Multibanded anterior talofibular ligaments in normal ankles and sprained ankles using 3D isotropic proton density-weighted fast spin-echo MRI sequence.

OBJECTIVE

The purpose of this study is to evaluate the frequency and MRI characteristics of multibanded anterior talofibular ligaments in normal ankles and to characterize the tear types of multibanded anterior talofibular ligaments in sprained ankles using a 3D isotropic proton density (PD)-weighted fast spin-echo (FSE) MRI sequence.

SUBJECTS AND METHODS

In the first session, 3D PD-weighted FSE MRI of 33 ankles was obtained from 20 asymptomatic volunteers. The number of bands in the anterior talofibular ligaments, the locations of the anterior talofibular ligaments on orthogonal planes of the 3D PD-weighted FSE images, and the signal intensity, depth, and width of each band on their multiplanar reformatted images parallel to the orientation of each band of the anterior talofibular ligament were evaluated by two readers. In the second session, 3D PD-weighted FSE MRI of 51 sprained ankles was evaluated by two readers for determining the number of bands in the anterior talofibular ligaments and the presence of tears in each band.

RESULTS

In the first session, three anterior talofibular ligaments were single banded, 27 were double banded, and three were triple banded. In double-banded anterior talofibular ligaments, the superior band was about two times wider and thicker than the inferior band. The depth, width, and location of single-banded anterior talofibular ligaments and the superior band of double-banded anterior talofibular ligaments were not statistically significantly different. In the second session, the most common type of injury in double-banded anterior talofibular ligaments was a two-band tear.

CONCLUSION

In an evaluation using the 3D PD-weighted FSE sequence, most anterior talofibular ligaments consisted of two bands, and tears in both bands were the most common type of injury in double-banded anterior talofibular ligaments.