Treatment of Bimalleolar Fracture
Surgical fixation is the primary treatment for displaced bimalleolar ankle fractures, with immediate weightbearing protocols allowing faster return to function compared to traditional non-weightbearing approaches.
Surgical vs. Conservative Treatment
Operative fixation is indicated for displaced bimalleolar fractures to restore ankle joint congruence and stability 1. Surgery should be performed early, preferably within 8 hours of injury once comorbidities are controlled and soft tissue status is assessed 1.
- Conservative treatment with casting produces good results only in rare, carefully selected cases of truly non-displaced fractures that remain stable on weightbearing radiographs 1, 2
- The main risks of conservative management include secondary displacement and skin lesions inside the cast leading to infection 1
- Weightbearing stable bimalleolar fractures (oblique patterns starting at the intercollicular groove with intact posterior deltoid origin) may be treated nonoperatively with functional orthosis 2
Surgical Technique and Fixation
Anatomical locking plates represent an advance for these fractures, particularly in elderly patients with osteoporotic bone, as they allow earlier return to weightbearing 1.
- Locking plates are especially beneficial for comminuted fractures common in fragility bone 1
- Thinner plates should be preferred to minimize soft tissue complications 1
- Combined anteromedial and anterolateral approaches provide adequate exposure for bimalleolar fixation 3
- Temporary external fixation should be considered when soft tissue conditions are poor 1
Postoperative Weightbearing Protocol
Immediate weightbearing in a controlled ankle motion (CAM) boot is superior to traditional non-weightbearing protocols for return to function 4, 5.
- Immediate weightbearing results in excellent to good outcomes in 65% of patients compared to 52% with delayed weightbearing 4
- Patients with nonsedentary occupations return to work 2.25 weeks earlier with immediate weightbearing (5.7 vs 10.0 weeks) 5
- Traditional protocols requiring 6 weeks of non-weightbearing are associated with prolonged disability 5
Special Considerations for Elderly Patients
Elderly patients require adapted treatment strategies due to bone fragility, soft tissue compromise, and comorbidities 1.
- Definitive fixation is preferred if skin status allows, but external fixation remains an option for poor soft tissue conditions 1
- Transarticular fixation with retrograde or antegrade locked nailing is reasonable for patients with poor autonomy, severe osteoporosis, or catastrophic skin conditions 1
- Delayed treatment risks complete loss of autonomy and life-threatening complications from immobilization 1
- All patients aged 50 years and over should be systematically evaluated for osteoporosis and subsequent fracture risk 6
Critical Pitfalls to Avoid
- Do not delay surgery beyond 8 hours when soft tissue conditions permit, as this increases complication risk and threatens patient autonomy 1
- Avoid prolonged non-weightbearing beyond what is mechanically necessary, as this delays functional recovery without improving outcomes 4, 5
- Do not underestimate soft tissue status - skin and soft tissue damage determine treatment approach and errors are not tolerated in fragile patients 1
- Ensure rigid immobilization if conservative treatment is chosen, as inadequate immobilization leads to loss of reduction 1