The usual S V U is a crime is investigated (usually a dead body is involved.) It would would also have interaction between the detectives and sometimes Stabler's family would appear.
This was a single story line episode. It starts with a the reporting of the rape, then the taking of the victim's statement and the investigation of rape. Even when the trail goes cold, the storyline strictly stays with rape case. And since the case ends in limbo so does episode.
This was a very special episode that decided to defy the series and to an extent the genre norms to create a compelling episode.