BEUDAMED
    FDA Adverse Event Malfunction Summary report: N

    6.5MM, UNIPLANAR SCREW, 40MM (TI-6AL-4V)

    MDR report key: 4898960 · Received July 8, 2015

    Report

    Report Number
    2027467-2015-00113
    Event Type
    Malfunction
    Date Received
    July 8, 2015
    Date of Event
    January 5, 2015
    Report Date
    June 12, 2015
    Manufacturer
    ALPHATEC SPINE INC
    Product Code
    KWP
    PMA / PMN Number
    K100685
    Product Problem
    Yes
    Report Source
    Manufacturer report
    Reporter Occupation
    OTHER

    Narratives

    Additional Manufacturer Narrative · 1

    MDR BEING SUBMITTED AS A RESULT OF A RETROSPECTIVE COMPLAINT REVIEW. A REVIEW OF THE DEVICE HISTORY RECORDS REVEALED NO IRREGULARITIES. THE IMPLANT WAS FOUND TO BE PROPERLY MANUFACTURED AND RELEASED IN ACCORDANCE WITH THE DEVICE MASTER RECORD. VISUAL INSPECTION INDICATED THE BUSHING HAD BEEN ROTATED WITHIN THE BODY OF THE SCREW. THE ROOT CAUSE OF THIS FAILURE MODE HAS BEEN DETERMINED TO BE ADVERTENTLY SPINNING OF THE BUSHING DURING ADJUSTMENTS TO POSITION THE SCREW BODY FOR ROD REDUCTION. THE PURPOSE OF THE UNIPLANAR SCREW IS TO RESTRICT MOTION IN THE AXIAL PLANE SO THE SURGEON CAN MANIPULATE THE VERTEBRAL COLUMN TO CORRECT AXIAL DEFORMITY. TO RESTRICT AXIAL MOTION, THE UNIPLANAR SCREW WAS DESIGNED WITH FLATS ON THE NORMALLY SPHERICAL HEAD OF THE PEDICLE SCREW. THE UNIPLANAR SCREW BUSHING HAS FEATURES WHICH MATE WITH THE FLAT SIDES OF THE PEDICLE SCREW. THE OUTCOME OF THIS DESIGN IS THAT THE UNIPLANAR SCREW ACTS LIKE A FIXED SCREW. TO ADJUST THE ROTATIONAL POSITION OF THE UNIPLANAR SCREW THE PEDICLE SCREW MUST ROTATE. IN CERTAIN INSTANCES THE FRICTION BETWEEN THE SCREW HEAD AND BUSHING CAN BE OVERCOME, AND ROTATION OF THE HEAD DOES NOT RESULT IN THE SIMULTANEOUS ROTATION OF THE BONE SCREW AND BUSHING. THIS RESULTS IN MISALIGNMENT WHICH WILL PREVENT THE ROD FROM FULLY ENGAGING THE SCREW. THIS ISSUE CAN BE MINIMIZED WHEN PROPER TECHNIQUE AND INSTRUMENTS ARE USED. FIELD BULLETIN (B)(4) PROVIDES INSTRUCTIONS FOR IN SITU REALIGNMENT. DO NOT REMOVE THE SCREW. IT CAN BE REALIGNED USE THE FOLLOWING INSTRUMENTS FROM THE ZODIAC INSTRUMENT SET: · (B)(4) SCREW REMOVAL SHAFT · (B)(4) ROD ROCKER 1. ENGAGE THE INNER HEX OF THE UNIPLANAR SCREW WITH THE SCREW REMOVAL SHAFT. YOU WILL USE THE SCREW REMOVAL SHAFT AS AN ANTI-TORQUE TO PREVENT THE SCREW FROM ADVANCING INTO THE PEDICLE WHILE REALIGNING THE BUSHING AND TULIP. 2. USE THE ROD ROCKER TO ENGAGE THE TULIP OF THE UNIPLANAR SCREW. 3. ROTATE THE SCREW HEAD WITH THE ROCKER TO REALIGN THE TULIP WITH THE BUSHING. · USE THE (B)(4) HEAD POSITIONER TO REALIGN THE SCREW HEAD SO THE ROD MAY BE INSERTED. THE ZODIAC SPINAL FIXATION SYSTEM IS INTENDED FOR USE AS A POSTERIOR SPINAL FIXATION DEVICE TO AID IN THE SURGICAL CORRECTION OF VARIOUS SPINAL DEFORMITIES AND PATHOLOGIES OF THE SPINE. IT IS INTENDED TO PROVIDE STABILIZATION DURING THE DEVELOPMENT OF FUSION UTILIZING A BONE GRAFT. SPECIFIC INDICATIONS FOR THE ZODIAC SYSTEM ARE DEPENDENT IN PART ON THE CONFIGURATION OF THE ASSEMBLED DEVICE AND THE METHOD OF ATTACHMENT TO THE SPINE.

    Description of Event or Problem · 1

    THE UNIPLANAR SCREW WAS BEING FINAL TIGHTENED AND IT WAS OBVIOUSLY NOT TORQUING TO 100IN-LBS. ROD WAS REDUCED USING ZDVR UNIPLANAR AXIAL REDUCER. THE SET SCREW WAS REPLACED AND TRIED AGAIN, BUT HAD THE SAME RESULT. AT THAT POINT IT WAS THOUGHT THE HEAD MAY HAVE SPLAYED AND THE SCREW NEEDED TO BE REPLACED.

    Devices

    Seq Brand Generic Product Code Manufacturer Model Lot UDI-DI
    442625 6.5MM, UNIPLANAR SCREW, 40MM (TI-6AL-4V) KWP, MNH, MNI KWP ALPHATEC SPINE INC 22065-40 668764

    Patients

    Seq Age Sex Outcome Treatment
    1 15 YR Other