MAUDE Adverse Event Report: STRYKER SPINE-US OASYS 3.5 X 28MM PA SCREW MEDIAL; POSTERIOR CERVICAL SCREW SYSTEM

Model Number	48555328
Medical Device Problem Code	Material Separation (1562)
Health Effect - Clinical Code	Injury (2348)
Date of Event	02/10/2020
Type of Reportable Event	Serious Injury
Additional Manufacturer Narrative
Hospital retained device.
Event or Problem Description
It was reported that an oasys polyaxial screw tulip disengaged on the left side post-operatively.Revision surgery was performed to replace the screw.
Additional Manufacturer Narrative
Visual inspection: the screw was returned with the shank disengaged from the tulip.The tulip was still attached to the rod with a blocker.The blocker did not appear to be overtightened in the tulip.There was deformation on the bottom of one side of the tulip, as well as one side of the shank bulb, indicating the tulip disengaged while angulated in that direction.Device and complaint history records were reviewed and no relevant manufacturing issues or similar complaints were identified.The construct design ending at t1 with c7 being skipped can cause a moment arm at the point of the junction.This may cause additional loading on the bottom most screws.As the bottom most screw was a medial biased screw with directional range of angulation, this additional loading most likely caused the screw to max out its angulation as seen by the deformation on the bottom of the tulip in one direction.This additional loading most likely contributed to the rod slipping on the other side as well.Additionally, other factors such as patient activity level, patient weight and blocker undertightening may have also contributed to the loads put onto the bottom most screws.
Event or Problem Description
It was reported that an oasys polyaxial screw tulip disengaged on the left side post-operatively.Revision surgery was performed to replace the screw.

• Brand Name: OASYS 3.5 X 28MM PA SCREW MEDIAL
• Common Device Name: POSTERIOR CERVICAL SCREW SYSTEM
• Manufacturer (Section D): STRYKER SPINE-US; 2 pearl court; allendale NJ 07401
• MDR Report Key: 9807004
• Report Number: 0009617544-2020-00035
• Device Sequence Number: 2815607
• Product Code: NKG
• UDI-Device Identifier: 04546540469564
• UDI-Public: 04546540469564
• Combination Product (Y/N): N
• Initial Reporter State: FL
• Initial Reporter Country: US
• PMA/510(K) Number: K151755
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Device Implanted Year: 2020
• Device Explanted Year: 2020
• Reporter Type: Manufacturer
• Report Source: health professional
• Initial Reporter Occupation: Physician
• Type of Report: Initial,Followup
• Report Date (Section B): 07/22/2020

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Is this an Adverse Event Report?: Yes
• Is this a Product Problem Report?: Yes
• Operator of Device: Health Professional
• Device Model Number: 48555328
• Device Catalogue Number: 48555328
• Device Lot Number: 13F689
• Was Device Available for Evaluation?: Device Returned to Manufacturer
• Date Returned to Manufacturer: 04/27/2020
• Initial Date Received by Manufacturer: 02/10/2020
• Supplement Date Received by Manufacturer: 06/22/2020
• Initial Report FDA Received Date: 03/09/2020
• Supplement Report FDA Received Date: 07/22/2020
• Is This a Single-Use Device that was Reprocessed and Reused on a Patient? (Y/N): No
• Patient Sequence Number: 1
• Outcome Attributed to Adverse Event: Required Intervention