What wound types require tetanus shots or tetanus immune globulin?

The short version: the wound decides, not the calendar. Deep, dirty, or devitalized tissue needs both the shot and the immune globulin; a clean minor scrape needs neither urgently.

The retrieved records do not contain a single study that tests wound classification against tetanus outcomes. What they do show is which wounds are dangerous for infection generally. Contaminated wounds carried about 8 times the infection risk of clean ones in open fractures [1], and dirty abdominal wounds infected at 68% versus 1.9% for clean [2]. That is the shape of the risk you are weighing.

The rule that follows from the mechanism, stated as general clinical knowledge and not from these records: a wound that is deep, puncture-type, contaminated with soil or feces, crushed, or has dead tissue gives tetanus spores the oxygen-poor environment they need. Those get vaccine plus immune globulin if your status is uncertain. A shallow, clean, well-bleeding wound does not.

The evidence here is about wound infection risk, not tetanus specifically [1][2]. No record measures tetanus outcomes by wound type.

My call: for a dirty or deep wound, get both the booster and the immune globulin; for a clean minor wound, the shot can wait for your next routine visit. Confidence: moderate on the wound classification, low on the tetanus-specific numbers, because the studies that would settle it are not in front of me.