From the Guidelines
Yes, it is reasonable to order an X-ray of the ankle after 9 days if symptoms persist, as the Ottawa Ankle Rules suggest that X-rays are indicated when there is pain in the malleolar zone along with either inability to bear weight immediately after the injury and for four steps during assessment, or bone tenderness at specific locations such as the posterior edge of either malleolus 1. If your ankle pain continues for more than a week despite rest, ice, compression, and elevation (RICE protocol), an X-ray can help rule out fractures that might have been initially missed.
The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel 1. These guidelines define best practices for imaging evaluation for several variants of patients presenting with acute ankle trauma.
Some key points to consider when ordering an X-ray of the ankle include:
- The Ottawa Ankle Rules are validated in children >5 years of age and should not be used in patients meeting the exclusionary criteria listed above 1
- Typical radiographic protocols should include three standard views: anteroposterior, lateral, and mortise views to include the base of the fifth metatarsal bone distal to the tuberosity 1
- Weight-bearing radiographs, if possible, provide important information, particularly with fractures of uncertain stability 1
While many ankle injuries are sprains that heal with conservative management, persistent pain could indicate a fracture, especially if you're experiencing significant swelling, bruising, or inability to bear weight. The timing of 9 days is appropriate because it allows sufficient time for minor sprains to show improvement while not delaying diagnosis of more serious injuries that require specific treatment. If the X-ray is negative but symptoms continue, further imaging such as an MRI might be considered to evaluate soft tissue injuries.
From the Research
Ankle X-ray After 9 Days
- The decision to order an X-ray of the ankle after 9 days if symptoms persist can be guided by clinical prediction rules such as the Ottawa Ankle Rules (OAR) or the Low Risk Ankle Rule (LRAR) 2, 3.
- These rules help clinicians determine the need for radiography in ankle injuries, reducing unnecessary X-rays without missing clinically significant fractures.
- A study on the introduction of the LRAR into a pediatric emergency department found that it safely and effectively reduced the rate of radiography in ankle injuries by 47.3% without missing any clinically significant fractures 2.
- The OAR, when modified, can also reduce the number of X-ray studies requested by 28% while maintaining a high sensitivity for detecting fractures 3.
Considerations for X-ray Timing
- There is no specific evidence to suggest that waiting 9 days to order an X-ray is unreasonable, as the decision to order an X-ray should be based on clinical judgment and the presence of specific criteria outlined in rules like the OAR or LRAR.
- A study on ankle injury manipulation before or after X-ray found that performing X-rays before manipulation may constitute best practice, as it provides a better assessment of fracture configuration and guides initial reduction 4.
- However, this study does not directly address the timing of X-ray orders in relation to the duration of symptoms.
Clinical Judgment and Guidelines
- Clinical judgment, combined with adherence to guidelines like the OAR or LRAR, is crucial in determining the appropriateness of ordering an X-ray for ankle injuries 2, 3, 5.
- These guidelines can help reduce unnecessary radiography while ensuring that patients with significant fractures are properly diagnosed and treated.