Three-dimensional, digital, and gross anatomy of the Lisfranc ligament.

BACKGROUND: There are inconsistencies in the descriptive anatomy of the Lisfranc ligament. No information is available on orientation of fibers or presence of bundles, nor are there 3-dimensional anatomic data on the ligaments or their attachments. This study assessed the 3-dimensional anatomy of the Lisfranc ligament and its attachment sites.

METHODS: A total of 37 cadaver feet were dissected to expose the ligament attachments at the Lisfranc joint. The Lisfranc ligament and plantar ligament attachments were outlined separately and then removed with the attachment outlines preserved. A 3-dimensional digitizer was used to digitize bony and articular surfaces, as well as ligament attachment sites, at approximately 1 mm intervals; the positional accuracy was 0.23 mm. The surface areas of the entire bone, articular regions, and Lisfranc and plantar ligament attachment regions were determined and anatomic details were noted.

RESULTS: The Lisfranc ligament had a single bundle in 73% of the specimens and 2 bundles in 27%. Both variations had a single attachment to the second metatarsal (M2; mean attachment surface area, 135 mm(2)). The single-bundle variation attached to the medial cuneiform (C1; mean attachment surface area, 140 mm(2)). The plantar ligament, C1-M2-M3, attached to the anterior plantar surface of the lateral aspect of C1 (mean attachment surface, 64 mm(2)) and had attachment sites at the bases of M2 and M3. Its fibers ran anteriorly and inferiorly, with attachments to the proximal inferomedial aspect of M2 (mean attachment surface, 63 mm(2)) and fibers extending to a smaller attachment at the plantar aspect of M3 (mean attachment surface area, 26 mm(2)).

CONCLUSION: The Lisfranc ligament is variable in anatomy and can have a single- or double-bundle arrangement. Its area of attachment is larger than that of the plantar ligament.

CLINICAL RELEVANCE: Anatomic descriptions of location, dimensions, and variability in the position and surface area of the ligament attachment sites and of orientation of the bundles provide information for future attempts at repair or reconstruction of the Lisfranc ligament.