What is the treatment for a Lisfranc (Lisfranc joint injury) midfoot fracture?

Treatment of Lisfranc Midfoot Fracture

The standard treatment for unstable Lisfranc injuries involves open reduction and internal fixation (ORIF) or primary arthrodesis, with anatomical reduction being the critical determinant of good long-term outcomes. 1

Diagnosis and Initial Assessment

Imaging Protocol

1. Initial imaging:

   • Three-view radiographic study (anteroposterior, oblique, lateral) 1
   • AP view with 20° craniocaudal angulation for suspected Lisfranc injury 1
   • Comparison with uninjured foot on AP radiographs 1

2. Advanced imaging:

   • CT scan: Essential for preoperative planning and detecting fractures missed on radiographs (25% of midfoot fractures are overlooked on radiographs) 2, 1
   • Weightbearing CT: Most reliable for analyzing the 1st TMT joint and detecting subtle instability 1
   • MRI: Most sensitive for ligamentous injuries and occult fractures 1

Clinical Evaluation

• Check for plantar ecchymosis (highly suggestive of Lisfranc injury) 3
• Test for TMT-1 hypermobility by applying dorsomedial to plantar-lateral force across the 1st metatarsal base 1
• Evaluate sagittal plane motion (>4 degrees indicates hypermobility) 1
• Assess transverse plane motion (>8 degrees indicates hypermobility) 1

Treatment Algorithm

1. Stable Injuries

• Non-weightbearing in a below-knee cast or splint for 6 weeks 1, 4
• Followed by partial progressive weightbearing with arch support from weeks 6-12 1
• Full weightbearing and return to activity at 12-16 weeks 1

2. Unstable Injuries

• Surgical intervention required 1, 5, 6

Surgical Options:

1. Open Reduction and Internal Fixation (ORIF):

   • Dorsal bridging plates to avoid transarticular screw damage 5
   • "Homerun" screw from medial cuneiform to base of second metatarsal 5
   • Kirschner wire fixation for fourth and fifth tarsometatarsal joints 5

2. Primary Arthrodesis:

   • Particularly effective for purely ligamentous Lisfranc injuries 4
   • Better functional outcomes and increased cost-effectiveness compared to ORIF for ligamentous injuries 4

Surgical Approach:

• Modified dorsal approach using a single incision with subcutaneous windows to the medial TMTJ 7
• Alternative: Multiple longitudinal incisions or single transverse incision 7

3. Postoperative Management

• Non-weightbearing in a below-knee cast for 6 weeks 1, 5
• Removal of Kirschner wires at 6 weeks postoperatively 5
• Protected weightbearing in a walker boot for additional 6 weeks 5
• Removal of dorsal bridging plates at 4-6 months postoperatively 5
• Long-term use of appropriate footwear and orthoses 1

Special Considerations

Immobilization Options (in order of preference)

1. Non-removable knee-high total contact cast 1
2. Pre-fabricated knee-high walker 1
3. Removable knee-high device 1

Potential Complications and Pitfalls

• Delayed diagnosis: Leads to worse outcomes - maintain high index of suspicion 1
• Hardware failure and loss of reduction: Regular follow-up needed 1, 5
• Post-traumatic arthritis: Occurs in up to 45% of cases despite appropriate treatment 1
• Wound complications: Include delayed healing (3%), superficial infection (5%), and dehiscence (3%) 7
• Chronic pain and disability: Functional rehabilitation is critical to optimize outcomes 1

Key Points for Optimal Outcomes

• Early detection is crucial - suspect Lisfranc injury with midfoot swelling and plantar ecchymosis 3
• Anatomical reduction is the major determinant of good long-term outcomes 1
• Regular clinical and radiographic follow-up is essential 1
• Early detection and appropriate management of 1st TMT and intercuneiform instability prevents progression to arthritis 1