BEUDAMED
    FDA Adverse Event Other Summary report: N

    INDEPENDENCE IBOT 4000 MOBILITY SYSTEM

    MDR report key: 873304 · Received June 26, 2007

    Report

    Report Number
    3003508375-2007-00004
    Event Type
    Other
    Date Received
    June 26, 2007
    Date of Event
    May 30, 2007
    Report Date
    June 8, 2007
    Manufacturer
    INDEPENDENCE TECHNOLOGY, L.L.C.
    Product Code
    IMK
    Adverse Event
    Yes
    Report Source
    Manufacturer report
    Reporter Occupation
    PHYSICIAN

    Narratives

    Additional Manufacturer Narrative · 1

    SERVICE WAS DISPATCHED TO INSPECT THE DEVICE AND RETRIEVE THE ELECTRONIC LOG FILE FOR ANALYSIS. A REPORT ON FIELD SERVICE ACTIVITY (SAR) AND A DEVICE CHECKOUT RECORD (FCR) WILL BE FORWARDED TO THE COMPLAINT HANDLING UNIT (CHU) PER STANDARD OPERATING PROCEDURE. ANALYSIS OF THE RETRIEVED LOG FILE (ECF) INDICATES THAT THE USER DID NOT PROPERLY CONTROL THE DEVICE WHILE DESCENDING THE STAIRS IN STAIR CLIMBING FUNCTION. REVIEW INDICATES THAT THE USER DID NOT SUFFICIENTLY CORRECT FOR FORWARD PITCH/MOMENTUM OF THE DEVICE DURING DESCENT. THE ECF DATA SHOWS THAT THIS CAUSED THE VELOCITY OF THE CLUSTER ROTATION TO INCREASE TO AS HIGH AS 219 DEGREES PER SECOND. THE CLUSTER COMPLETED THE ROTATION AT HIGH SPEED AND STRUCK THE LOWER STEP. THE DEVICE THEN BEGAN TO RAPIDLY PITCH FORWARD AND WENT INTO A CLUSTER SAFETY LOCK CONDITION. THE PITCH ANGLE CONTINUED FORWARD UNTIL THE PITCH LIMIT WAS EXCEEDED, AND THE DEVICE WENT TO A CONTROLLER FAILURE CONDITION. AFTER INITIATING A CLIMB DOWN A STAIR STEP, USER'S ARE TRAINED TO CONTROL/SLOW THE RATE OF DESCENT BY MOVING THE USER'S CENTER OF GRAVITY REARWARD OF THE DEVICE REAR WHEELS BY LEANING BACK IN THE SEAT WHILE CLIMBING DOWN THE STEP. IT IS THE REPETITION OF THESE ACTIONS THAT PERMITS STAIR CLIMBING. A MORE DETAILED SUMMARY OF THE ECF ANALYSIS IS ATTACHED TO THIS REPORT. ALL ASSOCIATED ACTIVITIES ARE DOCUMENTED IN COMPLAINT FILES. ADDITIONAL STAIR CLIMBING TRAINING HAS BEEN OFFERED TO THE USER, BUT IS PENDING USER'S MEDICAL CONDITION AT THIS TIME. FROM THE ECF, IN 2007 (18:31:40 GMT), THE PRODUCT ENTERED STAIR FUNCTION. WITHIN 4 SECONDS A FRAME LEAN STOP WAS RECORDED. EIGHTEEN SECONDS LATER, THE DEVICE RECORDED A CONTROLLER ALERT FOR CLUSTER SAFETY LOCK (GOING DOWN). AT THE SAME TIMESTAMP, THE DEVICE WENT TO A CONTROLLER FAILURE CONDITION DUE TO ITS PITCH LIMIT BEING EXCEEDED. NO OTHER PRODUCT FAULTS WERE RECORDED IN THE LOGS THAT CONTRIBUTED TO THIS EVENT. THE BLACK BOX DATA SHOWS THE DEVICE BEGINNING TO PITCH FORWARD AS IT IS ROLLED OFF THE TOP STEP. THE DEVICE PITCH IS SLOWLY AND STEADILY INCREASED OVER THE NEXT 8 SECONDS AS THE CLUSTER ROTATES THROUGH THE DEAD BAND AREA OF PITCH ADJUSTMENT. AFTER 14 DEGREES OF FORWARD PITCH ADJUSTMENT, THE CLUSTER ROTATES OFF THE 1ST STEP. DURING THE CLUSTER ROTATION, THE PITCH IS INCREASED ANOTHER 3 DEGREES. INADEQUATE PITCH CORRECTION AT THE END OF THE ROTATION (ONLY 3.4 DEGREES BEHIND THE ANGLE OF THE ROTATIONS ORIGIN), CAUSED THE VELOCITY OF THE CLUSTER ROTATION TO INCREASE TO AS HIGH AS 219 DEGREES PER SECOND. THE CLUSTER COMPLETES THE ROTATION AT HIGH SPEED AND STRIKES THE LOWER STEP. THE DEVICE THEN BEGINS TO RAPIDLY PITCH FORWARD AND GOES INTO A CLUSTER SAFETY LOCK CONDITION. THE PITCH ANGLE CONTINUED FORWARD UNTIL THE PITCH LIMIT IS EXCEEDED, AND THE DEVICE GOES TO A CONTROLLER FAILURE CONDITION. TESTING AND SIMULATIONS HAVE SHOWN THAT PITCH CORRECTION DURING NORMAL STAIR DESCENT RANGES FROM 12 TO 16 DEGREES BEHIND THE ANGLE OF THE CLUSTER ROTATIONS ORIGIN. 3.4 DEGREES OF PITCH CORRECTION IS NOT ADEQUATE TO SLOW CLUSTER ROTATION AND STOP FORWARD MOMENTUM. BASED ON THE DEVICE LOGS, THE PRODUCT DID NOT MALFUNCTION, AND BEHAVED AS EXPECTED. THE DEVICE ENTERED CLUSTER SAFETY LOCK, AND WENT TO CONTROLLER FAILURE DUE TO THE DEVICE EXCEEDING ITS PITCH LIMIT. CLUSTER SAFETY LOCK IS THE DEVICES DETECTION OF OUT OF CONTROL STAIR CLIMBING.

    Description of Event or Problem · 1

    USER'S HUSBAND REPORTED A FALL IN THE DEVICE. CALLER STATED HIS WIFE WAS DESCENDING A SET OF CONCRETE AND BRICK STAIRS SOLO WHEN THE DEVICE FELL FORWARD, THROWING HER FROM THE DEVICE. CALLER INITIALLY REPORTED HIS WIFE SUSTAINED CONTUSIONS AND WAS TAKEN TO THE ER FOR FURTHER EVALUATION. CALLER IS AN ER PHYSICIAN AND THINKS THERE MAY BE OTHER DAMAGE TO A LEG. CALLER STATES THE DEVICE FELL FORWARD TO THE BOTTOM OF THE STAIRS, ON IT'S BACK. CALLER SUBSEQUENTLY REPORTED THAT THE USER SUSTAINED A BROKEN RIGHT KNEE, WITH DAMAGE TO THE FEMUR AT THE JOINT AND POSSIBLE TIBIA INVOLVEMENT. THE USER REQUIRED SURGERY FOR THE REPORTED INJURIES. THE CALLER ALSO REPORTED THAT THE USER WAS NOT WEARING THE PROVIDED LAP BELT AT THE TIME OF THE EVENT, AND IT WAS THE DEVICE FALLING ON HER THAT CAUSED THE REPORTED INJURY. THIS REPORT CORRESPONDS TO INDEPENDENCE TECHNOLOGY COMPLAINT.

    Devices

    Seq Brand Generic Product Code Manufacturer Model Lot UDI-DI
    1 INDEPENDENCE IBOT 4000 MOBILITY SYSTEM STAIR CLIMBING WHEELCHAIR IMK INDEPENDENCE TECHNOLOGY, L.L.C. NA

    Patients

    Seq Age Sex Outcome Treatment
    1 YR Hospitalization| R