Broken ribs are common after trauma and X-rays are frequently used to diagnose them. Sometimes they can be seen on a chest X-ray but rib X-rays are better because they are dedicated to the ribs. Rib fractures which are not separated can be hard to see on X-rays and can be missed. A CT scan of the chest is the best test and gives the most detail of the ribs.
By themselves rib fractures are rarely of consequence other then the pain they cause. They can however cause complications. The most significant is a pneumothorax or air outside in the pleural space pushing on it. This will often be diagnosed on the X-rays ordered for diagnosing the rib fracture.
Other complications include injury to blood vessels for fractures of the upper ribs. Injury of the abdominal organs when the rib fractures are low. This would include injuries to the liver, spleen and kidney. Injury to the lung can occur such as a tear, bruising or herniation of the lung. Pneumonia can develop from shallow breathing do to pain from the rib fractures.
The cause in most cases is trauma such as that from an accident. Other causes can be from a cancerous lesion weakening the bone. Patients who are getting radiation treatments to the chest can suffer from rib fractures. Rib fractures can also occur after coughing spells.
Rib fractures are frequently evaluated with X-rays. Chest X-rays are often ordered but a rib X-ray series is best. Despite this, a significant portion of rib fractures can be missed, especially those which are not separated. A CT scan is better to look for rib fractures. Given that the treatment is most commonly supportive, it is not crucial to make the diagnosis, once complications such as pneumothorax and organ injury are ruled out.