Tibiofibular Syndesmotic Ligaments: MR Arthrography in Cadavers with Anatomic Correlation1

Purpose: To use magnetic resonance (MR) imaging and MR arthrography to characterize the normal anatomy of the tibiofibular syndesmotic ligaments with standard and oblique imaging planes in cadavers. Materials and Methods: Ten cadaveric ankle specimens were obtained and used in accordance with institutional and HIPAA guidelines, and informed consent for research was obtained from relatives of the deceased. MR imaging was performed before and after intraarticular administration of contrast material. Proton-density-weighted MR images were correlated with anatomic slices. Results: The anterior inferior tibiofibular ligament (AITFL) had a variable number of bands in all specimens. A separate distal band was identified in all specimens, revealing a more horizontal course than other components of the AITFL and attaching more medially to the anterior margin of the tibial plafond. The posterior inferior tibiofibular ligament (PITFL) and inferior transverse ligament were best seen in coronal oblique planes. The posterior intermalleolar ligament was observed in all specimens and had a variable appearance that ranged from a thin strand to a thick cord. The interosseous ligament (IOL) coursed obliquely to attach proximally to the tibia and insert distally in the fibula. This ligament was fenestrated with separate anterior and posterior fibers. The anterior fibers were more proximal, and the posterior fibers were more distal, attaching to the fibula in close proximity to the PITFL. Coronal images best depicted the course of the IOL. Conclusion: Oblique imaging planes parallel to the long axis of the ligament better display the normal anatomy of the tibiofibular syndesmotic ligaments when compared with standard imaging planes. © RSNA, 2010