BEUDAMED
    FDA Adverse Event Injury Summary report: N

    STEALTHSTATION S7 SYSTEM

    MDR report key: 4821400 · Received June 5, 2015

    Report

    Report Number
    1723170-2015-00662
    Event Type
    Injury
    Date Received
    June 5, 2015
    Date of Event
    December 31, 2010
    Report Date
    February 19, 2016
    Manufacturer
    MEDTRONIC NAVIGATION, INC. (LOUISVILLE)
    Product Code
    HAW
    PMA / PMN Number
    K050438
    Adverse Event
    Yes
    Report Source
    Manufacturer report
    Reporter Location
    CO, US
    Reporter Occupation
    MEDICAL EQUIPMENT COMPANY TECHNICIAN/REPRESENTATIVE

    Narratives

    Additional Manufacturer Narrative · 1

    CORRECTION: IT WAS DISCOVERED ON 27-JAN-2016, THAT AN INCORRECT DATE WAS REFERENCED IN A PREVIOUS SUPPLEMENTAL 3500A SUBMISSION. THE REPORTED DATE OF 16-AUG-2016 WAS REPORTED INCORRECTLY AND SHOULD BE 16-AUG-2015.STATEMENT IN PREVIOUS SUPPLEMENTAL 3500A SUBMISSION SHOULD READ: ¿ON 30-JUN-2015, IT WAS NOTICED THAT A CODING ERROR IN MDR SUBMISSIONS FROM OUR FACILITY RESULTED IN THE MAUDE DATABASE INCORRECTLY CODING THE DEVICES RELATED TO OUR MDR SUBMISSIONS FROM 25-MAY-2015 TO 16-AUG-2015. THE DECISION TO WAIT UNTIL THE DATABASE WAS CORRECTED WAS MADE AFTER CONSULTATION WITH THE FDA AS ADVISED BY A CONSUMER SAFETY OFFICER WITH THE INFORMATION ANALYSIS BRANCH, DIVISION OF POST MARKET SURVEILLANCE, OFFICE OF SURVEILLANCE AND BIOMETRICS. AN IT SOLUTION WAS IMPLEMENTED ON 16-AUG-2015. THIS MDR WAS SUBMITTED TO CORRECT THE CODING ERROR. THERE IS NO NEW INFORMATION TO CHANGE THE PATIENT INFORMATION, EVENT DESCRIPTION AND/OR MANUFACTURER NARRATIVE THAT WAS PREVIOUSLY REPORTED.¿

    Additional Manufacturer Narrative · 1

    PATIENT IDENTIFIER AND WEIGHT WERE NOT PROVIDED IN THE LITERATURE ARTICLE. EVENT DATE IS ESTIMATED BASED ON THE JOURNAL ARTICLE DATE RANGE OF "BETWEEN 2007 AND 2010". MEDTRONIC REPRESENTATIVE REVIEW DETERMINED PROBABLE CAUSE TO BE THAT SCREW MALPOSITION WAS MORE COMMON IN THE THORACIC LEVELS AND APPEARED TO CORRELATE WELL WITH PEDICLE SIZE (FIGURE 3). ALSO, SOME OF THE ADULTS INCLUDED IN THIS SERIES UNDERWENT SURGERY FOR DEGENERATIVE CONDITIONS, WHICH MAY REDUCE THE DIFFICULTY OF PEDICLE SCREW PLACEMENT. IN CONTRAST, THE MAJORITY OF THE PEDIATRIC PATIENTS IN OUR COHORT (90%) HAD SIGNIFICANT CORONAL PLANE DEFORMITY, WHICH INCREASES THE DIFFICULTY OF PEDICLE SCREW PLACEMENT. THE RATE OF SCREW MISPLACEMENT IS LOWER IN THIS STUDY FOR BOTH ADULT AND PEDIATRIC PATIENTS THAN IF THE SCREWS WERE PLACED WITHOUT NAVIGATION. BETTER KNOWLEDGE OF SCREW POSITION WITH THE IMAGE GUIDANCE SYSTEM ALSO ALLOWED THE SURGEON TO ACCURATELY MEASURE THE DIAMETER AND DEPTH OF EACH PEDICLE AND CUSTOMIZE THE SCREW SIZE TO EACH PEDICLE. THERE WERE SEVERAL SECONDARY EFFECTS FROM THE COMBINATION OF INTRAOPERATIVE NAVIGATION AND THE ABILITY TO OBTAIN AN INTRAOPERATIVE CT PRIOR TO THE CORRECTION. BECAUSE THE SURGEONS IN THIS STUDY HAD THE ABILITY TO ACCURATELY ASSESS THE POSITION OF EACH SCREW UNDER CT IMAGING INTRAOPERATIVELY PRIOR TO DEFORMITY CORRECTION, THE SURGEONS LIKELY HAD A LOWER THRESHOLD FOR SCREW REVISION. IF THE MALPOSITIONED SCREWS WERE DISCOVERED POSTOPERATIVELY AND WERE ASYMPTOMATIC, IT IS POSSIBLE THAT THE SURGEON WOULD DECIDE TO OBSERVE THE PATIENT RATHER THAN RETURN TO SURGERY FOR A SECONDARY PROCEDURE TO REVISE THE SCREW. IN MANY CASES, PEDICLE SCREW MALPOSITION IS ASYMPTOMATIC AND CAN SIMPLY BE OBSERVED, AND RETURN TO SURGERY FOR SCREW REVISION IS RELATIVELY RARE. MOST CHILDREN UNDERGOING POSTERIOR SPINAL INSTRUMENTATION WITH PEDICLE SCREWS DO NOT HAVE POSTOPERATIVE AXIAL IMAGING. THUS, MANY MALPOSITIONED PEDICLE SCREWS MAY BE UNRECOGNIZED, WHICH IS OF UNKNOWN CLINICAL SIGNIFICANCE. NEVERTHELESS, SCREW MALPOSITION CAN RESULT IN CATASTROPHIC COMPLICATIONS AND IT IS ALWAYS DESIRABLE TO AVOID PEDICLE BREACHES, OPTIMIZE PATIENT SAFETY, MAXIMIZE FIXATION, AND IMPROVE SCREW ACCURACY. - NO PARTS HAVE BEEN RECEIVED BY MANUFACTURER FOR ANALYSIS. MEDTRONIC NAVIGATION IS FILING THIS MDR TO ENSURE VISIBILITY TO A PATIENT EVENT AS A RESULT OF A PROCEDURE THAT UTILIZED MEDTRONIC NAVIGATION'S STEALTHSTATION S7 SYSTEM. THERE IS NO ALLEGATION TO SUGGEST THAT MEDTRONIC NAVIGATION'S DEVICE CAUSED OR CONTRIBUTED TO THE REPORTED EVENT.

    Description of Event or Problem · 1

    JOURNAL ARTICLE REVIEW: PEDIATRIC PEDICLE SCREW PLACEMENT USING INTRAOPERATIVE CT AND 3D IMAGE-GUIDED NAVIGATION: LARSON ET.AL. MEDTRONIC NAVIGATION IS FILING THIS MDR TO ENSURE VISIBILITY TO A PATIENT EVENT AS A RESULT OF A PROCEDURE THAT UTILIZED MEDTRONIC NAVIGATION'S STEALTHSTATION S7 SYSTEM. THERE IS NO ALLEGATION TO SUGGEST THAT MEDTRONIC NAVIGATION'S DEVICE CAUSED OR CONTRIBUTED TO THE REPORTED EVENT. PER LARSON, N.A., SANTOS, E.R.G., POLLY, D.W., LEDONIO, C.G.T., SEMBRANO, J.N., MIELKE, C.H., GUIDERA, K.J., BETWEEN 2007 AND 2010, 984 PEDICLE SCREWS WERE PLACED IN 50 PEDIATRIC PATIENTS FOR THE CORRECTION OF SPINAL DEFORMITY. MEAN PATIENT AGE WAS 14.4 YEARS (RANGE, 7-18). THERE WERE 21 MALE AND 29 FEMALE PATIENTS. UNDERLYING DIAGNOSES INCLUDED IDIOPATHIC OR NEUROMUSCULAR SCOLIOSIS (43), SCHEUERMANN¿S KYPHOSIS (3), CONGENITAL HEMIVERTEBRA (2), ACQUIRED KYPHOTIC DEFORMITY AFTER SCOLIOSIS SURGERY (1), THORACIC INSTABILITY AFTER TUMOR RESECTION (1). VALIDITY OF THE SYSTEM WAS INTERMITTENTLY CHECKED BY PLACING A NAVIGATED PROBE ON A KNOWN ANATOMIC LANDMARK AND VISUALLY CORRELATING THE POSITION TO THAT SHOWN ON THE IMAGE GUIDANCE SYSTEM. THIS ENSURED THE REFERENCE FRAME HAD NOT SHIFTED AND THAT THE GUIDANCE SYSTEM WAS STILL PRODUCING CORRECTLY CALIBRATED IMAGES. UNDER IMAGE GUIDANCE WITH THE NAVIGATED INSTRUMENTS, EACH PEDICLE WAS PROBED, TAPPED, AND FILLED WITH A SCREW. FOLLOWING PLACEMENT OF ALL SCREWS, THE COMPUTED TOMOGRAPHY (CT) SCANNER WAS MOVED FROM THE PATIENT¿S HEAD DOWN TO THE OPERATIVE FIELD, AND A SECOND INTRAOPERATIVE CT WAS OBTAINED TO VERIFY SCREW POSITION PRIOR TO ROD PLACEMENT AND DEFORMITY CORRECTION. BASED ON THE FINAL INTRAOPERATIVE CT DATA, ANY CONCERNING SCREWS WERE REMOVED OR REDIRECTED PRIOR TO CORRECTIVE MANEUVERS. OUR PRIMARY OUTCOME MEASURES WERE: 1) THE NUMBER OF SCREWS REVISED AFTER FINAL INTRA-OPERATIVE CT, AND, 2) NEED FOR RETURN TO SURGERY FOR SCREW MALPOSITION. MOTOR EVOKED POTENTIALS AND SOMATOSENSORY POTENTIALS WERE ROUTINELY MONITORED THROUGHOUT THE SURGERY FOR CASES INVOLVING THE THORACIC SPINE. POSTOPERATIVELY, PATIENTS WERE FOLLOWED FOR SIGNS OR SYMPTOMS OF A MALPOSITIONED SCREW. BASED ON THE FINAL INTRAOPERATIVE CT SCAN, 35 SCREWS (3.6%) WERE FOUND TO BE MALPOSITIONED IN THE PEDIATRIC PATIENTS (EXAMPLE, FIGURE 2). THUS, THE ACCURACY RATE OF PEDICLE SCREW PLACEMENT IN PEDIATRIC PATIENTS USING IMAGE-GUIDED NAVIGATION WAS 96.4%. OF THE SCREWS FOUND TO BE MALPOSITIONED, 27 SCREWS WERE REDIRECTED BASED ON THE CT DATA, AND EIGHT SCREWS WERE REMOVED. NO PATIENT RETURNED TO SURGERY FOR SCREW MALPOSITION. THERE WERE NO MAJOR INTRAOPERATIVE OR POSTOPERATIVE NEUROLOGIC OR VASCULAR COMPLICATIONS. DURING THE STUDY PERIOD, 1511 SCREWS WERE PLACED IN ADULT PATIENTS USING THE SAME IMAGE GUIDANCE SYSTEM. SCREW ACCURACY RATES IN THIS COHORT WERE COMPARED TO THE PEDIATRIC PATIENTS. OF THOSE, 28 SCREWS WERE FOUND TO BE MALPOSITIONED ON THE FINAL INTRAOPERATIVE CT SCAN, REPRESENTING A 98.2% ACCURACY RATE. THIS IS STATISTICALLY HIGHER THAN THE 96.4% ACCURACY RATE FOR PEDIATRIC PEDICLE SCREW PLACEMENT USING NAVIGATION (P=0.008). COMPARING OUR RESULTS TO THE LITERATURE, OUR REPORTED PEDIATRIC SCREW ACCURACY RATE FOR NAVIGATION IN CHILDREN IS SIGNIFICANTLY HIGHER THAN THE FINDINGS FROM A RECENT META-ANALYSIS OF PREDOMINANTLY NON-NAVIGATED SCREWS IN CHILDREN, WHICH REPORTS A 94.9% ACCURACY RATE (P=0.03). IT IS INTUITIVE THAT PEDICLE SCREW ACCURACY MAY BE LOWER IN CHILDREN COMPARED TO ADULTS, SINCE PEDICLE SCREWS MAY BE MORE DIFFICULT TO PLACE IN CHILDREN, WITH SMALLER PEDICLE SIZE AND POSSIBLY GREATER DEFORMITY NECESSITATING CHILDHOOD SURGERY. MEDTRONIC NAVIGATION IS FILING THIS MDR TO ENSURE VISIBILITY TO A PATIENT EVENT AS A RESULT OF A PROCEDURE THAT UTILIZED MEDTRONIC NAVIGATION'S STEALTHSTATION S7 SYSTEM. THERE IS NO ALLEGATION TO SUGGEST THAT MEDTRONIC NAVIGATION'S DEVICE CAUSED OR CONTRIBUTED TO THE REPORTED EVENT.

    Devices

    Seq Brand Generic Product Code Manufacturer Model Lot UDI-DI
    364127 STEALTHSTATION S7 SYSTEM NEUROLOGICAL STEREOTAXIC INSTRUMENT HAW MEDTRONIC NAVIGATION, INC. (LOUISVILLE) S7

    Patients

    Seq Age Sex Outcome Treatment
    1 14 YR Required Intervention