What's the Diagnosis? By Dr. Abby Renko

Wed, 08/04/2021 - 1:49pm
Author: 
Abagayle Renko M.D.
Editor: 
Jillian Smith MD

A 55 yo M presents to the ED after a fall.  He is noted to have L foot and ankle pain on exam. An xray is done and shown below. What's the diagnosis? (scroll down for answer) 

 

 

 

Answer: Lisfranc injury

  • In this example, note widening of the space between the 2nd and 3rd metatarsal, plus the fracture at the base of the 2nd metatarsal
  • Lisfranc ligament runs from lateral base of medial cuneiform and medial base 2nd metatarsal
  • Mechanism:
    • varies (plantar flexion w/ axial load, crush or rotational injury)
    • common mechanisms include MVC, football injury
  • Diagnosis:
        • Clinical signs/symptoms:
          • Inability to stand on affected foot
          • Severe midfoot pain
          • Plantar ecchymosis sign: bruise over plantar aspect midfoot
        • Imaging findings: 
          • Gap > 1mm between base of 1st and 2nd OR 2nd and 3rd metatarsals
          • Fracture around lisfranc joint
          • Fleck sign- avulsion fracture of base 2nd MT on medial side 
          • CT imaging may be indicated if high suspicion and XR imaging equivocal 
  • Complications:
        • Chronic pain, early arthritis
        • Dorsalis pedis artery injury
  • Management: Splint/non weight bearing --> emergent ortho referral--> possible surgical repair

 

References:

Omer T, Santiago-Martinez M. Foot Injuries. In: Tintinalli JE, Ma O, Yealy DM, Meckler GD, Stapczynski J, Cline DM, Thomas SH. eds. Tintinalli's Emergency Medicine: A Comprehensive Study Guide, 9e. McGraw Hill.