We generally understand "Lifnei Iver" figuratively, like knowingly giving someone bad business advice, or knowingly serving someone non-Kosher food that they were unaware of.
But what about "Lifnei Iver" mamash? Obviously a terrible thing to do and likely will be over other aveiros, but would a person violate "Lifnei Iver" if they literally put a stumbling block in front of a blind person?