Ankle X-rays in children limited with rule

Using a simple rule can help cut down on X-rays for children with ankle injuries, a Canadian study suggests.

Radiography unnecessary for most children's ankle injuries

Using a simple rule can help cut down on X-rays for children with ankle injuries, a Canadian study suggests.

Radiography is used in 85 per cent to 95 per cent of pediatric injuries but only 12 per cent show fractures, researchers say.

Few sprained ankles need to be X-rayed. (Paul Chiasson/Canadian Press)

"Radiography is unnecessary for most children's ankle injuries, and these high rates of radiography needlessly expose children to radiation and are a questionable use of resources,"  Dr. Kathy Boutis, a pediatric emergency department physician at the Hospital for Sick Children and her co-authors wrote in today's Canadian Medical Association Journal.

When Boutis and her team tested the "Low Risk Ankle Rule" on  2,151 children in Ontario with ankle injuries, they estimated using the rule could potentially reduce the need for radiography by 60 per cent.

Under the rule, an ankle injury is considered low risk depending on where the tenderness and swelling is, such as in certain sprains and strains.

The study included 1,055 children treated under the rule and 1,096 others as controls. They were all between the ages of 3 and 16 years and went to pediatric, community and general hospitals.

"Implementation of the Low Risk Ankle Rule in several different emergency department settings reduced the rate of pediatric ankle radiography significantly and safely, without an accompanying change in physician or patient satisfaction," the study's authors concluded.

They said the rule could apply at emergency departments throughout most of the developed world to reduce unnecessary radiography and use health care resources more efficiently.

A similar rule, called the Ottawa Ankle Rule, already exists for use in adults.

Since the patients weren't randomly assigned to the two groups, it's possible there was bias in the treatment effect, the researchers said.

They also said that doctors participating in the study may have imaged more low-risk injuries out of fear of missing a high-risk injury. Some physicians also preferred the Ottawa Ankle Rule, which results in more frequent recommendations of imaging than the child version. As well, some families preferred radiography.

The study was funded by the Canadian Institutes of Health Research and Physician Services' Incorporated.