Ottawa Ankle Rules: When to Order an Ankle X-Ray
Knowing when to order X-rays, or even what to order, can be confusing. The Ottawa Ankle Rules, developed by Stiell, specifies the criteria to be met before ordering X-rays for a patient presenting with an acute ankle injury.10,11,13,14 The instructions and associated figure below layout these guidelines.
Ottawa Ankle Rules
Using the diagram below we can determine when an ankle series is required. The rule’s reported sensitivity is 1.0, so X-rays are necessary if any of the below are met:
A. There is any pain in the malleolar zone and any of the following:
- Bone tenderness at A
- Bone tenderness at B
- Inability to take 4 steps both immediately and in the emergency department
B. There is any pain in the midfoot zone and any of the following:
- Bone tenderness at C
- Bone tenderness at D
- Inability to take 4 steps both immediately and in the emergency department
If neither of these criteria is present, no imaging is needed.
By knowing these rules and using them correctly, you can:
- Appropriately treat and refer patients
- Keep costs of health care down
- Decrease needless imaging
- Decrease harm to the patient by excess radiation exposure
- Prevent unnecessary interventions
Improved Outcomes
This is just one example of how clinical criteria can help you with your decision to order imaging. Whether it’s the Ottawa Ankle Rules or another clinical decision directive, if you use and understand these rules, you can easily improve your patient outcomes.
- Bachmann LM, Haberzeth S, Steurer J, ter Riet G. The accuracy of the Ottawa knee rule to rule out knee fractures: a systematic review. Ann Intern Med. Jan 20 2004;140(2):121-124.
- Brand DA, Frazier WH, Kohlhepp WC, et al. A protocol for selecting patients with injured extremities who need x-rays. N Engl J Med. Feb 11 1982;306(6):333-339.
- Docherty MA, Schwab RA, Ma OJ. Can elbow extension be used as a test of clinically significant injury? South Med J. May 2002;95(5):539-541.
- Hall FM. The Canadian C-spine rule. N Engl J Med. Apr 1 2004;350(14):1467-1469; author reply 1467-1469.
- Hawley C, Rosenblatt R. Ottawa and Pittsburgh rules for acute knee injuries. J Fam Pract. Oct 1998;47(4):254-255.
- Mower WR, Hoffman J. Comparison of the Canadian C-Spine rule and NEXUS decision instrument in evaluating blunt trauma patients for cervical spine injury. Ann Emerg Med. Apr 2004;43(4):515-517.
- Parvizi J, Wayman J, Kelly P, Moran CG. Combining the clinical signs improves diagnosis of scaphoid fractures. A prospective study with follow-up. J Hand Surg Br. Jun 1998;23(3):324-327.
- Phillips TG, Reibach AM, Slomiany WP. Diagnosis and management of scaphoid fractures. Am Fam Physician. Sep 1 2004;70(5):879-884.
- Springer BA, Arciero RA, Tenuta JJ, Taylor DC. A prospective study of modified Ottawa ankle rules in a military population. Interobserver agreement between physical therapists and orthopaedic surgeons. Am J Sports Med. Nov-Dec 2000;28(6):864-868.
- Stiell I. Ottawa ankle rules. Can Fam Physician. Mar 1996;42:478-480.
- Stiell I, Wells G, Laupacis A, et al. Multicentre trial to introduce the Ottawa ankle rules for use of radiography in acute ankle injuries. Multicentre Ankle Rule Study Group. Bmj. Sep 2 1995;311(7005):594-597.
- Stiell IG, Clement CM, McKnight RD, et al. The Canadian C-spine rule versus the NEXUS low-risk criteria in patients with trauma. N Engl J Med. Dec 25 2003;349(26):2510-2518.
- Stiell IG, Greenberg GH, McKnight RD, et al. Decision rules for the use of radiography in acute ankle injuries. Refinement and prospective validation. Jama. Mar 3 1993;269(9):1127-1132.
- Stiell IG, Greenberg GH, McKnight RD, Wells GA. Ottawa ankle rules for radiography of acute injuries. N Z Med J. Mar 22 1995;108(996):111.
- Stiell IG, Lesiuk H, Wells GA, et al. The Canadian CT Head Rule Study for patients with minor head injury: rationale, objectives, and methodology for phase I (derivation). Ann Emerg Med. Aug 2001;38(2):160-169.
- Stiell IG, Wells GA, Vandemheen KL, et al. The Canadian C-spine rule for radiography in alert and stable trauma patients. Jama. Oct 17 2001;286(15):1841-1848.
- Tandeter HB, Shvartzman P. Acute knee injuries: use of decision rules for selective radiograph ordering. Am Fam Physician. Dec 1999;60(9):2599-2608.
- Wasson JH, Sox HC. Clinical prediction rules. Have they come of age? Jama. Feb 28 1996;275(8):641-642.
