Accuracy of Ottawa ankle rules to exclude fractures of the ankle and mid-foot

The exact number of ankle sprains that occur during sports activities and are treated by non-professionals is uncertain. However, these injuries are common and are frequently seen by general practitioners. When people injure their ankles, they often go to the emergency department, where X-rays are commonly done. Surprisingly, fewer than 15% of these cases show ankle or mid-foot fractures. This low rate led to the development of the Ottawa ankle rules back in 1992. These rules are a set of questions and assessments used to determine if an ankle or foot fracture is likely.

To assess the ankle, the rules include checking if the person can walk four steps without difficulty and noting any tenderness at specific spots around the ankle bones. For the mid-foot, it involves checking for the ability to walk normally and any tenderness at particular points on the foot. These rules are designed to quickly rule out fractures, and they have been tested and refined in various medical settings to ensure their accuracy.

When most patients who hurt their ankles go to the emergency room, they often get X-rays done. Even if the accuracy isn’t perfect, having a test that’s very sensitive can still help cut down on the number of X-rays needed. So, the Ottawa ankle rules focus more on being sensitive (catching as many potential fractures as possible) rather than being super specific (only catching fractures and nothing else). We did a detailed review to see how well these rules work in practice.

Studies that used the Ottawa ankle rules to check for ankle or mid-foot fractures were identified. Various databases such as Medline, Embase, CINAHL, and the Cochrane Library were searched without any language restrictions. Additional resources like the Science Citation Index were also explored.

The Ottawa ankle rules help doctors decide if a patient with a recent ankle injury needs an X-ray to check for a fracture. In most cases, less than 2% of patients who were negative for a fracture according to the Ottawa ankle rules actually had one.

These rules are designed to be very sensitive, meaning they’re good at catching potential fractures. We were especially interested in how well they rule out fractures. However, we also looked at specificity, which tells us how many unnecessary X-rays might be avoided. It’s surprising that specificity varied so much, ranging from 10% to 79%.

Differences in doctors’ skills, how they interpret the test, and their experience can affect how accurate the Ottawa ankle rules are. Some studies mentioned details about the doctors who performed the test, like how long they’ve worked in emergency departments. Also, how patients express pain might vary culturally, which could lead to more false positives or negatives.

While the Ottawa ankle rules aim to reduce unnecessary X-rays, the economic impact is complex. For the test to save costs, doctors need to use it in their practice. One study found that while doctors recognized the usefulness of the test, they didn’t change their behavior much. Doctors want to avoid missing fractures, so they focus on sensitivity, even if it means more unnecessary X-rays. Concerns about their professional reputation or facing lawsuits might explain this. On the other hand, insurers want a balance between sensitivity and specificity to save costs.

Quick access to X-rays might also lead to more requests for them. So far, we haven’t looked at how useful the Ottawa ankle rules are for doctors in primary care settings. It might be useful to spread awareness about these rules among general practitioners and those involved in sports activities.

 

Conclusion

The evidence strongly backs the Ottawa ankle rules as a reliable tool for ruling out fractures in the ankle and mid-foot. It boasts a sensitivity of nearly 100% and a reasonable specificity. Utilizing these rules should lead to a significant decrease, by about 30-40%, in the number of unnecessary X-rays needed.

A seasoned orthopedic surgeon and foot and ankle specialist, Dr. Mohammad Athar welcomes patients at the offices of Complete Orthopedics in Queens / Long Island. Fellowship trained in both hip and knee reconstruction, Dr. Athar has extensive expertise in both total hip replacements and total knee replacements for arthritis of the hip and knee, respectively. As an orthopedic surgeon, he also performs surgery to treat meniscal tears, cartilage injuries, and fractures. He is certified for robotics assisted hip and knee replacements, and well versed in cutting-edge cartilage replacement techniques.
In addition, Dr. Athar is a fellowship-trained foot and ankle specialist, which has allowed him to accrue a vast experience in foot and ankle surgery, including ankle replacement, new cartilage replacement techniques, and minimally invasive foot surgery. In this role, he performs surgery to treat ankle arthritis, foot deformity, bunions, diabetic foot complications, toe deformity, and fractures of the lower extremities. Dr. Athar is adept at non-surgical treatment of musculoskeletal conditions in the upper and lower extremities such as braces, medication, orthotics, or injections to treat the above-mentioned conditions.