BEUDAMED
    FDA Adverse Event Injury Summary report: N

    MISONIX BONESCALPEL SYSTEM MXB-20 BONESCALPEL - 20MM, BLUNT BLADE

    MDR report key: 7071144 · Received November 30, 2017

    Report

    Report Number
    2435119-2017-00007
    Event Type
    Injury
    Date Received
    November 30, 2017
    Date of Event
    October 16, 2017
    Report Date
    November 28, 2017
    Manufacturer
    MISONIX, INC.
    Product Code
    LFL
    UDI-DI
    00841626101142
    PMA / PMN Number
    K070313
    Adverse Event
    Yes
    Product Problem
    Yes
    Report Source
    Manufacturer report
    Reporter Location
    AS
    Reporter Occupation
    MEDICAL EQUIPMENT COMPANY TECHNICIAN/REPRESENTATIVE

    Narratives

    Additional Manufacturer Narrative · 1

    THIS REPORT IS FOR A PATIENT WHO SUSTAINED A DURAL LEAK. THE SURGEON SPECULATED THAT THE BLADE OVERHEATED CAUSING A SCARRING OF THE DURA AND NECROSIS, WHICH IN TURN CAUSED A DURAL LEAK SIX DAYS AFTER THE SURGERY WAS COMPLETED. A REVISION SURGERY WAS REQUIRED TO REPAIR THE DURAL LEAK. THE PATIENT'S SYMPTOM PRIOR TO THE REPAIR WAS A LOW-PRESSURE HEADACHE. THE REPORTER REPORTED THE PART AS MISONIX BONESCALPEL MXB-20 ULTRASONIC SURGICAL SYSTEM 20MM BLUNT BLADE, LOT # 1111319. THE REPORTER INDICATED THE BLADE HAD DARKENED. THIS WAS THE SURGEON'S FIRST TIME USING THE BONESCALPEL ULTRASONIC SYSTEM. MISONIX REPRESENTATIVES HAD PERFORMED IN-SERVICE TRAINING PRIOR TO THE CASE AND THE HOSPITAL STAFF HAD PRIOR EXPERIENCE WITH THE SYSTEM, EVEN THOUGH THIS WAS THE FIRST TIME THE SURGEON WAS USING THE SYSTEM. MISONIX CONTACTED THE CUSTOMER ACCOUNT, REQUESTING THAT ALL SUSPECT PRODUCT BE RETURNED, FOLLOWING OUR STANDARD PROCESS, HOWEVER THE REPORTER DID NOT RETURN THE SUSPECT BLADE FOR ANALYSIS. THEREFORE AN ENGINEERING EVALUATION COULD NOT BE PERFORMED. NO PHOTOGRAPHS OF THE SUSPECT BLADE WERE PROVIDED. THE BONESCALPEL SYSTEM WAS TESTED IN ACCORDANCE WITH IEC 60601-1 "MEDICAL ELECTRICAL EQUIPMENT - PART 1: GENERAL REQUIREMENTS FOR BASIC SAFETY AND ESSENTIAL PERFORMANCE" SECTION 11.1 "PROTECTION AGAINST EXCESSIVE TEMPERATURES AND OTHER HAZARDS, EXCESSIVE TEMPERATURES IN ME EQUIPMENT" DURING DESIGN VERIFICATION. THE SYSTEM AND APPLIED PARTS (INCLUDING THE MXB-20) CONFORMED TO THE MAXIMUM TEMPERATURE SPECIFICATIONS DURING WORST-CASE NORMAL USE CONDITIONS FOR APPLIED PARTS (SKIN CONTACT PARTS). , THE BLADE MET ALL INCOMING INSPECTION REQUIREMENTS FOR BOTH THE TITANIUM BLADE AND STERILE PACKAGE. IT IS COMMON FOR TITANIUM TO DARKEN WITH THE APPLICATION OF ULTRASOUND DURING SURGERY, ESPECIALLY DURING THE BONE REMOVAL PROCESS IN APPLICATIONS SUCH AS A LAMINECTOMY. MISONIX DOES NOT BELIEVE THERE IS A CAUSAL EFFECT OF DARKENING TO TISSUE NECROSIS. TREND ANALYSIS WAS PERFORMED FOR DURAL INJURY. DURING THE TIME PERIOD 10/06/2015 TO 11/21/2017 THERE HAVE BEEN 3 ADVERSE EVENTS REPORTED FOR SPINAL/DURAL DAMAGE FOR THE BONESCALPEL SYSTEM (ALL PROBE DESIGNS). THE DEFECTIVE RATE IS BASED ON THE AREA OF OPPORTUNITY DEFINED AS THE NUMBER OF PROCEDURES PERFORMED DURING THAT TIME PERIOD, WHICH IN TURN IS ESTIMATED BY TUBING SET SALES FOR THAT TIME PERIOD, 71,847. THE ADVERSE EVENT RATE IS 0.004 %. ADDITIONALLY, A REVIEW OF THE RMA FILE INDICATES THAT DURING THE IMMEDIATE 12 MONTHS PRIOR TO THE DATE OF THIS COMPLAINT, THERE WERE NO ADVERSE EVENTS SPECIFICALLY FOR MXB-20. DURING THIS TIME 17,214 MXB-20 BLUNT BLADES WERE INTRODUCED INTO COMMERCE. THE PRE-PROGRAMMED DEFAULT SYSTEM SETTINGS FOR THE BONESCALPEL SYSTEM ARE; VIBRATION SETTING OF 7, IRRIGATION FLOW RATE OF 70%, AND PULSE SETTING OF 100. THESE SETTINGS ASSURE THERMAL EQUILIBRIUM DURING THE APPLICATION OF ULTRASOUND WHEN MAKING CUTS IN BONE. THESE PRE-PROGRAMMED SETTINGS, ACT AS A FAILSAFE MECHANISM, REQUIRING A COGNITIVE DECISION BY THE USER TO CHANGE THE VIBRATION AND IRRIGATION FLOW RATE. IN THE SUBJECT CASE, THE SURGEON STATED THAT IRRIGATION WAS DECREASED TO 30%, WHILE THE VIBRATION WAS INCREASED TO 9, AND A PULSE SETTING OF 100. IN THIS CASE, THERE IS DISPROPORTIONAL AMPLITUDE SETTING COMPARED TO THE IRRIGATION SETTING. THESE DISPROPORTIONATE SETTING CAN AFFECT THE THERMAL EQUILIBRIUM AND CAUSE SELF-HEATING OF THE PROBE. THE BONESCAPEL IFU STATES THE FOLLOWING WARNINGS AND CAUTIONS WITH REGARD TO PROPER USE TO AVOID EXCESSIVE HEATING AND POSSIBLE NECROSIS: WARNING 3.1 TIP AND IRRIGANT TEMPERATURES MAY EXCEED THE TISSUE NECROSIS POINT IF INSUFFICIENT IRRIGATION FLOW RATES ARE USED. FOR HARD TISSUE REMOVAL, SET THE IRRIGATION FLOWRATE TO A SETTING NO LESS THAN THE COMPARABLE VIBRATION SETTING. FOR EXAMPLE, IF THE VIBRATION SETTING IS 7, A MINIMUM FLOW SETTING OF 70% SHOULD BE USED. ADDITIONAL EXTERNAL IRRIGATION, E.G. BY ADMINISTERING STERILE SALINE WITH A SYRINGE OVER THE DISTAL TIP PORTION, MAY BE NECESSARY FOR REMOVAL OF VERY DENSE, HARD OSSEOUS STRUCTURES. WARNING 3.2 TISSUE NECROSIS MAY RESULT IF TIP IS NOT MOVED RELATIVE TO TISSUE. A CONTINUOUS, LATERAL SWEEPING MOTION IS RECOMMENDED IN ORDER TO MINIMIZE CONTACT DURATION WITH THE ULTRASONIC TIP AND MINIMIZE HEAT BUILD-UP. WHEN LATERAL MOTION IS NOT POSSIBLE WITHDRAW AND RE-INSERT TIP FREQUENTLY. WARNING 4.1 CONTACT TO VIBRATING ELEMENTS LIKE EXTENSION AND ULTRASONIC TIP MAY CAUSE BURNS AND SHOULD BE AVOIDED BY ALL MEANS. THE HANDPIECE SHOULD ONLY BE HELD AT THE BLACK HOUSING AREA. AN OPTIONAL, PROTECTIVE SILICONE SLEEVE, INCLUDED WITH CERTAIN TIPS, REDUCES THE RISK OF THERMAL DAMAGE BUT DOES NOT ELIMINATE IT. CONTACT WITH THE SILICONE SLEEVE SHOULD BE AVOIDED OR KEPT BRIEF WITH MINIMAL AMOUNT OF CONTACT PRESSURE. PRESSURE AND EXTENDED EXPOSURE CAN STILL RESULT IN EXCESSIVE FRICTIONAL HEAT AND CAUSE BURNS. WARNING 4.2 ADDITIONAL EXTERNAL IRRIGATION, E.G. BY ADMINISTERING STERILE SALINE WITH A SYRINGE OVER THE DISTAL TIP PORTION, MAY BE NECESSARY FOR REMOVAL OF VERY DENSE, HARD OSSEOUS STRUCTURES OF THE SKULL, WHEN USING THE BONESCALPEL ACCESSORIES. WARNING 7.3 TIP AND IRRIGATION TEMPERATURES MAY EXCEED THE TISSUE NECROSIS POINT WITH BONESCALPEL ACCESSORIES FOR HARD TISSUE REMOVAL IF INSUFFICIENT IRRIGATION FLOW RATES ARE USED. ALWAYS SET THE IRRIGATION FLOWRATE FOR HARD TISSUE REMOVAL TO A SETTING NO LESS THAN THE COMPARABLE VIBRATION SETTING. FOR EXAMPLE, IF THE VIBRATION SETTING IS 7, A MINIMUM FLOW SETTING OF 70% SHOULD BE USED. WARNING 7.4 HEAT IS BEING GENERATED AT THE TIP/TISSUE INTERFACE. A CONTINUOUS, LATERAL SWEEPING MOTION IS RECOMMENDED FOR GENERAL BONE/TISSUE REMOVAL IN ORDER TO MINIMIZE CONTACT DURATION WITH THE ULTRASONIC TIP AND MINIMIZE THE TEMPERATURE INCREASE. CAUTION 4.1 ULTRASONIC ENERGY IS INHIBITED IF EXCESSIVE PHYSICAL FORCE IS APPLIED TO THE ULTRASONIC TIP; USE ONLY ENOUGH FORCE TO GUIDE THE TIP TO THE SURGICAL SITE AND TO ADVANCE IT THROUGH THE TISSUE. DO NOT FORCE THE TIP; ALLOW THE ULTRASONIC ACTION TO DO THE WORK. CAUTION 4.2 INSUFFICIENT IRRIGATION AND HIGH TIP PRESSURE (LOADING) UNDER EXTENDED EXPOSURE, E.G. IN TIGHT CAVITIES, ARE TO BE AVOIDED IN BONESCALPEL HARD TISSUE REMOVAL. IT IS RECOMMENDED TO WITHDRAW AND RE-INSERT THE ULTRASONIC TIP REPEATEDLY TO RE-ESTABLISH ADEQUATE COOLING AND LUBRICATION. TABLE 4.1 RECOMMENDED SETTINGS. · A HIGH AMPLITUDE SETTING RESULTS IN MORE AGGRESSIVE TISSUE REMOVAL, A LOW SETTING IN LESS AGGRESSIVE TISSUE REMOVAL. · A HIGHER AMPLITUDE SETTING IN COMBINATION WITH LOWER IRRIGATION COULD RESULT IN INCREASED TISSUE NECROSIS. A LOWER AMPLITUDE SETTING IN COMBINATION WITH HIGHER IRRIGATION WOULD MINIMIZE OR ELIMINATE TISSUE NECROSIS. IRRIGATION (PG. 25 BCM-UM REV P). PROPER IRRIGATION WITH STERILE SALINE ENSURES: 1. COOLING OF HANDPIECE AND VIBRATING ELEMENTS. 2. COOLING AND LAVAGE OF THE SURGICAL SITE. 3. LUBRICATION OF BONE/TIP INTERFACE FOR BONESCALPEL HARD TISSUE REMOVAL. THE ACTIVE ULTRASONIC PROBE REMAINS COLD WHEN NOT IN CONTACT WITH TISSUE. HOWEVER, WHEN A TIP CONTACTS TISSUE HEAT IS GENERATED. THE HEAT INCREASES WITH APPLIED TIP PRESSURE OR AMPLITUDE. IRRIGANT NEEDS TO BE APPLIED AT THE TIP/TISSUE INTERFACE TO MITIGATE THIS TEMPERATURE RISE. MOST ULTRASONIC TIPS AND PROBES FEATURE AN INTEGRATED IRRIGATION CHANNEL. THE IRRIGANT IS EXPELLED THROUGH A JET NOZZLE AT THE TIP. ACTIVE TIP SURFACES ARE BEING COOLED DIRECTLY. INCIDENTAL DUROTOMIES ARE A WELL KNOW COMPLICATION IN SPINE SURGERY. (BYDON M, XU R, PAPADEMETRIOU K, SCIUBBA DM, WOLINSKY JP, WITHAM TF, GOKASLAN ZL, JALLO G, BYDON A. J NEUROSURG SPINE. 2013 JUN;18(6):627-33. PMID: 23560712) (HU X, OHNMEISS DD, LIEBERMAN IH. EUR SPINE J. 2013 APR 16. PMID: 23584231). THESE TWO PUBLICATIONS CONCLUDE THAT THE BONESCALPEL SURGICAL SYSTEM IS SAFE FOR A VARIETY OF SPINE SURGERIES. HOWEVER, CAUTION SHOULD BE TAKEN AS INDICATED IN THE IFU WARNINGS AND CAUTIONS TO AVOID POTENTIAL THERMAL INJURY AND DUROTOMY . CONCLUSION: BASED ON THE INFORMATION PROVIDED, THERE DOES NOT APPEAR TO BE A MALFUNCTION OF THE DEVICE THAT CAUSED OR CONTRIBUTED TO THE ADVERSE EVENT. THERE IS NO DEFINITIVE ROOT CAUSE. A POTENTIAL ROOT CAUSE IS THAT THE DEVICE WAS PUT INTO A STATE WHERE THERMAL EQUILIBRIUM COULD NO LONGER BE MAINTAINED. THIS WOULD HAVE RESULTED FROM THE USER REDUCING THE IRRIGATION FLOW RATE AND INCREASING THE VIBRATION SETTING TO A DISPROPORTIONATE CONDITION IN RELATIONSHIP TO THE RECOMMENDATIONS IN THE IFU TO SET THE IRRIGATION FLOWRATE FOR HARD TISSUE REMOVAL TO A SETTING NO LESS THAN THE COMPARABLE VIBRATION SETTING. OUR LITERATURE SEARCH INDICATES THAT DUROTOMIES ARE A "WELL KNOWN" COMPLICATION IN SPINE SURGERY AND THEREFORE A KNOWN RISK. COMPLAINT TRENDING ANALYSIS SUGGESTS THAT OCCURRENCES OF EVENTS INCLUDING A DURAL LEAK ARE WELL BELOW EXPECTED FREQUENCIES FOR SPINAL SURGERY.

    Description of Event or Problem · 1

    THE VERBATIM REPORT FROM THE USER IS AS FOLLOWS: DETAILS : (B)(6) 2017 - PROF (B)(6) WAS PERFORMING A LAMINECTOMY OF L5-S1. AT THE END OF THE CASE WE NOTICED THE BLADE HAD BLACKENED, SUGGESTING OVERHEATING. WE HAD REDUCED THE IRRIGATION TO 30% DUE TO COMPLAINTS ABOUT TOO MUCH WATER IN THE WOUND. THE PULSE HAD BEEN RAISED TO 9. AFTER SHOWING NO ADVERSE EFFECTS POST OP FOR 2 OR 3 DAYS, THE PATIENT SHOWED SYMPTOMS CONSISTENT WITH A DURAL LEAK. THE PATIENT WAS REVISED 5 DAYS LATER ON (B)(6) 2017. PROF (B)(6) REPORTS A NECROSED SCAR ON THE DURA IN LINE WITH THE LAMINA REMOVAL. HIS STRONG BELIEF IS THAT THE BLADE HAD BURNT THE DURA AND THE NECROSED TISSUE HAS GRADUALLY GIVEN WAY, LEADING TO THE LEAK.

    Devices

    Seq Brand Generic Product Code Manufacturer Model Lot UDI-DI
    849935 MISONIX BONESCALPEL SYSTEM MXB-20 BONESCALPEL - 20MM, BLUNT BLADE ULTRASONIC SURGICAL SYSTEM LFL MISONIX, INC. MXB-20 1111319 00841626101142

    Patients

    Seq Age Sex Outcome Treatment
    1 43 YR Hospitalization| R