BEUDAMED
    FDA Adverse Event Malfunction Summary report: N

    TILITE ZR SERIES 2

    MDR report key: 2177697 · Received July 1, 2011

    Report

    Report Number
    3032618-2011-00002
    Event Type
    Malfunction
    Date Received
    July 1, 2011
    Date of Event
    April 1, 2011
    Report Date
    June 30, 2011
    Manufacturer
    TISPORT, LLC
    Product Code
    IOR
    PMA / PMN Number
    K990358
    Adverse Event
    Yes
    Report Source
    Manufacturer report
    Reporter Occupation
    NOT APPLICABLE

    Narratives

    Additional Manufacturer Narrative · 1

    EVAL SUMMARY: THE PARTS RETURNED TO US CONSISTED OF THE COMPLETE WHEELCHAIR. INSPECTION: BASED UPON VISUAL INSPECTION, IT IS APPARENT THAT THE BACKREST PIVOT STUD ON THE RIGHT SIDE BACKREST HINGE ASSEMBLY WAS BROKEN, THEREBY SEVERING THE CONNECTION BETWEEN THE BACK MOUNT BRACKET (WHICH IS ATTACHED TO THE SEAT TUBE OF THE WHEELCHAIR) AND THE BACKREST PIVOT ASSEMBLY (WHICH IS ATTACHED TO THE TITANIUM BACKREST). HOWEVER, WHEN RETURNED TO US, THE BACKREST PIVOT ASSEMBLY HAD BEEN REATTACHED TO THE BACK MOUNT BRACKET UTILIZING THE UPPERMOST HOLE IN THE BACK MOUNT BRACKET (WHICH HOLE IS RESERVED FOR USE WITH THE LOCKDOWN VERSION OF THE BACKREST). AS A RESULT, THE BACKREST RELEASE BAR AND LATCH WERE NOT CORRECTLY ALIGNED WITH THE LOCKING BLOCK/ANGLE ADJUSTMENT STUD. FURTHER INSPECTION REVEALED THAT A ROUGH EDGE OF THE BROKEN BACKREST PIVOT STUD HAD WORN AWAY A SIGNIFICANT AMOUNT OF MATERIAL FROM THE BACK MOUNT BRACKET, WITH MOST OF THE WEAR BEING IMMEDIATELY AFT OF THE HOLE THROUGH WHICH THE BACKREST PIVOT STUD IS MOUNTED IN THE BACK MOUNT BRACKET. IN ADDITION, THERE WERE SCRATCHES LOCATED AROUND THE UPPER PORTION OF THE BACK MOUNT BRACKET. THE LOCK BLOCK ON THE RIGHT SIDE OF THE CHAIR (USED TO ADJUST THE ANGLE OF THE BACKREST) WAS SECURELY ATTACHED TO THE BACK MOUNT BRACKET, WITH MINIMAL EVIDENCE OF WEAR IN THE INTERLOCKING GROOVES ON THE BACK MOUNT BRACKET OR ON THE LOCK BLOCK. THERE WAS EVIDENCE OF WEAR ON THE BACKREST PIVOT ASSEMBLY NEAR THE EARS WHICH SECURE THE BACKREST LATCH TO THE BACKREST PIVOT ASSEMBLY. IN ADDITION, IT WAS VISUALLY NOTED THAT THE LEFT SIDE BACKREST PIVOT STUD WAS INTACT. THERE WAS MINIMAL EVIDENCE IN THE INTERLOCKING GROOVES ON THE BACK MOUNT BRACKET OR TON THE LOCK BLOCK. HOWEVER, THERE WAS EVIDENCE OF SUBSTANTIAL WEAR ON THE BACKREST PIVOT ASSEMBLY NEAR THE EARS WHICH SECURE THE BACKREST LATCH TO THE BACKREST PIVOT ASSEMBLY. IT APPEARED AS THOUGH THE MISALIGNMENT OF THE BACKREST LATCHES, CAUSED BY THE IMPROPER REATTACHMENT OF THE RIGHT BACKREST PIVOT ASSEMBLY TO THE TIGHT BACK MOUNT BRACKET, IN TURN, CAUSED THE LEFT BACKREST PIVOT ASSEMBLY TO RUB AGAINST THE LEFT LOCK BLOCK. TESTING: TO STIMULATE THE FAILURE OF THE RIGHT SIDE PIVOT STUD, A SIMILAR WHEELCHAIR MODEL WAS REMOVED FROM THE ASSEMBLY LINE AND THE PIVOT STUD IN QUESTION WAS COMPLETELY REMOVED FROM THE BACKREST BRACKET ASSEMBLY. WITH THIS BACKREST PIVOT STUD REMOVED, IT WAS NOTED THAT WHEN THE BACKREST WAS LOCKED IN THE UPRIGHT POSITION (THE POSITION IT WOULD BE IN WHEN THE PT WAS RIDING IN THE WHEELCHAIR), THERE WAS MORE "PLAY" IN THE BACKREST THAN IF THE BACKREST PIVOT STUD HAD NOT BEEN REMOVED. IT WAS ALSO NOTED THAT WHEN ATTEMPTING TO FOLD DOWN THE BACKREST, IT BECAME DIFFICULT TO OPERATE THE FOLDING MECHANISM SMOOTHLY WITH ONLY ONE FUNCTIONAL BACKREST PIVOT STUD. FURTHER, IT WAS NOTED THAT IT WAS SOMETIMES DIFFICULT TO GET THE BACKREST TO PROPERLY ENGAGE IN THE LOCKED, UPRIGHT POSITION WHEN THE BACKREST PIVOT STUD HAD BEEN REMOVED. TO DETERMINE WHAT CAUSED THE BACKREST PIVOT STUD TO FAIL, WE ATTEMPTED TO CAUSE A FAILURE BY APPLYING EXCESSIVE FORCE TO THE SINGLE BACKREST PIVOT STUD ON THE WHEELCHAIR REMOVED FROM THE ASSEMBLY LINE. WE COULD NOT ACHIEVE A FAILURE USING FORCE OF A MAGNITUDE BELIEVED TO BE GREATER THAN THAT NORMALLY EXPERIENCED IN REGULAR USE OF THE PRODUCT. RATHER THE BACK MOUNT BRACKED YIELDED BEFORE THERE WAS. ANALYSIS: IN LIGHT OF THE FOREGOING INSPECTION AND TESTING, WE CONCLUDE AS FOLLOWS: THE EXCESSIVE WEAR ON THE RIGHT BACK MOUNT BRACKET WAS CAUSED BY THE BROKEN BACKREST PIVOT STUD, INDICATING THAT THE PT CONTINUED TO USE THE WHEELCHAIR FOR A SIGNIFICANT AMOUNT OF TIME AFTER THE BACKREST PIVOT STUD FAILED. OUR TESTING CONFIRMED THAT THE WHEELCHAIR WAS STILL FUNCTIONAL WITH THIS BOLT MISSING, BUT THAT THERE WAS EXCESSIVE "PLAY" WHICH WOULD LIKELY TRIGGER A CALL TO THE SERVICE PROVIDER TO INSPECT THE PRODUCT SINCE IT SEEMED TO BE NOT FUNCTIONING PROPERLY. IT IS NOT KNOWN IF THE PT PLACED SUCH A CALL. WHEN RETURNED TO US, THE RIGHT SIDE BACKREST BRACKET HAD BEEN REASSEMBLED INCORRECTLY. THIS IN TURN CAUSED THE DAMAGE TO THE LEFT SIDE BACKREST BRACKET ASSEMBLY. IT SEEMED TO BE THE CASE THAT THIS PT CONTINUED TO UTILIZE THE PRODUCT AFTER DISCOVERING THE BROKEN PIVOT BOLT, WHICH IN TURN CAUSED FURTHER DAMAGE TO THE PRODUCT. FURTHERMORE, THE WAY IN WHICH THIS PRODUCT WAS RE-ASSEMBLED ENSURE THAT IT WOULD NOT FUNCTION CORRECTLY AND THAT WOULD LIKELY HAVE CAUSED THE PT TO EXPERIENCED A SHIFT IN HIS CENTER OF GRAVITY, WHICH IN TURN LIKELY CAUSED HIS FALL FROM THE WHEELCHAIR. BASED ON THE FOREGOING EVIDENCE, OUR CONCLUSION IS THAT WHILE THE BACKREST PIVOT STUD FAILED PREMATURELY, THIS DID NOT DIRECTLY CAUSE THE ACCIDENT. AT MOST, THIS FAILURE TRIGGERED A SERIES OF EVENTS THAT CULMINATED IN HUMAN ERROR THAT DIRECTLY TRIGGERED THE ACCIDENT.

    Description of Event or Problem · 1

    THE PT STATES THAT A BACKREST BOLT BROKE AND HE FLIPPED OUT OF HIS CHAIR CAUSING A "SCAR ON HIS RODS. IT IS NOT CLEAR WHETHER THE PT WAS REFERRING TO RODS THAT MAY HAVE BEEN IMPLANTED IN HIS BACK RELATIVE TO A SPINAL CORD INJURY OR IF HE WAS REFERRING TO DAMAGE TO THE BACKREST OF THE WHEELCHAIR.

    Devices

    Seq Brand Generic Product Code Manufacturer Model Lot UDI-DI
    1 TILITE ZR SERIES 2 WHEELCHAIR, MECHANICAL IOR TISPORT, LLC ZR SERIES 2

    Patients

    Seq Age Sex Outcome Treatment
    1 Other