A 7-year-old girl fell while running. It seemed to be a minor fall, and she was fine immediately after the incident. Ten to 15 minutes later, she began to experience mild abdominal and left anterior chest pain. Breathing difficulty developed, and she was taken to the emergency department. The girl was afebrile with a normal heart rate. Her respiratory rate was 20/min, and she maintained greater than 95% oxygen saturation. A chest examination showed decreased breath sounds on the left and dullness to percussion at the left base of the lung. The abdomen was tender in the epigastric region and was soft and nondistended without guarding or rigidity. Chest and abdominal radiographs showed a gaseous pattern (Figure 1) and coiling of a nasogastric tube (Figure 2) in the left chest.
What is your diagnosis?