Introduction Traumatic diaphragmatic hernias are an unusual presentation of trauma, and are observed in about 10% of diaphragmatic injuries. The diagnosis is often missed because of non-specific clinical signs, and the absence of additional intra-abdominal and thoracic injuries. Case presentation We report a case of a 59-year-old Italian man hospitalized for abdominal pain and vomiting. His medical history included a blunt trauma seven years previously. A chest X-ray showed right diaphragm elevation, and computed tomography revealed that the greater omentum, a portion of the colon and the small intestine had been transposed in the hemithorax through a diaphragm rupture. The patient underwent laparotomy, at which time the colon and small intestine were reduced back into the abdomen and the diaphragm was repaired. Conclusions This was a unusual case of traumatic right-sided diaphragmatic hernia. Diaphragmatic ruptures may be revealed many years after the initial trauma. The suspicion of diaphragmatic rupture in a patient with multiple traumas contributes to early diagnosis. Surgical repair remains the only curative treatment for diaphragmatic hernias. Prosthetic patches may be a good solution when the diaphragmatic defect is severe and too large for primary closure, whereas primary repair remains the gold standard for the closure of small to moderate sized diaphragmatic defects.