What is the treatment for displaced fractures of the medial, posterior, and lateral malleolus of the right ankle?

Treatment of Displaced Trimalleolar Ankle Fracture

Displaced fractures involving all three malleoli (medial, lateral, and posterior) require surgical intervention with open reduction and internal fixation (ORIF) to restore ankle stability and prevent post-traumatic arthritis. 1

Initial Assessment and Imaging

• Obtain standard three-view ankle radiographs (anteroposterior, lateral, and mortise views) to evaluate fracture displacement, joint alignment, and the extent of posterior malleolar involvement 1, 2
• Weight-bearing radiographs are critical if the patient can tolerate them, as they provide essential information about fracture stability—the most important criterion determining treatment approach 1, 2
• A medial clear space >4 mm indicates instability and confirms the need for surgical intervention 1, 2
• CT scanning should be obtained to determine the exact size and displacement of the posterior malleolar fragment, particularly when it involves >25-30% of the articular surface 3, 4

Surgical Treatment Algorithm

Lateral Malleolus Fixation (First Priority)

• Anatomic reduction of the lateral malleolus is mandatory as it serves as the key to restoring fibular length and ankle mortise alignment 5
• Standard plate and screw fixation remains the gold standard for lateral malleolar fractures, providing stable fixation and allowing early mobilization 6
• Alternative: Intramedullary fibular nailing may be considered in patients with compromised soft tissues or significant comorbidities, though it has a higher rate of secondary procedures (>20% requiring hardware removal) 6

Posterior Malleolus Fixation (Second Priority)

• Direct fixation is indicated when the fragment is >25-30% of the articular surface or when significant displacement persists after lateral malleolar reduction 3, 4
• Posterolateral approach with posterior plating is preferred over traditional anteroposterior screw fixation, as it allows direct visualization, anatomic reduction, and more stable fixation 3, 4
• Adequate reduction is defined as <2 mm articular surface displacement on final radiographs 3

Medial Malleolus Fixation (Final Step)

• Fix the medial malleolus after lateral and posterior malleolar stabilization, as it often reduces anatomically once the fibula is restored to proper length 2, 7
• Standard fixation techniques include screws or tension band wiring depending on fracture pattern and bone quality 2
• In rare cases with severe soft tissue compromise, the medial malleolus may be left unfixed if anatomic reduction is achieved and maintained, though this is not standard practice 7

Postoperative Management

• Below-knee cast immobilization for 6-8 weeks is necessary for adequate healing, regardless of internal fixation method 5
• Serial radiographs are essential to confirm maintenance of reduction and assess healing progression 2, 3
• Early mobilization and physical therapy should begin once adequate healing is confirmed to prevent stiffness and optimize functional outcomes 1

Critical Pitfalls to Avoid

• Failure to achieve anatomic reduction of the lateral malleolus compromises the entire reconstruction, as fibular length determines mortise alignment 5
• Underestimating posterior malleolar involvement leads to persistent posterior instability and poor outcomes—always assess fragment size carefully 3, 4
• Inadequate soft tissue assessment can result in wound complications, particularly with medial approaches in high-energy injuries 7
• Premature weight-bearing before adequate healing risks hardware failure, loss of reduction, and nonunion 2