In the Dungeon Masters Guide, the Staff of Power and Staff of the Magi have an effect "Retributive Strike":
You can use an action to break the staff over your knee or against a solid surface, performing a retributive strike. The staff is destroyed and releases its remaining magic in an explosion that expands to fill a 30-foot-radius sphere centered on it.
Is there any reason you couldn't use something like a Telekinesis spell or some other elaborately designed trap to break the staff by dropping a boulder or something on it, thereby avoiding the effects of it yourself? I would consider that a solid surface personally.... if you can break it over your knee, a 1,000 pound boulder should do it.