Usefulness of the oblique coronal plane in ankle MRI of the calcaneofibular ligament

•We evaluated the diagnostic accuracy of oblique coronal MRI of the calcaneofibular ligament.•Anatomic identification of the CFL on orthogonal MR imaging sequences and CFL views was evaluated.•Diagnostic accuracy using orthogonal and CFL views was evaluated by calculating sensitivity, specificity, and accuracy.•CFL view imaging allows better anatomic evaluation and improved sensitivity and accuracy of diagnosis of CFL injury.

AimTo evaluate the usefulness and diagnostic accuracy of oblique coronal MRI of the calcaneofibular ligament (CFL) view for diagnosis of CFL injury.Material and methodsThis retrospective study included 91 patients who were suspected to have CFL injury who underwent CFL view imaging. Anatomical identification of the CFL on orthogonal MRI sequences and CFL views was evaluated. Two radiologists evaluated the CFL based on an entire length view, an entire width view, and margin sharpness using a four-point scale. Diagnostic accuracy using orthogonal and CFL views was evaluated by calculating sensitivity, specificity, and accuracy. Arthroscopic or clinical findings were used as the reference standard.ResultsBoth readers found identification of lesions using the entire length, entire width, and sharp margin from CFL view images to be superior to that based on orthogonal images. The sensitivity and accuracy of diagnosing CFL injury were significantly higher when using the CFL view compared to the orthogonal view, although specificity was not significantly different between the CFL view and orthogonal view images.ConclusionsCFL view imaging enables better anatomical evaluation and improved sensitivity and accuracy of diagnosis of CFL injury. CFL view images should therefore be used to evaluate potential CFL injuries.