What is the treatment for a trimalleolar fracture?

Treatment of Trimalleolar Fractures

Trimalleolar fractures require surgical treatment with open reduction and internal fixation (ORIF) to restore anatomic alignment and ankle stability, as these are inherently unstable injuries that lead to poor functional outcomes and post-traumatic arthritis if managed non-operatively.

Initial Diagnostic Approach

Imaging Protocol

• Standard three-view ankle radiographs (anteroposterior, lateral, and mortise views) are the initial imaging study of choice for acute ankle trauma meeting Ottawa Ankle Rules criteria 1
• Weight-bearing radiographs should be obtained when possible to assess fracture stability, as medial clear space <4 mm confirms stability 1
• CT imaging is indicated for complex trimalleolar fractures to determine the extent of injury, particularly for posterior malleolus fragment characterization and surgical planning 1
• Increased instability is noted with medial tenderness/swelling, fibular fracture above the syndesmosis, or trimalleolar fracture patterns 1

Surgical Treatment Algorithm

Operative Indications

All trimalleolar fractures are inherently unstable and require surgical fixation to restore the ankle mortise and prevent talar subluxation 2, 3. The key principle is anatomic reduction of all three malleolar fragments with stable internal fixation.

Surgical Technique Considerations

Fragment-Specific Fixation Approach

• Low-profile anatomical fragment-specific implants achieve excellent functional outcomes with mean MOXFQ scores of 34.3 and FADI scores of 77.9, with radiological union at mean 7.4 weeks 4
• This modern approach allows tailored fixation based on individual fracture patterns 4

Posterior Malleolus Management

• Direct fixation of the posterior malleolus is increasingly favored, with prone positioning allowing optimal visualization and reduction 3
• Fixation of posterior fragments provides bone-to-bone syndesmotic stability and restores the physiological tibial incisura shape 3
• After anatomic fixation of all malleolar fragments, only 4% of patients require additional syndesmotic screw fixation 3

Alternative Surgical Approaches

• Arthroscopically assisted reduction and minimally invasive surgery (AARMIS) achieves comparable radiographic and functional outcomes to traditional ORIF, with similar rates of early ankle osteoarthritis and no significant differences in pain scores or range of motion at mean 36-month follow-up 5
• AARMIS may be considered as an alternative to standard ORIF in appropriate cases 5

Prognostic Factors to Consider

Negative prognostic indicators that predict worse surgical outcomes include 2:

• Age >61 years
• BMI >40
• ASA score >1
• Danis-Weber type C fractures
• Fracture-dislocation patterns

These factors should inform preoperative counseling and may necessitate more aggressive rehabilitation protocols 2.

Postoperative Management

Immediate Postoperative Care

Key elements include 1:

• Appropriate pain management
• Antibiotic prophylaxis
• Correction of postoperative anemia
• Assessment for pressure sores and wound complications
• Early mobilization when fracture stability permits

Rehabilitation Protocol

• Early introduction of physical training and muscle strengthening combined with long-term balance training and multidimensional fall prevention programs 1
• This approach optimizes functional recovery and reduces subsequent fracture risk

Critical Pitfalls to Avoid

• Avoid manipulation prior to radiographs unless neurovascular deficit or critical skin injury is present, as this may complicate subsequent management 1
• Do not underestimate posterior malleolus fragments: even small fragments can cause talar subluxation and lead to post-traumatic arthritis if not addressed 6, 3
• Inadequate syndesmotic assessment: after fixation of all malleolar fragments, intraoperative testing for residual syndesmotic instability is essential 3
• Failure to address quadrimalleolar patterns: when anterior tibial tubercle or anterior fibular rim fractures are present, these require fixation to restore complete ankle stability 3

Secondary Fracture Prevention

For patients ≥50 years with trimalleolar fractures 1:

• Systematic evaluation for subsequent fracture risk through Fracture Liaison Service coordination
• Assessment of bone density, falls risk, and secondary osteoporosis causes
• Pharmacological treatment with agents proven to reduce vertebral, non-vertebral, and hip fracture risk
• Adequate calcium and vitamin D supplementation, smoking cessation, and alcohol limitation