Validation of the Ottawa Ankle Rules in Iran: A prospective survey

Abstract

BackgroundAcute ankle injuries are one of the most common reasons for presenting to emergency departments, but only a small percentage of patients – approximately 15% – have clinically significant fractures. However, these patients are almost always referred for radiography. The Ottawa Ankle Rules (OARs) have been designed to reduce the number of unnecessary radiographs ordered for these patients. The objective of this study was to validate the OARs in the Iranian population.MethodsThis prospective survey was done among 200 patients with acute ankle injury from January 2004 to April 2004 in the Akhtar Orthopedics Hospital Emergency Department. Main outcome measures of this survey were: sensitivity, specificity, positive predictive value, negative predictive value, and likelihood ratios (positive and negative) of the OARs.ResultsSensitivity of the OARs for detecting 37 ankle fractures (23 in the malleolar zone and 14 in the midfoot zone) was 100% for each of the two zones, and 100% for both zones. Specificity of the OARs for detecting fractures was 40.50% for both zones, 40.50% for the malleolar zone, and 56.00% for the midfoot zone. Implementation of the OARs had the potential for reducing radiographs by 33%.ConclusionOARs are very accurate and highly sensitive tools for detecting ankle fractures. Implementation of these rules would lead to significant reduction in the number of radiographs, costs, radiation exposure and waiting times in emergency departments.

Diagnostic accuracy of the Ottawa Ankle and Midfoot Rules: a systematic review with meta-analysis

“…Thirty-four studies (in 33 articles) reported the accuracy of the Ankle Rules,7 19 22 24–27 29 32 35–37 39 44 46 48 49 53 56 60 62 65 67–69 74–77 79 80 82 84 15 studies (in 14 articles) reported the accuracy of the Midfoot Rules7 19 22 25 44 48 53 60 67–69 76 77 84 and for 31 studies it was not possible to distinguish between the ankle and midfoot, so a general Ankle/Midfoot Rules accuracy is provided20 21 23 28 30 31 33 38 40–43 45 47 50–52 54 55 57–59 61 63 66 70 71 73 78 83 85 (table 1 and figures 2 and 3). Pooled estimates of negative likelihood ratios and sensitivity were good, while positive likelihood ratios and specificity were poor.…”

“…The second sensitivity analysis looked at studies in which the entire sample was assessed using medical imaging as the reference standard, and included 25 studies (in 24 articles) for the Ankle,7 19 22 24–27 29 36 37 39 48 53 56 62 65 67 68 74 76 77 79 82 84 12 studies (in 11 articles) for the Midfoot7 19 22 25 48 53 67 68 76 77 84 and 22 studies for the Ankle/Midfoot Rules 20 28 31 33 40 41 45 50–52 54 55 57–59 61 66 70 71 78 83 85. Accuracy estimates were decreased in both sensitivity analyses when compared with the overall accuracies based on all studies (table 1).…”

“…The comparison between Ankle and Midfoot Rules accuracies was based on 15 studies (in 14 articles)7 19 22 25 44 48 53 60 67–69 76 77 84 that evaluated both Rules (figure 4). Bivariate modelling of these data with a covariate for Rules (Ankle vs Midfoot) showed that allowing the variance of the random effects for specificity to differ by Rule provided the best fit (based on the Akaike Information Criterion).…”

Validation of the Ottawa Knee Rule in Iran: a prospective study

“…No studies were found that questioned the generalisablity of the OKR. However, clinical prediction rules may not perform as well when tested in a population other than that in which they were derived 1 12. Therefore, even well-defined decision-making rules are not suitable for application in all clinical settings without validation studies.…”

Effect of Triage Nurse Initiated Radiography Using the Ottawa Ankle Rules on Emergency Department Length of Stay at a Tertiary Centre

“…[1][2][3][4][5] As a result, the OAR have gained widespread acceptance throughout the world. [6][7][8][9][10] Numerous studies have examined nurses' interpretation and application of the OAR. [11][12][13][14] It is clear that the use of the OAR by nurses results in similar diagnostic performance for fracture detection as when the rules are applied by physicians, 15,16 and thus it is believed that emergency nurses can accurately determine which patients require radiographs in the setting of isolated blunt ankle injury.…”