BEUDAMED
    FDA Adverse Event Injury Summary report: N

    CD HORIZION SPINAL SYSTEM

    MDR report key: 2771835 · Received October 4, 2012

    Report

    Report Number
    1030489-2012-01815
    Event Type
    Injury
    Date Received
    October 4, 2012
    Date of Event
    September 6, 2012
    Report Date
    September 6, 2012
    Manufacturer
    WARSAW ORTHOPEDICS
    Product Code
    KWP
    PMA / PMN Number
    UNK
    Product Problem
    Yes
    Report Source
    Manufacturer report
    Reporter Location
    FL, US
    Reporter Occupation
    PHYSICIAN

    Narratives

    Additional Manufacturer Narrative · 1

    (B)(4): THE PRODUCTS HAVE BEEN RETURNED TO THE MANUFACTURER FOR EVALUATION. ANALYSIS RESULTS ARE NOT AVAILABLE AT THE TIME OF THIS REPORT. A FOLLOW-UP REPORT WILL BE SENT WHEN THE ANALYSIS IS COMPLETE.

    Additional Manufacturer Narrative · 1

    MICROSCOPIC AND SEM EXAMINATION OF THE SET SCREW REVEALED A SIGNIFICANT AMOUNT OF PITTING PRESENT ON THE SET SCREWS WHERE THEY INTERFACE WITH THE MAS THREADS, AS WELL AS AT THE BASE OF THE SET SCREW WHERE IT INTERFACES WITH THE ROD. THE PITTING/CORRODED LOCATIONS ARE COMPONENT INTERFACE POINTS, SPECIFICALLY THE HOOK AND SET SCREW THREADS AND THE SET SCREW BOTTOM FACE AND THE SPINAL ROD. THE CORRODED AREAS SEEN UNDER SEM EXAMINATION APPEARED TO HAVE A STRIATED GRANULAR APPEARANCE WITH CUBICAL VOIDS. THESE VOIDS ARE INDICATIVE OF CHEMICAL ATTACK. THE PITTING SEEN AT THESE CONSTRUCT INTERFACE POINTS, WHEN ASSEMBLED, WOULD PROVIDE CREVICES WHICH CAN PROMOTE IN VIVO CORROSION. THE SET SCREW ARE MADE FROM ASTM F2229 (BIODUR 108) STAINLESS STEEL; THE HOOK AND RODS ARE MADE FROM ASTM F-138 STAINLESS STEEL. ONLY THE SET SCREW WAS EXAMINED UNDER HIGH MAGNIFICATION. SEM MICROSCOPY IDENTIFIED CUBOIDAL PITTING /VOIDS SEEN ON MULTIPLE SET SCREW ROD INTERFACE SURFACES; SAMPLES APPEAR CONSISTENT IN LOCATION AND CORRODED SURFACE MORPHOLOGY TO CREVICE CORROSION. STAINLESS STEEL CORROSION RESISTANCE IS OBTAINED FROM A PASSIVE FILM WHICH FORMS IN AN OXYGEN RICH ENVIRONMENT; THE PRESENCE OF LARGE AMOUNTS OF BIOLOGICAL MATERIAL MAY HAVE GENERATED AN OXYGEN DEFICIENT REGION, RESULTING ANODIC CELL DEVELOPMENT, WHICH WOULD RESULT IN THE LOSS OF THE PASSIVE FILM AND EVENTUAL CORROSION OF THE MATERIAL. ADDITIONALLY, MICRO-MOTION OF THE COMPONENTS MAY HAVE ALSO CONTRIBUTED BY MECHANICALLY REMOVING THE PASSIVE FILM FORMED ON THE STAINLESS STEEL. CRYSTALLOGRAPHIC PITTING IN A CREVICE-TYPE SITUATION TENDS TO INITIATE AT THE CREVICE IN THE CENTER OF THE GRAINS, RATHER THAN AT GRAIN BOUNDARIES. THE PITS GROW, MOST LIKELY ALONG PREFERENTIAL CRYSTALLOGRAPHIC PLANES, TOWARD THE GRAIN BOUNDARIES. THE GROWTH ALONG COMMON PLANES WOULD EXPLAIN THE CONSISTENT ORIENTATION OF ADJACENT CUBICAL VOIDS. AS THESE VOIDS GROW, THE WALLS FROM ADJACENT VOIDS INTERSECT. THE RIDGES LEFT MOST LIKELY FORM THE OBSERVED STRIATIONS. NO OTHER MATERIAL SIGNS OF WEAR, CORROSION, CRACKING, FRACTURE, OR BREAKAGE WERE IDENTIFIED. ELECTRON DISPERSIVE SPECTROSCOPY (EDS) WAS USED TO CHARACTERIZE CHEMISTRY OF THE RETURNED IMPLANTS. EDS ANALYSIS DEMONSTRATED THAT THE ASSOCIATED SET SCREW, HOOK, AND ROD EACH HAD A CHEMICAL COMPOSITION CONSISTENT WITH THAT SPECIFIED IN THE ENGINEERING DRAWINGS. ALL IMPLANTS WERE FOUND TO HAVE CHEMICAL COMPOSITIONS CONSISTENT WITH STAINLESS STEEL. THE NATURE, LOCATION, AND CORRODED SURFACE MORPHOLOGY OF THE RETURNED IMPLANTS ARE CONSISTENT WITH ANTICIPATED IN-VIVO WEAR DUE TO CREVICE CORROSION.

    Additional Manufacturer Narrative · 1

    IF INFORMATION IS PROVIDED IN THE FUTURE, A SUPPLEMENTAL REPORT WILL BE ISSUED.

    Description of Event or Problem · 1

    IT WAS REPORTED THAT THE PATIENT UNDERWENT A 10 LEVEL POSTERIOR LUMBER INTERBODY FUSION FOR A DEFORMITY CORRECTION. SOMETIME POST-OP THE PATIENT UNDERWENT A REVISION DUE TO PAIN. DURING THE REVISION IT WAS FOUND THAT THE HARDWARE HAD A LOT OF CORROSION. SET SCREWS, A HOOK AND A PIECE OF ROD WERE REMOVED. THE REST OF THE CONSTRUCT REMAINED IN PLACE. NO ADDITIONAL PATIENT INFO WAS PROVIDED.

    Devices

    Seq Brand Generic Product Code Manufacturer Model Lot UDI-DI
    1 CD HORIZION SPINAL SYSTEM APPLIANCE, FIXATION, SPINAL INTERLAMINAL KWP WARSAW ORTHOPEDICS NA W07M3068

    Patients

    Seq Age Sex Outcome Treatment
    1 00018 YR SETSCREW, ROD, HOOK