What are the real risks of spinal fusion surgery? The surgeon told me all the possible things that could happen (I know they have to do this) but I’d like to get a handle on what’s really likely and how likely. Can you offer me any additional information to shed light on this subject?

Surgeons don’t perform spinal surgery on just anyone without a strong chance that the procedure will help the patient. Possible complications are always considered ahead of time. And if a patient has too many risks, surgery may not be advised. In a recent study from the University of Washington in Seattle, surgeons explored the various risks for medical complications after spine surgery. The information they presented may help you.

In this study, they used national databases of information (e.g., Medicare, Worker’s Compensation, National Inpatient Sample) collected on thousands of patients. The amount of data collected in studies like this can be very helpful. Demographic factors such as age; gender; use of tobacco, alcohol, or other drugs; and diagnosis can be factored in. Body mass index (an indication of obesity), presence of other health problems (e.g., diabetes, high blood pressure, heart disease, history of cancer) can also be considered.

In this study, they also looked at area of the spine operated on (cervical, thoracic, lumbar, sacral) and the underlying pathology (degenerative, trauma, tumor, infection, fracture). The surgical approach (anterior, posterior, combined) was also recorded and compared with the number and type of complications after surgery. All patients were followed for at least two years after the first spinal surgery.

The most common problem after spinal surgery was pulmonary complications (e.g., acute respiratory distress syndrome, pneumonia). This was followed by hematologic complications (e.g., blood loss requiring transfusion, blood clots), urologic problems (e.g., urinary tract infections), and cardiac complications (heart attack, arrhythmias, heart failure).

Other problems involving the gastrointestinal (GI) system or neurologic complications though less common were also reported. GI bleeding, colitis, or ascites (fluid in the abdomen) were the most common adverse events. Neurologic problems stemmed most commonly from strokes, delirium, electrolyte imbalances, and seizures.

After gathering and analyzing all the data, they found the two strongest risk factors for complications after spinal surgery were age (older than 65) and extent of surgery (invasiveness). Surgical invasiveness refers to the number of spinal levels involved, the amount of hardware used, and the approach (anterior, posterior, both). A special scoring system was used to calculate level of invasiveness for each procedure.

Two other risk factors affecting almost all the body systems were hypertension (high blood pressure) and anemia. History of diabetes, heart disease, and thoracic surgery were major risk factors affecting four of the six major organ systems included in this study. Patients who had cardiac or pulmonary complications were four to 10 times more likely to die during the first two years after surgery.

That last statistic sounds pretty grim. The actual number of patients who die from complications after spinal surgery is pretty low. The best thing to do is to sit down with your surgeon and review your specific risk factors. The decision to have surgery, the type of surgery, and the invasiveness of the procedure can be influenced in part by considering potential complications but also looking at the likelihood that you would be at risk for any of those problems.