The anterolateral ligament and the deep structures of the iliotibial tract: MRI visibility in the paediatric patient

Abstract

PurposeTo assess the visibility of both the anterolateral ligament (ALL) and the deep structures of the iliotibial tract (ITT) by means of MRI in paediatric patients. To determine reproducibility for such measurements. MethodsKnee MRI data from patients aged <18a without lesions of the capsule or ligaments, fractures, bone edemas, foreign material or motion artifacts were analyzed by two musculoskeletal radiologists separately and twice. The visibility of the different parts of the ALL was determined (femoral, meniscal, tibial parts). Similarly, the visibility of the different parts of the deep ITT was determined: deep attachments of the ITT to the distal femur (insertion near septum, supracondylar insertion and retrograde insertion) and capsulo-osseous layer of the ITT. ResultsWe studied 61 cases (36 female, 25 male). Age was 15 years (±2.3). Interobserver agreement was high. Cohen’s Kappa was 0.864 (95%CI: 0.715–1.000) for the tibial part of the ALL and 1.0 for the femoral part of the ALL. For the deep attachments of the ITT to the distal femur Kappa was 0.828 (95%CI: 0.685–0.971). Regarding intraobserver agreement, Cohen’s Kappa was 1.0 for the femoral part of the ALL and 0.955 (95%CI: 0.867–1.000) for the tibial part of the ALL. For the deep attachments of the ITT to the distal femur Cohen’s Kappa was 0.896 (95%CI: 0.782–1.000). ConclusionOn the basis of our findings it is concluded that the presence of the anterolateral structures of the knee can be determined by MRI in a pediatric population with substantial inter- and intraobserver agreement. This is true for both the ALL and the deep structures of the ITT. Level of evidenceDiagnostic study – Level 3.