|
On (b)(6) 2025, a patient underwent spinal surgery consisting of seaspine's admiral acp system.During the procedure a temporary fixation pin (ap2100506) was placed into the lower screw hole of the plate.Screws were placed into all other screw holes.Upon removal of the temporary fixation pin it was observed that a significant portion of the pin had broken and remained in bone.The reporter noted that the broken fragment was not retrieved from the surgical site.A new trajectory was drilled and a shortened screw was placed.The reporter noted that no observable injury resulted from the broken fixation pin, however the broken fragment remains in the bone.
|
|
Inspection of the returned fixation pin showed it fractured about 2.5 mm from the screw head.Microscopic examination revealed material compression on one side of the fracture surface, indicating the pin failed under significant bending loads.This suggests the pin likely broke during screw deployment rather than during initial placement or plate positioning.The pin was reportedly placed in an inferior screw hole, and inserting superior screws first could have increased bending stress on the inferior pin.There was no indication the surgeon had difficulty maintaining plate position, further supporting that the fracture occurred after one or more screws were already deployed.Because the break was only noticed at the end of the procedure, multiple screws may have been placed before the fracture occurred.An additional contributing factor may have been hyper-angulated insertion of the fixation pin.While using the screw hole can improve plate stabilization, it also increases trajectory variability, and excessive angulation could have amplified bending moments on the pin, leading to fracture.Review of qf-10-01 admiral acp system ifu: possible adverse events, bending, disassembly, or fracture of components.
|