What are the treatment options for different types of distal femur fractures?

Distal Femur Fracture Types and Treatment Options

The optimal treatment for distal femur fractures depends on fracture type, with intramedullary supracondylar nails (IMSCN) recommended for extra-articular fractures and distal femoral locking compression plates (DFLCP) preferred for intra-articular or highly comminuted fractures. 1

Classification of Distal Femur Fractures

Distal femur fractures can be broadly classified into:

1. Extra-articular fractures (supracondylar)
2. Intra-articular fractures (intercondylar)
3. Periprosthetic fractures (around knee implants)

Treatment Options Based on Fracture Type

Extra-articular Fractures

• Intramedullary Supracondylar Nails (IMSCN)
  • Advantages: Less blood loss (average 242.85ml vs 425ml with plates), shorter union time (7.15 months vs 8.15 months), preservation of fracture hematoma 1
  • Best for: Stable fractures without articular involvement
  • Technique: Closed reduction to maintain soft tissue envelope

Intra-articular Fractures

• Distal Femoral Locking Compression Plate (DFLCP)
  • Advantages: Better anatomic reduction of articular surface, stable fixation for comminuted fractures 1
  • Best for: Intercondylar fractures requiring anatomical joint reconstruction
  • Results: 76% excellent to good outcomes in intra-articular fractures 2
  • Technique: Open reduction and internal fixation (ORIF) with anatomical reduction of articular fragments

Periprosthetic Fractures

• Treatment options include:

  1. ORIF with periarticular locking plates

     • Higher functional scores compared to distal femoral replacement 3
     • Higher risk of nonunion and revision surgery

  2. Intramedullary nailing

     • Higher malunion rates compared to plating 4
     • Similar major complication rates to other methods

  3. Distal femoral replacement (DFR)

     • Higher deep infection rates compared to internal fixation 4
     • Recommended for severely comminuted fractures with poor bone quality or failed internal fixation

Special Considerations

Open Fractures

• Significantly higher complication rates (52.4%) 5
• Common complications include:
  • Nonunion (38%)
  • Deep infection (28.5%)
  • Average time to union: 20.4 months 5
• Treatment approach:
  • Initial external fixation may be required
  • Definitive fixation with either IMSCN (28.6%) or locked plating (71.4%) 5

Elderly Patients

• Balanced approach between operative and non-operative treatment is crucial 6
• Consider bone quality when selecting fixation devices and techniques
• Orthogeriatric co-management improves functional outcomes and reduces mortality

Rehabilitation Protocol

• Early mobilization after stable surgical fixation is beneficial for optimal outcomes
• Directed home exercise program including active motion exercises helps prevent stiffness
• Limiting immobilization duration reduces complications

Potential Complications

• Joint stiffness (reported in 12% of cases) 2
• Infection (8% in early post-operative period) 2
• Nonunion or delayed union
• Hardware failure
• Post-traumatic arthritis

Treatment Algorithm

1. Assess fracture pattern:

   • Extra-articular → Consider IMSCN
   • Intra-articular → DFLCP preferred
   • Periprosthetic → Base decision on bone quality, comminution, and prosthesis stability

2. Evaluate bone quality:

   • Good bone stock → Internal fixation (ORIF or IMSCN)
   • Poor bone quality/severe comminution → Consider DFR

3. Consider open vs. closed fractures:

   • Closed fractures → Standard protocol based on fracture pattern
   • Open fractures → Aggressive debridement, possible temporary external fixation, followed by definitive fixation when soft tissues permit

The evidence shows comparable functional outcomes between DFLCP and IMSCN, with specific advantages for each technique depending on fracture pattern 1. The primary goal remains anatomical reduction of articular fragments and rigid fixation to allow early mobilization.