2015 ISAKOS Biennial Congress ePoster #1124
Anatomical and Radiological Correlation of the Knee Anterolateral Ligament
Camilo P. Helito, MD, PhD, Prof, São Paulo, SP BRAZIL
Paulo Helito, MD, São Paulo, SP BRAZIL
Hugo Costa, MD, São Paulo BRAZIL
Marcelo B. Bonadio, MD, São Paulo, SP BRAZIL
Luís Eduardo P. Tírico, MD, São Paulo, SP BRAZIL
Riccardo Gomes Gobbi, MD, PhD, São Paulo, SP BRAZIL
Fabio J. Angelini, MD, Sao Paulo, SP BRAZIL
Marcelo Bordalo-Rodrigues, MD, São Paulo BRAZIL
Roberto Freire da Mota e Albuquerque, MD, PhD, São Paulo, SP BRAZIL
José R. Pécora, Prof., São Paulo, SP BRAZIL
Gilberto L. Camanho, MD, São Paulo, SP BRAZIL
Marco K. Demange, MD, PhD, São Paulo, SP BRAZIL
Institute of Orthopedics and Traumatology, University of São Paulo, São Paulo, Brazil, São Paulo, São Paulo, BRAZIL
FDA Status Not Applicable
Summary: MRI findings are compatible to anatomical dissection findings of the Knee Anterolateral Ligament, validating this method as a diagnostic tool of this structure
Abstract:
Introduction
Recent anatomical studies clearly delimited landmarks of origin and insertion as well as the path and characteristics of the knee anterolateral ligament (ALL).
All existing MRI studies of this structure, either in healthy or individuals with ACL injury, are in a theoretical field that the evaluated structure corresponds to the ALL. No study that we are aware of so far held anatomical-radiological correlation, demonstrating that the structure characterized is in fact the ALL. This characterization is important since there are several structures that can overlap and confuse in the studied region. Thus, the objective of this study is to establish an anatomical-radiological correlation of the ALL through MRI studies and dissection in cadaver knees, validating this method for the evaluation of ligament.
Methods
We performed a prospective study with 13 cadaver knees. All cadavers were subjected to MRI and subsequently to anatomical dissection. The MRIs following parameters were evaluated: distance from the origin of the ALL to the origin of the LCL, distance from the origin of the ALL in relation to its bifurcation point, maximum length of ALL (distance from its origin to the tibial insertion), distance from the tibial insertion to the articular surface of the tibia, thickness and maximum width. After the MRIs, cadavers were dissected following dissection protocol already established in literature. After the isolation of the ALL, the same measurements performed in the MRIs were done.
The two measurements were statistically analyzed by SPSS 20.0 software. We performed the intraclass correlation coefficients (ICC) with confidence intervals of 95% and a repeatability measure to assess the error between the methods.
In addition, Bland-Altman tests to assess any tendency among the evaluated methods were analyzed.
Results
The ALL was clearly visualized in all thirteen dissected knees, as was seen in its entire course in all MRIs performed.
Evaluating the correlation between the anatomic findings and the MRI, the ICC was greater than 0.8 (corresponding to excellent correlation) for all variables, except thickness and width that showed correlation values of 0.56 and 0.25, respectively. The highest correlation was found for the length of the ligament (0.925).
Despite the high correlation, the measure of the ALL length was the only that presented repeatability (corresponding estimation error) greater than 1mm. All other variables presented minimum error (less than 1mm), even thickness and width variables that did not show good correlation between the measurements. The estimation error between the methods for thickness was 0.34mm and for width was 0.39 mm.
According to the analysis of the Bland-Altman plots, the results were that MRI tends to reduce the values of width and thickness of ALL compared to anatomical measurements. The other variables showed no specific pattern of variation.
Conclusion
MRI findings are compatible to anatomical dissection findings of the Knee Anterolateral Ligament, validating this method as a diagnostic tool of this structure