Device evaluation: upon return, visual inspection of the nail revealed the junction site of the male and female components between the screws and screw holes of the nail had visible evidence of discoloration.Utilizing external assessments and standard corrosion test methods (salt spray), our investigation has identified mechanically assisted crevice corrosion (macc) as the likely direct cause.The key element has been the mechanical micro-movement within the anti-rotation junction of the stryde devices due to the higher weight bearing potential as a result of a more mobile patient population.We have been able to replicate this in-vitro and have developed the mechanical parameters that drive the clinical variation in corrosion.In-vitro testing has shown a correlation between the load on the telescopic junction of the device and the degree of corrosion, with much less corrosion seen at lower loads.This helps explain why different levels of corrosion between patients as weight bearing protocols vary among surgeons.A root cause analysis was performed and found the risks associated with mechanically assisted crevice corrosion (macc) were not adequately identified and mitigated through the risk management/design control process.Device records review: review of the device history records indicated the precice-stryde nail was visually inspected,functionally tested, and met all required specifications prior to release.
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