Painful Ankles...to X-Ray or NOT?

Image: http://www.bmj.com/content/326/7386/417

This month I am talking a bit about bone fractures and x-rays. As we try to "do no harm" in medicine, leading physician groups have been taking a closer look at procedures that have become automatic, and determine whether or not they are medically necessary- do they IMPROVE outcomes? One such procedure involves imaging ankle injuries. Both clinicians and patients often expect that a painful joint needs an x-ray as part of a thorough evaluation. When SHOULD we order an x-ray for a painful ankle? Current evidence suggests the answer to that question- at least for adults- lies in the "Ottawa Rules", a guideline to help clinicians decide whether or not a fracture is truly likely, and therefore, whether or not to order an x-ray.

First, questions for the patient:
When the injury happened- could you bear weight immediately? 
Could you bear weight when you reached the medical facility? 
                     If the answer to both of these is YES- you could definitely bear weight and walk on the ankle- it is less likely to be fractured.

Then, questions for the doctor as she examines your ankle: 
Is there pain at the bottom, back edge of your ankle bones, both on the inside and the outside? (in medical terms, the distal 6 cm, posterior edge or tip of the lateral or medial malleolus).
Is there tenderness at two different spots on your foot (the navicular and 5th metatarsal bones)? 

The majority of ankle injuries are sprains, not fractures, which involves the ligaments attaching the bones to each other- not the bones themselves. As such, x-rays will not "show" ankle sprains- they are diagnosed by clinical exam. Ankle sprains can be very serious injuries that require splinting or even casting, but they do NOT necessarily require imaging with x-rays.

BOTTOM LINE: Not all ankle injuries need to be x-rayed; an open conversation with your physician about utilizing the Ottawa Rules may save you some unnecessary radiation and expense.