Background
This study aimed to clarify the morphological characteristics of the Lisfranc ligament and the plantar ligament.
Methods
Forty legs from 20 cadavers were examined. Classification proceeded according to the number of fiber bundles in the Lisfranc ligament and the plantar ligament. Morphological features measured were fiber bundle length, width, thickness, and angle.
Results
In Type I-a, the Lisfranc and plantar ligaments were a single fiber bundle; in Type I-b, the Lisfranc ligament was a single fiber bundle, and the plantar ligament was two fiber bundles; in Type II-a, the Lisfranc ligament was a two fiber bundle, and the plantar ligament was a single fiber bundle; in Type II-b, the Lisfranc ligament and the plantar ligament were two fiber bundles; in Type III-a, the Lisfranc ligament was three fiber bundles, and the plantar ligament was a single fiber bundle; in Type III-b, the Lisfranc ligament was three fiber bundles, and the plantar ligament was two fiber bundles; in Type IV, the Lisfranc ligament and the plantar ligament could not be separated. Type I-a was seen in 37.5%, Type I-b in 10%, Type II-a in 30%, Type II-b in 7.5%, Type III-a in 7.5%, Type III-b in 2.5%, and Type IV in 5%. The Lisfranc ligament was significantly larger than the plantar ligament in total fiber bundle width, total fiber bundle thickness, and total fiber bundle angle.
Conclusion
The Lisfranc ligament had three fiber bundles, and the plantar ligament had two fiber bundles; classifications were four types and two subgroups.