Anatomic Predisposition to Ligamentous Lisfranc Injury: A Matched Case-Control Study

SLR- February 2014- Romina Vincenti

Reference: Gallagher SM et al. Anatomic Predisposition to Ligamentous Lisfranc Injury: A Matched Case-Control Study.The Journal of Bone and Joint Surgery.2013; 95: 2043-7.

 

Scientific Literature Review

Reviewed by: Romina Vincenti, DPM
Residency Program: Cedars-Sinai Medical Center, Los Angeles, CA
 

Podiatric Relevance: Lisfranc injuries occur in 1 of 50,000 to 55,000 people per year in the United States, either purely ligamentous or in conjunction with avulsed bone components. Subtle purely ligamentous Lisfranc injuries are sometimes missed on initial evaluation. The Lisfranc joint is very complex due to the “keystone” wedging architecture of the base of the second metatarsal that extends farthest proximally into the cuneiform compared to the others. Studies had shown that greater second metatarsal length relative to the depth of the mortise by the cuneiforms were found in patients with Lisfranc injuries. Additional studies were needed to find morphometric characteristics that may predispose a patient to Lisfranc injuries. The hypothesis was that a shorter second metatarsal relative to foot length, narrower calcaneal pitch angle, and cuboid-navicular bone overlap relative to cuboid vertical height may predispose to ligamentous Lisfranc injury.

Methods: The authors performed a retrospective matched case-control study of patients with ligamentous Lisfranc injuries versus a control group without a Lisfranc injury. They matched Lisfranc injury patients in a 1:2 ratio with two control patients. Clinical and radiographic data was used to compare the differences of both groups focusing on second metatarsal length relative to foot length, first intermetatarsal angle, navicular-cuboid overlap relative to cuboid vertical height, first metatarsal-talus angle, and calcaneal pitch angle.
 

Results: The ratio between the second metatarsal length and overall foot length was significantly associated with injury status. It was found to have a significantly smaller ratio of second metatarsal length(p<0.001) on weight-bearing images. No other significant relationship was found.

Conclusions: Patients with a ligamentous Lisfranc injury were found to have a significantly smaller ratio of second metatarsal length to foot length on weightbearing images; in other words a shorter second metatarsal. This may imply that the injury is associated with greater torsional forces transferred along the length of the foot through the second metatarsal to create the ligamentous Lisfranc injury.