What is your diagnosis?

Minimally displaced fractures of the proximal 2nd, 3rd, and 4th metatarsals (Image 2 green circle) with concern for possible Lisfranc injury (Image 2 red square). 

• Pearl: The Lisfranc complex is a tarsal-metatarsal joint involving the articulation between the 1st and 2nd metatarsals and the medial and middle cuneiforms and their ligamentous stabilizers [1]

• Pearl: The complex is critical to the stability of the midfoot and the arch [1]

Image 2. Annotated image from Image 1. Red box shows the area of concern for LisFranc injury with a green circle highlighting the proximal metatarsal fractures. 

What are the key exam findings?

Patients will typically have significant mid-foot pain diffusely and be unable to bear weight. While not commonly present, plantar ecchymosis over the area of the joint is nearly pathognomonic for a Lisfranc injury. [2]

Image 3. Courtesy of: Orthopaedicsone.com 

What additional imaging can help confirm the diagnosis?

While x-ray is specific for a Lisfranc injury, it is poorly sensitive. Weight-bearing or stress x-rays of the foot are much more sensitive but are difficult in the acute-phase of the injury due to significant pain. CT and MRI are both adequate modalities to evaluate for joint widening with MRI being more sensitive and specific for ligamentous and soft-tissue complex injuries. [3] 

• Pearl: a CT or MRI doesn’t necessarily need to be obtained in the ED for a suspected Lisfranc injury but rather can be obtained as an outpatient with orthopedics/sports medicine appointments. 

What kind of forces cause these injuries?

Typically, high-energy mechanisms such as an MVA are needed but properly directed forces on a plantarflexed foot with sufficient rotational force applied can also cause injury. [4]

• Pearl: Lisfranc injuries can also occur in sports such as football and rugby 

What is your management in the ED? Do I need to consult Orthopedics?

Management in the ED is focused on pain control and immobilization of the midfoot. If the patient has reliable follow-up and can ambulate on crutches, they can be discharged non-weight bearing on that foot with close orthopedic follow-up. As this isn’t a surgical emergency, orthopedics does not necessarily need to be consulted at the time of injury, though they can be helpful in cases where patients do not have easy access to outpatient care.