What is the recommended management of a distal femur fracture in an adult?

Management of Distal Femur Fractures in Adults

Surgical Treatment is Mandatory

Surgical stabilization is the standard treatment for distal femur fractures in adults, with device selection based on fracture pattern: use a distal femur locking compression plate (DFLCP) for intra-articular and highly comminuted fractures, or a retrograde intramedullary supracondylar nail (IMSCN) for extra-articular fractures. 1, 2, 3

Device Selection Algorithm

For Intra-Articular Fractures (AO/OTA Type 33C)

• DFLCP is the preferred implant for inter-condylar (intra-articular) and highly comminuted distal femur fractures, as it provides anatomic reduction and stable fixation 1
• Open reduction with internal fixation using lag screws for articular fragments, followed by plate application 2, 3

For Extra-Articular Fractures (AO/OTA Type 33A)

• Retrograde IMSCN is appropriate for extra-articular metaphyseal-diaphyseal fractures 1, 3
• Results in less soft tissue compromise, preserves fracture hematoma, and achieves earlier union (average 7.15 months vs 8.15 months for DFLCP) 1
• Average blood loss is significantly lower (242.85 ml vs 425 ml for DFLCP) 1

Distal Femur Replacement (DFR)

• Avoid DFR in favor of ORIF, as DFR is associated with significantly higher risk of transfusion, infection, revision surgery, and mechanical complications at 1 and 5 years postoperatively 4

Surgical Timing

Perform surgery within 24 to 48 hours of hospital admission to minimize morbidity (pressure sores, pneumonia, thromboembolic complications) and mortality 5, 6

Perioperative Management

Anesthesia

• Either spinal or general anesthesia is appropriate, with no superiority of one over the other 7, 8, 6
• Spinal anesthesia may reduce postoperative confusion in elderly patients 7, 8

Pain Management

• Administer multimodal analgesia with preoperative femoral nerve block 7, 8, 6
• Continue regular paracetamol throughout the perioperative period 7, 6
• Use opioids cautiously, especially in patients with renal dysfunction; avoid codeine due to constipation and cognitive dysfunction risk 7, 6

Infection Prophylaxis

• Administer prophylactic antibiotics within one hour of skin incision 7, 8, 6

Thromboprophylaxis

• Administer fondaparinux or low molecular weight heparin for DVT prophylaxis 7, 6
• Continue pharmacologic prophylaxis for 4 weeks postoperatively 6

Temperature Management

• Implement active warming strategies intraoperatively and continue postoperatively to prevent hypothermia 7, 6

Postoperative Rehabilitation

Allow early weight bearing as tolerated immediately after surgery without specific restrictions 9

• Early weight bearing enhances bone healing and does not increase risk of fracture displacement or implant failure 9
• Non-weight-bearing status may delay fracture healing and increase risk of fixation failure 9
• Begin physical therapy on postoperative day one if medically stable 7

Critical Technical Considerations

For DFLCP Fixation

• Achieve anatomic reduction under fluoroscopic guidance in both AP and lateral views 6
• Ensure restoration of medial cortical continuity and normal neck-shaft angle (approximately 130-135 degrees) 6
• Position plate flush against lateral femoral cortex with bicortical screw purchase 6

Common Pitfalls to Avoid

• Inadequate reduction before fixation leads to malunion and hardware failure 6
• Over-compression causes fracture comminution in osteoporotic bone 6
• Soft tissue compromise in open grade 3B fractures negatively affects functional outcomes 1

Expected Outcomes

• Functional outcomes are comparable between DFLCP and IMSCN, with 46% and 42.85% excellent results respectively by Schatzker and Lambert criteria 1
• Average union time: 7.15 months for IMSCN, 8.15 months for DFLCP 1

Long-Term Follow-Up

• Arrange outpatient DEXA scan and referral to bone health clinic for osteoporosis evaluation and treatment 7, 6
• Monitor for complications including infection, hardware failure, and nonunion 3, 4