MAUDE Adverse Event Report: STRYKER SPINE-US OASYS POLYAXIAL SCREW CANCELLOUS DIA 3.5 X 14; POSTERIOR CERVICAL SCREW SYSTEM

Model Number	48557314
Medical Device Problem Code	Material Separation (1562)
Health Effect - Clinical Code	No Clinical Signs, Symptoms or Conditions (4582)
Date of Event	10/22/2020
Type of Reportable Event	Malfunction
Event or Problem Description
It was reported that during screw adjustment, the "head" of an oasys polyaxial cancellous screw "fell off" intra-operatively.Surgery was successfully completed with another screw and a 20 minute delay.No adverse consequences or medical intervention were reported.
Additional Manufacturer Narrative
Visual inspection: the screw was returned in 2 pieces with the tulip disengaged from the shank.There was deformation on the bottom of the tulip and on the screw shank in the direction the tulip popped off the shank.There was a deep witness mark on the top of the tulip, likely from the tulip adjuster.Device and complaint history records were reviewed for this lot, and no relevant manufacturing issues or similar complaints were identified.Per surgical technique: to minimize the potential for rigid locking and limiting the range of angulation, do not seat the screw head too tightly to the bone.Should the screw head become locked to the bone screw, use the screw head adjuster to break the lock.If needed, the screw may be backed out about half a turn to allow for the head to move freely.If it becomes necessary to remove a screw, begin by unthreading the bone screw with the hex portion of the polyaxial screwdriver, and then reattach the outer sleeve to complete the removal.For additional height adjustments to the screw, the poly adjustment driver can be used in place of the polyaxial screwdriver.This instrument has the same internal hex as the polyaxial screwdriver, but has no sleeve to impede vision.It was reported that the screw tulip disengaged during tulip adjustment.The screw was implanted with no issues as per the surgical technique with the oasys screwdriver.All broken fragments were retrieved.The angle was not difficult and the surgeon did not appear to apply excessive force.Deformation on the screw shows that the tulip disengaged in one direction and there was a deep witness mark present on the top of the shank, showing a significant downward force applied.Most likely cause due to overangulation or excessive force applied during tulip adjustment.
Event or Problem Description
It was reported that during screw adjustment, the "head" of an oasys polyaxial cancellous screw "fell off" intra-operatively.Surgery was successfully completed with another screw and a 20 minute delay.No adverse consequences or medical intervention were reported.

• Brand Name: OASYS POLYAXIAL SCREW CANCELLOUS DIA 3.5 X 14
• Common Device Name: POSTERIOR CERVICAL SCREW SYSTEM
• Manufacturer (Section D): STRYKER SPINE-US; 2 pearl court; allendale NJ 07401
• MDR Report Key: 10868015
• Report Number: 0009617544-2020-00196
• Device Sequence Number: 3803119
• Product Code: NKG
• UDI-Device Identifier: 04546540596161
• UDI-Public: 04546540596161
• Combination Product (Y/N): N
• Initial Reporter Country: CH
• PMA/510(K) Number: K151755
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Reporter Type: Manufacturer
• Report Source: company representative
• Initial Reporter Occupation: Other
• Type of Report: Initial,Followup
• Report Date (Section B): 02/25/2021

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
• Operator of Device: Health Professional
• Device Model Number: 48557314
• Device Catalogue Number: 48557314
• Device Lot Number: 198643
• Was Device Available for Evaluation?: Device Returned to Manufacturer
• Date Returned to Manufacturer: 11/20/2020
• Initial Date Received by Manufacturer: 10/23/2020
• Supplement Date Received by Manufacturer: 01/29/2021
• Initial Report FDA Received Date: 11/19/2020
• Supplement Report FDA Received Date: 02/25/2021
• Is This a Single-Use Device that was Reprocessed and Reused on a Patient? (Y/N): No
• Patient Sequence Number: 1