Updated fields: d4, d9, g3, g6, h2, h3, h4, h6, h10 mayfield modified skull clamp (a1059) was returned for evaluation.Device history record (dhr): the dhr was reviewed and shows no abnormalities related to the reported failure.Failure analysis -upon investigation of the returned unit, it was noted that the returned unit had only slight movement in the lock, but when properly positioned and put under pressure, it did not move.A residue buildup was present on inspection, and on disassembly, it was noted that the index knob and the lock would need new components added to replace worn internal parts.The unit was also machined to have heli coils added to large starburst threads.Root cause - the complaint of slippage could not be confirmed via inspection and testing of the unit.When properly positioned with pressure applied, the unit performed without failure.The device was cleaned, machined, with routine maintenance performed, and any worn internal components replaced.No further investigation is required based on the acceptability of risk and no adverse trends were identified.This will be monitored and trended going forward.At present, we consider this complaint to be closed.
|