Treatment of Avulsion Fracture of the Lateral Malleolus
Functional treatment with early mobilization and appropriate support is the recommended approach for avulsion fractures of the lateral malleolus, as it leads to faster recovery and return to activities compared to immobilization. 1
Diagnostic Approach
- Initial assessment should include standard radiographs with anteroposterior, mortise, and lateral projections of the ankle 2
- CT scan may be indicated for complex fracture patterns requiring preoperative planning 2
- Careful evaluation is necessary as avulsion fractures are often undetected on early radiographs 3
Treatment Algorithm
1. Non-Surgical Management (First-Line)
For most avulsion fractures of the lateral malleolus:
Initial Phase (0-2 weeks):
Intermediate Phase (2-4 weeks):
- Progressive weight-bearing based on fracture healing
- Transition from immobilization to removable boot walker 2
- Begin early mobilization exercises
Rehabilitation Phase (4+ weeks):
- Physical therapy for range of motion exercises
- Strengthening exercises once fracture healing is evident
- Balance training to prevent recurrence 2
2. Surgical Management
Consider surgical intervention for:
- Significantly displaced fragments
- Fractures with associated instability
- Cases with circulatory compromise
- Open fractures or significant soft tissue injury 2
Surgical options include:
- Open reduction and internal fixation (ORIF) with plating for optimal anatomic reduction 2
- Intramedullary fixation as an alternative in select cases 4
Expected Outcomes and Follow-up
- Regular radiographic assessment to monitor healing
- Clinical evaluation for swelling, pain, and function
- Progressive weight-bearing protocol based on fracture healing 2
- Return to sports activities typically within 13-19 weeks depending on rehabilitation protocol 2
Important Considerations
- Avulsion fractures of the lateral ankle ligaments are more common than previously believed, representing approximately 26% of severe inversion injuries 3
- These injuries require a high level of suspicion for accurate diagnosis, particularly in children 3
- Functional treatment leads to faster resumption of work and daily activities compared to immobilization 1
- Monitor for complications such as chronic pain (affects ~20% of patients), osteonecrosis, post-traumatic arthritis, malunion, nonunion, and infection 2
Prevention of Recurrence
- Neuromuscular training has shown significant preventive effect for recurrent ankle sprains 1
- Functional support (bracing) is effective in preventing both first-time and recurrent lateral ankle sprains 1
- Both preventive approaches have shown high cost benefits 1
Remember that early mobilization with appropriate support provides better outcomes than prolonged immobilization, with faster return to work, sports, and daily activities 1.