An event regarding damage (bent and stripped) involving a trident driver shaft was reported.The event was confirmed.Method & results: -device evaluation and results: the universal driver shaft was returned in used condition.The hexalobular tip of screwdriver shaft was bent and stripped.The deformation to the driver indicates the tip was deformed while the device was being used to tighten a screw.Examination of the returned device with material analysis engineer indicated the damage observed is consistent with in-service use.-medical records received and evaluation: not performed as patient factors did not contribute to event.-device history review: review of the device history records indicates devices were manufactured and accepted into final stock with no reported discrepancies.-complaint history review: there has been no other event for the lot referenced.Conclusions: the reported event was confirmed as per visual inspection of the returned device which shows that the hexalobular tip of screwdriver shaft was bent and stripped.The deformation to the driver indicates the tip was deformed while the device was being used to tighten a screw.Examination of the returned device with material analysis engineer indicated the damage observed is consistent with in-service use.A capa was performed an investigation into reports of fractured trident driver tips.The investigation found that the failure mode is observed when the driver is over torqued, the driver tip wears excessively due to repeated use of the driver, or when the driver tip is angulated extremely within the screw head during use.An ecn was implemented on may 6, 2005 to improve the fit of the driver tip and screw head and reduce the likelihood of driver tip deformation.Although the design was improved, the results of the design validation testing indicated that the tip remained susceptible to deformation at extreme angulations of the driver tip within the screw head.The design intent of the driver tip is to deform rather than to deform and/or break the screw (implant).
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