AN

Hardcastle Classification of Lisfranc Fractures

Hardcastle Classification of Lisfranc Fractures and Dislocations

  • A difficult classification system that requires practice. However, Lisfranc injuries are high yield (important) and severe, making this classification crucial to learn.
  • The classification ranges from A to C, representing best to worst injury.

Overview of Types

  • Type A: All metatarsals are dislocated.
  • Type B: One or a few metatarsals are dislocated.
  • Type C: Divergent dislocation where metatarsals split down the middle.

Type A: Total Incongruity

  • Characterized by all metatarsals being dislocated.
  • A1: All metatarsals dislocate collaterally.
  • A2: All metatarsals dislocate medially.

Type B: Partial Incongruity

  • Characterized by partial metatarsal dislocations.
  • B1: Partial medial displacement of the first metatarsal, with or without involvement of some (but not all) of the lesser metatarsals (second through fourth).
  • B2: Partial lateral displacement of one or more of the lesser metatarsals (second through fourth). This does not involve the first metatarsal.

Type C: Divergent

  • Characterized by divergent dislocations.
  • The first metatarsal dislocates medially, and some or all of the lesser metatarsals dislocate laterally.
  • C1: A few of the lesser metatarsals dislocate laterally (best-case scenario for Type C).
  • C2: All four lesser metatarsals dislocate laterally (worst-case scenario for Type C).

Comparison with Keanu and Cuss Classification

  • The Keanu and Cuss classification is simpler.
  • Start with Keanu and Cuss if asked about Lisfranc classifications.
  • Both classifications are similar but use different terminology:
    • Keanu and Cuss:
      • A: Homolateral
      • B: Isolateral
      • C: Divergent
    • Hardcastle:
      • A: Total Incongruity
      • B: Partial Incongruity
      • C: Divergent

High Yield Information for Lisfranc Injuries

  • Fleck Sign: A small ossification between the first and second metatarsals.
  • There is no ligamentous connection between the first and second metatarsals.
  • The first metatarsal connects to the middle cuneiform.
  • Lisfranc ligament has three parts: dorsal, middle (interosseous), and plantar.
  • The most common dislocation direction (dorsal or plantar) is dorsal.
  • This occurs because the dorsal ligaments of the tarsal-metatarsal joints are the weakest, causing the metatarsus to often pop up dorsally.