What is the initial treatment for an acute transverse nondisplaced fracture of the lateral malleolus with associated soft tissue swelling?

Initial Treatment for Acute Transverse Nondisplaced Fracture of the Lateral Malleolus

Functional treatment with a removable ankle brace or short-leg walking cast is the recommended initial treatment for an acute transverse nondisplaced fracture of the lateral malleolus with associated soft tissue swelling. 1

Diagnostic Evaluation

• Initial assessment should include standard three-view ankle radiographs (anteroposterior, lateral, and mortise views) to evaluate the fracture and overall ankle alignment 1
• Weight-bearing radiographs, if possible, provide important information about fracture stability, as the most important criterion in treatment is stability 1
• A medial clear space of <4 mm confirms stability of the ankle mortise 1

Treatment Algorithm

Step 1: Assess Fracture Stability

• Evaluate for signs of instability such as:
  • Medial tenderness, bruising, or swelling
  • Fibular fracture above the syndesmosis
  • Open fracture or high-energy injury 1
• Consider gravity stress views which are more reliable than manual stress views for evaluating ankle stability 1

Step 2: Treatment for Stable Nondisplaced Lateral Malleolus Fracture

• For stable fractures (confirmed by intact mortise and <4mm medial clear space):
  • Functional treatment with a removable ankle brace or short-leg walking cast for 4-6 weeks 1, 2
  • Early weight-bearing as tolerated is recommended to facilitate faster return to work and daily activities 1
  • Ice, compression, and elevation for the first 3-5 days to manage soft tissue swelling 1

Step 3: Follow-up and Rehabilitation

• Regular radiographic follow-up at 2-3 weeks to confirm maintained alignment 3
• Progressive weight-bearing and active range of motion exercises after initial period of protection 1
• Consider physical therapy for strengthening and proprioception training to prevent recurrent ankle sprains 1

Special Considerations

• In patients with demineralized bone (as noted in the radiographic report), careful monitoring is needed as fractures may be radiographically occult 1
• MRI may be considered if there is persistent pain despite appropriate treatment, to evaluate for bone marrow edema or occult fractures 1
• For patients with high functional demands, a semirigid brace may be the most cost-effective option compared to taping 1

Potential Complications and How to Avoid Them

• Nonunion is rare but can occur in lateral malleolus fractures 4
• Risk factors for complications include inadequate immobilization or premature weight-bearing 4
• Persistent pain and swelling may indicate need for further imaging to rule out occult injuries 1
• Reflex sympathetic dystrophy can develop as a complication in some cases 4

When to Consider Surgical Management

• Surgery is generally reserved for:
  • Unstable fractures with widening of the ankle mortise
  • Displaced fractures that cannot be reduced by closed means
  • Fractures with loss of position during conservative treatment 2
• If surgical intervention becomes necessary, both traditional plate fixation and intramedullary fixation techniques have shown good outcomes 5