE STANDARD SET. IN CASE OF MINIMALLY INVASIVE SURGERY THE SCREW HEAD CAN BE MANIPULATED WITH THE SAME ABOVE INSTRUMENTS - IN "MINI OPEN" APPROACH" - OR WITH THE PERCUTANEOUS TOWER (03.52.10.0001, INCLUDED IN THE PERCUTANEOUS SET) TO CONTROL THE POSITION OF THE SCREW HEAD AND GUARANTEE THE CORRECT POSITIONING OF THE SETSCREW. ON 23 NOVEMBER 2015 IT WAS PREPARED A FINAL REPORT WITH THE INFORMATION ALREADY SUBMITTED IN THE INITIAL REPORT AND HERE ABOVE. ON 27 NOVEMBER 2015 IT WAS SENT TO THE INITIAL REPORTER AND THE CASE WAS CLOSED.

    Description of Event or Problem · 1

    THE DOCTOR IMPLANTED A PEDICLE SCREW INTO THE PATIENT. HE TRIED TO TIGHTEN A SET SCREW WITH TORQUE WRENCH AND COUNTER TORQUE WRENCH, BUT HE COULDN'T. THEN HE REPLACED A SET SCREW WITH NEW ONE AND TRIED TO TIGHTEN AGAIN, BUT HE COULDN'T. HE DECIDED TO REPLACE A PEDICLE SCREW WITH NEW ONE BECAUSE HE THOUGHT THE SCREW THREAD IN THE HEAD OF PEDICLE SCREW WAS BROKEN. AFTER THAT HE FOUND THE SCREW THREAD IN THE HEAD OF REMOVAL PEDICLE SCREW WAS BROKEN. THE SURGERY TIME WAS PROLONGED ABOUT 30 MINUTES DUE TO THIS EVENT. NO PATIENT WAS INJURED. TOTAL 7 PEDICLE SCREWS WERE USED IN THIS CASE. ONE IS THE REMOVED PEDICLE SCREW, AND OTHER 6 PEDICLE SCREWS ARE IMPLANTED INTO THE PATIENT. TWO OUT OF 6 IMPLANTED PEDICLE SCREWS ARE SIZE 6X35, BUT OTHER 4 PEDICLE SCREWS ARE THE SAME SIZE AND LOT NUMBER OF REMOVED ONE.

    Devices

    Seq Brand Generic Product Code Manufacturer Model Lot UDI-DI
    656017 M.U.S.T. CANNULATED PEDICLE SCREW Ø 6 X 40 CANNULATED PEDICLE SCREW NKB MEDACTA INTERNATIONAL SA 123930

    Patients

    Seq Age Sex Outcome Treatment
    1 67 YR