Manufacturing and inspection records for right 14 hole locking lateral plate (part number pl-lel14r, batch number 569421) was reviewed, and no anomalies were found.The returned plate was examined with magnified photography.All three unthreaded holes towards the most distal end of the plate had experienced varying degrees of damage.The two least-distal holes had only mild/light anodization wear within the holes.The most distal hole had extensive damage including scratches, wear, and nicking to counterbore surfaces, in-hole surfaces, and to the edges on the bottom of the plate; this had resulted in significant asymmetric deformation to the most distal hole.The distalmost holes of the plate were measured.The hole relevant to the reported event was the distalmost distal hole.The distalmost distal hole measurement did not meet specifications.A functionality test reproducing the reported event could not be conducted since the reported screw was not returned for evaluation.Additionally, the most distal hole appeared to be damaged in a fashion that has resulted in asymmetric deformation of the hole feature.Specifically, the damage to the top of the hole (i.E.Counterbore/countersink) appeared on one side of the hole, whereas the damage to the bottom of the hole (i.E.Bottom-side plate hole edges) appears on the opposite side of the hole.This may indicate that a screw was inserted off-axis, potentially resulting in damage to the hole.Insertion of a screw off-axis can result in unusual phenomena perceived by the end user.Additionally, the damage done to this plate has resulted in anodization wear.As anodization is one of the final steps performed in the manufacturing process for this device, anodization wear within the hole would likely not have occurred during manufacture and would instead have most likely occurred during usage in the field.It is unclear why or how the distalmost distal hole is larger than the allowable hole size; the noted wear may be one potential reason.This out-of-specification hole is the most damaged hole of the three noted previously, and the damage present appeared to have worn away the anodization coating which is normally applied at the end of the manufacturing process.This would imply the damage that has worn away at the hole, and potentially expanded its diameter, would likely have happened after manufacture.However, based on the information received the root cause could not be determined.
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