This movie tries very hard to be something, but fails.
Reading the plot summary, you might think, that this is yet another Rape & Revenge movie. Having seen it, I can tell you that it is not.
Comparison to Martyrs
That movie actually got my interest as it was compared to Martyrs, a movie of the New French Extreme genre. Turned out, it has nothing in common with Laugier's masterpiece. While Martyrs has a meaning that is transported by the movie and supported by almost every aspect of every scene in the movie, with Trauma it is exactly the opposite. Traumas scenes are mostly intended to be gory, disturbing or simply disgusting but nothing of this feels linked to the main plot. Some other scenes try to be artistic, but they just seem misplaced in this movie.
The plot
Back to the plot: Roja places a lot of interesting puzzle pieces, like the eponymous Trauma that haunts the antagonists. What is the relationship between the four women? Why is it commonly known for the residents and the police (and somehow accepted) that the guys are psychopaths? And many more ... And that is the point that I was completely disapointed with. The plot develops mostly in illogical ways, that puzzle pieces are thrown on the screen but almost never connect to anything. Rojas seems to be overwehelmed by his own attempt to create a compexity that leaves the audience with that mindfuck feeling when everthing connects at the end. However, with Trauma you will be left with a lot of loose ends dangling around and even more "But Why/what about ...? questions.
Movie realization
One aspect about the movie is notable: The special effects are very good. Not much more to say about it without including Spoilers, but give that SFX team a raise!
The camera/screenplay is kind of inconsitent. Soemtimes it matches the brilliance of the effects and sometimes it just feels wrong. Too shaky, cuts away too fast, ...
The actors are trying their best, the german translation/dubbing varies from mediocre to softporn-like.
Conclusion
Those of you who want to see some gory scenes (and nudity) and liked A Serbian Film, take a look. Everyone else, watch something else.