• Direct discontinuity of the hemidiaphragm
• Intrathoracic herniation of abdominal contents. The stomach and colon are the most common viscera to herniate on the left side and the liver is the most common viscus to herniate on the right side.
• The collar sign, a waistlike constriction of the herniating hollow viscus at the site of the diaphragmatic tear
• The dependent viscera sign. When a patient with a ruptured diaphragm lies supine at CT examination, the herniated viscera (bowel or solid organs) are no longer supported posteriorly by the injured diaphragm and fall to a dependent position against the posterior ribs.

Computed tomography has an increased accuracy of diagnosis over X-ray,^[1] but no specific findings on a CT scan exist to establish a diagnosis.^[2] Although CT scanning increases chances that diaphragmatic rupture will be diagnosed before surgery, the rate of diagnosis before surgery is still only 31–43.5%.^[1] Another diagnostic method is laparotomy, but this misses diaphragmatic ruptures up to 15% of the time.^[3] Often diaphragmatic injury is discovered during a laparotomy that was undertaken because of another abdominal injury.^[3] Thoracoscopy is more reliable in detecting diaphragmatic tears than laparotomy and is especially useful when chronic diaphragmatic hernia is suspected.^[3]