The reported event could be confirmed, since the holes of the plate are damaged.The device inspection revealed the following: the visual inspection has shown that all holes of the baseplate are damaged, the damage at three of the peripheral screws hole is that strong that the head of the locking screw fell through the hole.The complaint was forwarded to the r&d department for evaluation with following result: the baseplate was most likely implanted using an improper technique.It appears that some of the screw holes may have been damaged by being drilled off-axis, distorting the circular geometry of the locking rib and therefore not allowing the screws to become fully locked into the baseplate rib.Evidence can be seen in the images of both the baseplate and the underside of the glenosphere.When properly installed in the baseplate, the screws will not migrate from their locked positions.There are other circumstances that may cause this scenario such as using power to drive the screws all the way down, improper use of the drill guide, etc." the relevant dimensions of the screw were verified during the investigation and no deviation from the specification could be detected.A review of the device history for the reported lot did not indicate any abnormalities.No corrective actions are required at this time.A review of the labeling did not indicate any abnormalities.No indications of material, manufacturing or design related problems were found during the investigation.Based on investigation, the root cause was attributed to a user related issue.The failure was most likely caused by an improper implantation of the baseplate, this did lead to a damage of the locking holes and therefore the locking threads of the screws could not be locked in the baseplate as required.Due to that the fixation of the screws was unstable and the force was not distributed as designed which finally caused a fatigue failure of the screws.If more information is provided, the case will be reassessed.
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