A 21-Year-Old Male with Foot Pain

The Resolution

Differential Diagnosis

• Compartment syndrome
• Cuboid fracture
• Lisfranc fracture dislocation
• Medial cuneiform fracture

Diagnosis
The patient sustained a Lisfranc fracture dislocation. The x-ray reveals misalignment of the second metatarsal tarsal joint with calcification fragments adjacent to the base of the second metatarsal.

Learnings

• Injuries typically result most commonly from a crush injury or motor vehicle accident
• Ligamentous injuries can occur without fracture or gross malalignment, but may result in instability on weightbearing. MRI should be considered even if x-rays are normal
• Appearance typically shows widening at the base of the 1^st and 2^nd metatarsals (or the more lateral proximal metatarsals) >2.5mm
• The most common type is homolateral, as in this case, in which all of the metatarsals are dislocated to the same side
• The “flake sign” (the small fracture fragment adjacent to base of the second metatarsal) is a classic sign for underlying Lisfranc injury
• To avoid missing a Lisfranc injury:
  • Obtain x-rays on all patients with foot pain and swelling
  • If a fracture is seen at the proximal metatarsal, suspect Lisfranc injury
  • If edema persists for 10 days after the injury, suspect Lisfranc injury

Pearls for Initial Management and Considerations for Transfer

• Early diagnosis is essential for maintenance of function
• Initial management in the urgent care setting includes immobilization and instructions for the patient to avoid weight-bearing.
• The decision to treat Lisfranc fracture dislocations surgically vs nonsurgically is controversial
• Patients with a diagnosis of Lisfranc injury should be sent for immediate referral to the emergency department or orthopedist
• Disproportionate pain may be the sentinel indication of a Lisfranc injury. With a negative x-ray and concerning symptoms, splint ‘as if’ there were an injury, then ensure rapid follow up and consider advanced imaging