Comparison of Stress Ultrasonography and Stress Radiography in the Assessment of Multiligament Knee Injury
B.C. Alves, C.B.E. Silva, P.Ê.F. Bezerra, H.M. Pereira, S.A.L. De Souza, J.L.R. De FariaObjectives:
This study aimed to compare the diagnostic efficacy of stress ultrasonography (USG) and stress radiography (RX) in precisely diagnosing multiligament knee injuries, hypothesizing that USG offers comparable diagnostic efficacy to RX while avoiding radiation exposure.
Methods:
An observational, comparative study was conducted with 28 patients awaiting surgical treatment for multiligament knee injuries. Participants underwent both stress USG and stress RX at 0° and 30° of knee flexion. Measurements of articular instability were compared between the injured and contralateral knees. Data analysis included equivalence testing (margin of 1.5 mm), Bland-Altman plots for agreement, and interobserver reliability for both modalities.
Results:
Statistical equivalence was found between USG and RX for mean articular instability measurement, with mean biases close to zero and 90% confidence intervals within the 1.5 mm equivalence margin across all compartments and angulations. However, the analysis revealed moderate agreement between the modalities, with USG showing wider 95% limits of agreement and greater interobserver variability, particularly depending on the examiner's proficiency. Stress radiography demonstrated better interobserver consistency.
Conclusion:
Stress ultrasonography is an effective and safe diagnostic tool for multiligament knee injuries, comparable to stress radiography in assessing instability. Nevertheless, its routine clinical incorporation necessitates further advancements in standardization protocols and specialized training for examiners due to its inherent variability.