Detailed Notes on Lisfranc Injuries

Lisfranc Injuries

Case Overview

  • Patient in their 50s with a suspected Lisfranc injury.
  • Significant fractures involving nearly every cuneiform and metatarsal base.

Anatomy Review

  • Axial projection shows tarsal bones and metatarsal bases.
  • Normal recessed appearance of the second metatarsal assists in midfoot stability.
  • Lisfranc ligament components:
    • Dorsal
    • Proper (interosseous)
    • Plantar
  • Lisfranc ligament connects C1 (medial cuneiform) to M2 (base of the second metatarsal).

Ligament Assessment

  • Dorsal Component:
    • Normally connects C1 to M2.
    • In this case, the ligament does not reach the base of M2.
  • Proper (Interosseous) Component:
    • Fracture at the base of the second metatarsal, which is a strong indicator of Lisfranc injury.
    • Ligament replaced by blood and debris.
  • Plantar Component:
    • C1M2 plantar ligament is present but appears as a stump.
    • C1M3 plantar ligament also injured, stopping before reaching M3.
    • Gray appearance due to blood accumulation.
  • All three components (dorsal, middle, and plantar) are injured.

Classification Systems

Quenu and Kuss Classification
  • Based on the movement of bones relative to each other.
    • Homolateral: All five metatarsals shift to one side relative to the cuneiforms.
    • Divergent: The first metatarsal goes medial, and the other columns go lateral.
    • Isolated: One or two metatarsals shift relative to the cuneiforms.
Vertulo Classification
  • Three-stage system incorporating radiography.
  • Combines well with the Quenu and Kuss system for comprehensive diagnosis.
    • Stage One:
      • Low-grade sprain of the Lisfranc ligament and dorsal capsular tear.
      • Joint is stable.
      • Radiographic examination is usually negative (no displacement or widening).
      • Weight-bearing may not show separation.
      • Scintigraphically "hot" around the second TMT joint.
    • Stage Two:
      • 2−52-5 mm of diastasis on radiography.
      • Loss of arch height.
    • Stage Three:
      • Greater than 55 mm of diastasis between the base of the second metatarsal and the cuneiform.
      • Fallen arch; metatarsal bases drop in plantar position.

Case Assessment Using Vertulo Classification

  • Base of the third metatarsal is sagging, indicating a fallen arch (Stage Three).
  • Measurement between the base of the second metatarsal and the cuneiform is approximately 55 mm, confirming Stage Three.
  • Subtle offset between metatarsals and cuneiforms.
  • Alignment of the fourth metatarsal relative to the cuboid is off.

Additional Diagnostic Signs

  • Fleck Sign: Small chip fracture at the base of M2 or C1 (radiographic or CT finding).
  • Alignment Changes: Not always reliable as they may not always be present.
  • Columnar Anatomy:
    • Medial column: First metatarsal and its cuneiform.
    • Middle column: Second and third metatarsals with their cuneiforms.
    • Lateral column: Fourth and fifth metatarsals with their cuneiforms.
  • Arch Configuration: Assessed on CT and MRI.
    • Abnormal arch with bones sagging into a plantar position.
  • Angle Measurements:
    • Plantar surface of C1 is dorsal to the plantar aspect of M5.
    • Tarsal metatarsal angle less than 1515 degrees.

Most Reliable Indicator

  • Malalignment of the second TMT with lateral displacement of the base of M2 with respect to C2.
  • Second metatarsal not aligned with the cuneiform.
  • In this case, it is a Vertulo Stage Three Lisfranc fracture-dislocation/subluxation with multiple injuries.