Comparative analysis of ultrasound and magnetic resonance imaging in diagnosing pain in the posterolateral region of the ankle.

AIM

The purpose of this study was to evaluate the diagnostic value of ultrasound compared to magnetic resonance imaging (MRI) as a reference in detecting peroneus brevis split ruptures.

MATERIAL AND METHODS

We re-reviewed 112 ultrasound examinations performed between 2020 and 2021 by three musculoskeletal radiologists with 8-10 years of experience. Patients were referred due to pain lasting at least 8 months in the posterolateral ankle. Ultrasound was performed using a LOGIQ E9 General Electric device with a 6-15 MHz or 18 MHz probe. Sixty-three patients who underwent MRI within 8 months and were included in the study. Ultrasound and MRI findings were categorized as: a) no peroneus split, b) presence of peroneus split, or c) unspecific findings. MRI served as the reference standard. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were calculated.

RESULTS

Seven cases (11.1%) were false positives (diagnosed on ultrasound but not MRI) and 9 (14.3%) were false negatives (missed by ultrasound but detected on MRI). Six cases (9.5%) were true positives (identified on both ultrasound and MRI), and 41 patients (65.1%) were true negatives (negative on both modalities). Ultrasound showed a sensitivity of 40.0% and specificity of 85.4%. The positive predictive value (PPV) was 46.2%, while the negative predictive value (NPV) was 82.0%.

CONCLUSIONS

Ultrasound demonstrated limited sensitivity but high specificity in detecting peroneus brevis split ruptures.