What are the treatment strategies for a high energy impact injury to the left foot resulting in multiple non-displaced fractures of the metatarsal bones with a suspected Lisfranc (Lisfranc joint) injury?

Treatment Strategies for High Energy Impact Injury to the Left Foot with Multiple Non-displaced Metatarsal Fractures and Suspected Lisfranc Injury

For a high energy impact injury to the left foot with multiple non-displaced metatarsal fractures and suspected Lisfranc injury, advanced imaging with CT and/or MRI followed by appropriate immobilization with a non-removable knee-high total contact cast or walker is strongly recommended as the initial treatment strategy. 1, 2

Diagnostic Approach

Initial Imaging

1. Standard radiographs should be the first imaging study:

   • Three-view radiographic study (anteroposterior, oblique, and lateral)
   • If Lisfranc injury is suspected, add weightbearing views when possible
   • Comparison views of the contralateral foot can help identify subtle malalignment 1

2. Advanced imaging is necessary when Lisfranc injury is suspected:

   • CT scan is the primary imaging technique for high-energy polytrauma and is essential for:

     • Demonstrating multiple metatarsal and cuneiform fractures
     • Preoperative planning
     • Detecting non-displaced fractures missed on radiographs 1, 2

   • MRI should be considered for:

     • Evaluation of the Lisfranc ligamentous complex
     • Assessment of soft tissue injuries
     • Cases where radiographs are normal but clinical suspicion remains high 1, 3

Clinical Warning Signs

• Midfoot swelling and pain
• Plantar ecchymosis (highly specific for Lisfranc injury)
• Inability to bear weight
• Pain with passive movement of the midfoot 2, 4

Treatment Algorithm

1. For Non-displaced Metatarsal Fractures WITHOUT Lisfranc Injury:

• Conservative treatment with:
  • Non-weightbearing cast for 6 weeks
  • Followed by gradual return to weightbearing 5

2. For Non-displaced Metatarsal Fractures WITH Suspected Lisfranc Injury:

A. Stable Lisfranc Injury (no displacement on weightbearing radiographs):

• Conservative treatment:
  • Non-weightbearing cast immobilization for 6 weeks
  • Followed by protected weightbearing 6, 4

B. Unstable Lisfranc Injury (displacement on imaging):

• Surgical intervention is required with two main objectives:

  • Anatomical reduction
  • Stability of the first three cuneiform-metatarsal joints 2, 4

• Surgical options:

  • Open reduction and internal fixation (ORIF) with transarticular screws
  • Primary arthrodesis with dorsal plate (particularly for purely ligamentous injuries)
  • Combination of techniques based on injury pattern 2, 4

3. Immobilization Recommendations:

• First-line option: Non-removable knee-high total contact cast that immobilizes the foot and ankle 1

• Second-line option: Pre-fabricated knee-high walker rendered irremovable by applying a cast layer or tie wrap 1

• Third-line option: Removable knee-high device (only if non-removable devices are contraindicated or not tolerated) 1

Important Considerations

Potential Complications

• Up to 20% of Lisfranc injuries are missed or diagnosed late, leading to:
  • Post-traumatic osteoarthritis
  • Foot deformities
  • Chronic pain and disability 2, 4

Differences Between High-Energy vs. Low-Energy Lisfranc Injuries

• High-energy injuries (like in this case) typically present with:
  • More concomitant foot fractures (78% vs 4%)
  • More metatarsal base fractures (84% vs 29%)
  • More displaced intra-articular fractures (59% vs 4%)
  • Involvement of more rays (4.1 vs 2.7 on average) 7

Monitoring During Treatment

• Regular clinical and radiographic follow-up to ensure:
  • Proper alignment is maintained
  • No development of skin breakdown (especially with total contact casts)
  • Timely transition to weightbearing 1

Pitfalls to Avoid

1. Delayed diagnosis - maintain high index of suspicion even with normal initial radiographs
2. Inadequate immobilization - failure to use knee-high devices can lead to progressive deformity
3. Premature weightbearing - can disrupt healing and lead to malunion
4. Overlooking associated injuries - high-energy trauma often involves multiple fractures and soft tissue injuries
5. Inadequate patient education - patients need to understand the importance of strict non-weightbearing to prevent long-term complications 1, 2