MAUDE Adverse Event Report: AESCULAP INC ARCADIUS HEXALOBE FLEX DRIVER; INSTRUMENTS INTERBODY FUSION

Model Number ME053R

Device Problem Structural Problem (2506)

Patient Problem No Known Impact Or Consequence To Patient (2692)

Event Date 02/22/2018

Event Type  malfunction  

Manufacturer Narrative

Manufacturing site evaluation: upon receipt of the product, it was noticed that the threads were twisted and unusable.The product was then sent further for investigation.Tek park inspection: initial inspection of the driver part at the test lab showed a large variance in the hardness of the shaft.Per the top level drawing for the item, the material used in the driver (carpenter custom 465 stainless steel) should have an hrc harness between 47 and 51 rockwell.Parts of the flexible shaft varied from 48.5 hrc at the weld to 20 hrc on the shaft.The front of the flexible shaft was 31 hrc.The hexalobe section, due to the small size, was very difficult to test for hardness and no value could be directly determined.The test sample was destroyed during the hardness testing.This mismatch of tested hardness values from expected hardness values indicated three possible situations: - the heat treatment was either not conducted, or conducted incorrectly, - the wrong material was used, - the weld of the tip to the flexible shaft, and the weld of the flexible shaft to the coupler affected the heat treatable nature of the stainless steel.The heat treatment of the shaft could not be independently verified without relying on the supplier documentation.An me053r article (not the product reported as damaged in surgery) was sent to carpenter, with instructions to identify the material and to determine if the material was effectively heat treated.A report was received back indicating that the material was custom 465, but that the weld adversely affected the material and would not allow for proper heat treatment.Carpenter (supplier) evaluation: problem: a medical instrument is produced by tig welding custom 465 parts into as assembly using 630 filler wire.The end of the device (torx driver) did not respond to precipitation heat treatment (950 f/4 hrs) and it is only very slightly magnetic.Results - the driver assembly examined and a closeup view of the tip was performed.The tip was confirmed to be custom 465 using portable x-ray analysis as well as wet chemical analysis.The tip was sectioned longitudinally.There was a transition in microstructure from the weld zone to the tip.The tip region appears to be fully reverted to austenite.Vickers microhardness readings were taken from the weld zone to the tip.Conclusion: the low hardness and non-magnetic condition in the tip of the driver appears to be a result of over-heating from the welding process.The area near the weld apparently was exposed to temperatures high enough to result in a solution treated condition which then responded to the precipitation heat treatment.Past the area of re-solutioned structure the temperatures were high enough to over-age the structure and result in a high degree of austenite reversion but not high enough to result in a re-solutioned condition.This area, as would be expected, did not respond to precipitation hardening.Recommendation: using a lower heat input welding process would limit the area which is over-aged to a much smaller zone near the weld.Laser or electron beam welding could be considered to reduce the heat input which was experienced with the tig welding.If it is necessary to continue with the tig welding process, a full post weld heat treatment should restore the precipitation hardening response to the full assembly.The spring and pin portions of the assembly would need to be withheld until after the heat treatment was completed.The additional heat treatment required (as shown in carpenter's alloy data sheet) would be: heat to 1800°f±15°f (982°c±8°c), hold one hour at heat and cool rapidly.Sections up to 12" can be quenched in a suitable liquid quenchant.Sections over 12" should be cooled rapidly in air.For optimum aging response, solution annealing should be followed by refrigerating to -100°f (-73°c), holding eight hours, then warming to room temperature (ct).Subzero cooling should be performed within 24 hours of solution annealing.It should be noted that the cold worked condition of the original bar stock would be eliminated in the process of post weld solution heat treating.Action: a capa was requested and a scar was opened.The decision was made to source the product from a different supplier, and products were removed from the field and no longer distributed.

Event Description

It was reported that there was an issue with an arcadius hexalobe flex driver.During an alif procedure, it was noted that the screws would not stay on the screwdriver.It appeared to be a malfunction of the tip of the driver, and it would not hold a screw.There was a 5-minute delay in surgery.There was no patient harm and no intervention was required.

• Brand Name: ARCADIUS HEXALOBE FLEX DRIVER
• Type of Device: INSTRUMENTS INTERBODY FUSION
• Manufacturer (Section D): AESCULAP INC; 3773 corporate parkway; center valley PA 18034
• Manufacturer (Section G): AESCULAP INC; 3773 corporate parkway; center valley PA 18034
• Manufacturer Contact: lindsay chromiak ; 3773 corporate parkway; center valley, PA 18034
• MDR Report Key: 9306224
• MDR Text Key: 170908047
• Report Number: 2916714-2019-00116
• Device Sequence Number: 1
• Product Code: HXX
• Combination Product (y/n): N
• Reporter Country Code: US
• PMA/PMN Number: EXEMPT
• Number of Events Reported: 1
• Summary Report (Y/N): N
• Report Source: Manufacturer
• Source Type: company representative,user f
• Reporter Occupation: Other Health Care Professional
• Type of Report: Initial
• Report Date: 11/11/2019

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Is this an Adverse Event Report?: No
• Is this a Product Problem Report?: Yes
• Device Operator: Health Professional
• Device Model Number: ME053R
• Device Catalogue Number: ME053R
• Device Lot Number: 1017002
• Was Device Available for Evaluation?: Yes
• Is the Reporter a Health Professional?: Yes
• Initial Date Manufacturer Received: 02/23/2018
• Initial Date FDA Received: 11/11/2019
• Was Device Evaluated by Manufacturer?: Yes
• Is the Device Single Use?: No
• Is This a Reprocessed and Reused Single-Use Device?: No
• Type of Device Usage: Unknown
• Patient Sequence Number: 1