What is a Maisonneuve fracture?

Maisonneuve Fracture

A Maisonneuve fracture is a complex ankle injury characterized by a proximal fibular fracture (typically in the proximal third), complete rupture of the anterior inferior tibiofibular ligament, disruption of the syndesmosis, and medial ankle injury (either deltoid ligament rupture or medial malleolus fracture). 1, 2

Pathoanatomy and Characteristics

• Maisonneuve fractures account for approximately 7% of all ankle fractures 3
• The fracture typically involves the proximal third of the fibula, with most cases (85.37%) showing a fracture in the proximal fibular shaft 1
• The injury pattern includes:
  • Proximal fibular fracture (100% of cases) 1
  • Complete rupture of the anterior inferior tibiofibular ligament (100% of cases) 1
  • Posterior malleolar fracture (77-83% of cases) 4, 1
  • Medial malleolus fracture (39-73% of cases) or deltoid ligament rupture (24-51% of cases) 4, 1

Injury Mechanism

• The main injury mechanism is pronation-external rotation of the ankle 1
• The fracture line in the proximal fibula typically runs from anterosuperior to posteroinferior 1
• The injury involves a sequential failure of structures:
  • Initial medial injury (either deltoid ligament tear or medial malleolus fracture)
  • Syndesmotic disruption
  • Proximal fibular fracture due to continued external rotation force 2

Diagnostic Approach

• Standard radiographic protocol should include:
  • Anteroposterior, lateral, and mortise views of the ankle 5
  • Lateral and anteroposterior views of the entire leg (as the fibular fracture may be missed on ankle radiographs alone) 4
• CT scanning is essential for accurate assessment and should be considered standard in Maisonneuve fractures 2
  • In 24% of cases, the fibular fracture is only visible on lateral radiographs of the lower leg 4
  • CT helps identify posterior malleolar fractures and malposition of the distal fibula in the fibular notch 2
• MRI can be valuable for assessing associated soft tissue injuries, particularly when evaluating syndesmotic and deltoid ligament integrity 3

Treatment Considerations

• The main goal of treatment is anatomical reduction of the distal fibula into the fibular notch 2
• Surgical management is typically recommended:
  • Open reduction and internal fixation (ORIF) of the medial ankle injury and syndesmotic disruption 3
  • The proximal fibular fracture often does not require fixation 3
  • In cases with posterior malleolar fracture, reduction and fixation from a posterolateral approach is recommended first 2
• Open reduction of the distal fibula is preferred over closed reduction, as closed reduction is associated with malposition in up to 50% of cases 2
• Post-operative CT scan is recommended to verify accurate reduction 2

Potential Complications

• Malreduction of the distal fibula in the fibular notch can lead to poor outcomes 2
• Post-traumatic arthritis may develop if anatomical reduction is not achieved 6
• Chronic ankle instability can occur with inadequate treatment 6

Special Considerations

• Conservative treatment with casting may be considered in select cases, though surgical management is generally preferred 6
• A recent case report showed favorable outcomes with conservative treatment using a short leg cast for 8 weeks in a young patient with minimal syndesmotic disruption 6
• Accuracy of reduction should always be verified with post-operative imaging 2