Long-term Results of Surgery for Calcaneal (Heel) Fractures
Only one per cent of all bone fractures affect the calcaneus (heel bone). But if that's your foot, you'll want to know the results of this study as to what happens years after surgery. Since this injury doesn't happen very often, studying it has been a problem. Small studies have been done but there's always the question of how reliable are the results? If enough small studies are done, it's possible to combine the results into a meta-analysis to compare treatment results.
So far, the results of small studies and one meta-analysis done of those small studies points to better outcomes with surgery. How did those studies define better results? Less pain, better function, fewer cases of disability, greater patient satisfaction, and an earlier return to work. Now, in this study from Duke University Medical Center in North Carolina the long-term results of 157 patients with calcaneal fractures are reported. About half (73) of those patients had surgery. The other half was treated conservatively.
Everyone included in the study was at least 18 years old and had an intraarticular calcaneal fracture. Intra-articular refers to the fact that the fracture extended into and/or affected the joint surface. The fracture was displaced meaning the fracture separated the bones apart. That's why surgery was necessary.
After surgery, everyone was followed for at least five years, some as long as 18 years. The outcomes were measured using three well-known and valid questionnaires to assess pain, function, and severity of disability. Test scores were collected and analyzed from the American Orthopaedic Foot and Ankle Society ankle-hindfoot test, the Foot Function Index, and the calcaneal scoring system. Activity limitations, pain, walking distance, and the use of walking aids are the types of data collected on these tests.
The authors chose these particular tests because the results can be compared from one study to the next. They hope that future studies will be able to compare results against their outcomes to give a clearer picture of what's happening with postoperative calcaneal fractures. In some of the other studies that have been done, researchers used their own scoring system. That makes it more difficult to compare the results to other studies.
In this study, they also keep track of the patient's age when the injury occurred, sex, Worker's Compensation status, and some specific details about the fracture. Worker's Compensation status is a way to track whether or not the injury occurred at work. Previous studies have suggested that patients on Worker's Comp had worse results and were more likely to leave their jobs as a result of the injury. That wasn't the case in this study. Worker's Comp status did not seem to have an influence over the long-term results.
All of the tests were administered over the phone, so the investigators were also able to ask if patients had further treatment (especially surgery) for the foot. About 18 per cent of the 73 operative cases ended up having more surgery beyond the initial surgery to repair the fracture. The reasons for the second operation varied from infection to removal of hardware to ankle fusion for persistent pain. Eighteen per cent might seem high, but other studies report complications as high as 52 per cent. The authors considered their 18 per cent as being fairly low. They attributed this to better understanding of the procedure and improved surgical technique.
In general, the patients in this study had better results than has been reported for patients in other studies. A larger percentage was able to return to work (82 per cent compared to 52 per cent in other studies). Far fewer ended up with an ankle fusion -- three per cent in this study compared with 17 to 22 per cent in other studies. In looking at other studies where patients weren't always treated surgically, the number of patients who went on to have ankle fusion was much higher than for patients who had surgical treatment. That might be an indicator that surgery should be done in more cases that are initially treated conservatively.
The most striking finding of this study was the fact that how the injury occurred (called the mechanism of injury) seemed to make a difference in the final results. Those patients who suffered a broken and displaced calcaneal fracture from a car accident had the worst results. Those who had the same fracture from a fall seemed to do better in the long run.
The authors offer two possible theories for this finding but they are clear to say further study is needed to know for sure. The first possibility is that motor vehicle accidents cause more soft tissue damage along with the fracture. The three questionnaires administered in this study didn't ask any questions about that. The second explanation may be that car accidents are higher-energy accidents compared with falls. The calcaneal fractures might have more bone fragments to heal or there could have been fractures of other bones in the ankle besides the calcaneus.
They may not have been able to explain the differences, but the purpose of the study wasn't to investigate results based on the mechanism of injury. Their goal was to follow patients long-term and see what the overall outcomes were in terms of pain, function, and disability. They accomplished that initial task and suggest that further studies are needed to evaluate these other factors.
Michael Q. Potter, MD, and James A. Nunley, MD. Long-Term Functional Outcomes After Operative Treatment for Intra-Articular Fractures of the Calcaneus. In The Journal of Bone and Joint Surgery. August 2009. Vol. 91-A. No. 8. Pp. 1854-1860.