Diagnostic Accuracy of the Ottawa Knee Rule to Rule out Knee Fractures Using MRI as Gold Standard
DOI:
https://doi.org/10.37762/jgmds.13-2.894Keywords:
Ottawa Knee Rule, Knee Fracture, Diagnostic Accuracy, MRI, Emergency Department, Sensitivity, SpecificityAbstract
ABSTRACT
OBJECTIVES
This study aimed to determine the diagnostic accuracy of the Ottawa Knee Rule for detecting knee fractures, using magnetic resonance imaging (MRI) as the reference standard.
METHODOLOGY
This prospective diagnostic accuracy study was conducted at the Department of Emergency Medicine, Lady Reading Hospital, Peshawar, from August 2023 to February 2024. A total of 96 patients with acute knee trauma were included using consecutive non-probability sampling. The Ottawa Knee Rule was applied clinically, followed by MRI evaluation. Diagnostic parameters, including sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), likelihood ratios, and 95% confidence intervals (CI), were calculated.
RESULTS
The Ottawa Knee Rule demonstrated a sensitivity of 86.1% (95% CI: 71.3-94.2) and specificity of 65.0% (95% CI: 51.5-76.6). The PPV was 59.6% (95% CI: 45.3-72.4), while the NPV was 88.6% (95% CI: 75.4-95.4). The overall diagnostic accuracy was 72.9%. The positive likelihood ratio (LR+) was 2.46, and the negative likelihood ratio (LR−) was 0.21.
CONCLUSION
The Ottawa Knee Rule demonstrated good sensitivity and moderate specificity; however, its performance was lower than that reported in meta-analyses. It remains a useful rule-out tool; however, findings should be interpreted cautiously due to limitations in MRI-based validation and study design.
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References
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