Any time that a manufacturer of a PMA device modifies that device in a way that affects its safety or effectiveness, the manufacturer must file a PMA “supplement”. We’ve posted before that PMA supplements should be, and generally are, accorded the same preemptive effect as initial PMAs. The other day the Wisconsin Supreme Court agreed. Its discussion of why PMA supplements are every bit as preemptive as initial PMAs is the most thorough we’ve yet seen. If you’re interested in preemption and PMA supplements, you’ll want to read it. Blunt v. Medtronic, Inc., ___ N.W.2d ___, 2009 WL 367768, at *7-11 (Wis. Feb. 17, 2009)