On 26 july 2016 the r&d project manager performed a visual inspection of the retrieved items and commented as follows: two polyaxial pedicle screws lot 154331 were returned.One can be engaged normally to the pedicle screwdriver, the second can't.The pedicle screwdriver engages both the torx recess of the screw shaft, and the thread of the screw head (tulip) and fix them in co-axial position.With the defective screw, both the torx recess and the tulip thread are conform, but they cannot be aligned to each other by means of the pedicle screwdriver which therefore cannot be engaged to the tulip.The problem is related to a wrong assembling of the inlay, which is the intermediate component that ensures the mobile coupling of screw shaft and tulip.The tulip, in turns, is secured by a pin.In the normal screw, the inlay is free to move, allowing the poli-axiality.In the defective screw, the inlay is stuck in a position and moreover it can be seen that the pin is not properly inserted but it protrudes from the side.This defect prevents the screw shaft and tulip to be aligned by means of the pedicle screwdriver.Procedures and control methods are in place to guarantee the correct assembling of the pedicle screw.Moreover the second screw of the same lot is free of this defect.No similar event was ever reported.It can be assumed that this defect is a isolated case.Also it has to be noted that the defect doesn't affect the safety of the pedicle screw itself.It prevents the screw to be implanted with the dedicated instrument.The user always have multiple screws available in the or therefore he can open another screw to proceed with the surgery.On 27 july 2016 it was prepared a final report with the information submitted in this report and in the initial one.On 25 august 2016 the report was sent to the initial reporter and the case was closed.
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