MR Imaging Evaluation of the Lisfranc Ligament in Cadaveric Feet and Patients With Acute to Chronic Lisfranc Injury.

Abstract

Magnetic resonance (MR) imaging is known to be useful to demonstrate Lisfranc ligament injury. There are few studies that report differences in MR imaging findings of acute or chronic Lisfranc ligament injuries. We applied oblique MR imaging planes parallel to the Lisfranc ligament for better visualization of the entire course of the ligament and assessed the detailed MR imaging appearances of the Lisfranc ligament in cadavers and patients with presumed Lisfranc injuries. Twelve preserved cadaveric feet were examined using a small-diameter surface coil. Long axis, oblique sagittal, and oblique short axis cross sections parallel to the Lisfranc ligament, dorsal ligament, and plantar ligament were obtained. Twenty-six MR examinations from 23 patients with suspected Lisfranc joint injuries were evaluated. In the cadaveric study, the Lisfranc ligament was satisfactorily visible along its entire course in a single slice on long axis and oblique sagittal MR images. The dorsal ligament and the plantar ligament were visible separately from the Lisfranc ligament in oblique sagittal and oblique short axis planes. In the patient study, 11 MR examinations led to diagnoses of complete tears of the Lisfranc ligament that were acute injuries (3-21 days after trauma) mostly associated with disruption of the dorsal and plantar ligaments. Nine studies led to diagnoses of incomplete tears of the Lisfranc ligament that were chronic injuries (2-14 months after trauma). Recovery of the continuity of the disrupted ligament was observed in 3 patients. MR imaging demonstrated the integrity of the ligaments and was useful for diagnosing an acute Lisfranc injury. Fibrous healing of the torn ligament was observed in a chronic injury.