What is the step-by-step procedure for treating a comminuted fracture of the distal femur using medial distal femur plates?

Surgical Management of Comminuted Distal Femur Fractures Using Medial Distal Femur Plates

The optimal surgical approach for comminuted distal femur fractures involves anatomical distal femur locking compression plates (DFLCP) applied medially, which provides superior stability for intra-articular and highly comminuted fractures while ensuring proper alignment and early mobilization to reduce morbidity and mortality.

Pre-operative Assessment and Planning

Imaging

• Begin with standard radiographs (AP and lateral views) of the distal femur
• Obtain CT scan for detailed fracture pattern assessment, especially for intra-articular involvement
  • CT has 69-87% sensitivity for detecting occult fractures 1
• Consider MRI if radiographs are negative but clinical suspicion remains high (nearly 100% sensitivity) 1

Patient Evaluation

• Assess bone quality (osteoporosis increases complication risk)
• Evaluate soft tissue condition around the fracture site
• Check for associated injuries (ipsilateral hip fracture, knee ligament injuries)
• Review medical comorbidities that may affect surgical outcomes

Surgical Technique for Medial Distal Femur Plating

Step 1: Patient Positioning and Preparation

• Position patient supine on a radiolucent table
• Place a bump under the ipsilateral hip to internally rotate the leg slightly
• Prepare and drape the entire limb to allow intraoperative manipulation

Step 2: Surgical Approach

• Make a medial parapatellar incision extending proximally along the medial aspect of the thigh
• Develop the interval between vastus medialis and adductor magnus
• Protect the femoral vessels and saphenous nerve during exposure

Step 3: Fracture Reduction

• Perform anatomic reduction of the articular surface first (crucial for intra-articular fractures)
• Use K-wires for provisional fixation of articular fragments
• Restore length, alignment, and rotation of the femoral shaft relative to the condyles
• Consider using a femoral distractor to aid in reduction

Step 4: Plate Application

• Select an appropriately sized anatomical distal femur locking compression plate
• Position the plate on the medial aspect of the distal femur
• Secure the plate to the distal fragment with locking screws
• Ensure proper alignment before securing the plate to the shaft
• Use a combination of locking and non-locking screws as appropriate

Step 5: Additional Fixation (if needed)

• For highly comminuted fractures, consider double-plating technique with an additional lateral plate 2
• Apply bone graft to address bone defects and promote healing
• In cases with significant bone loss, consider structural allograft

Step 6: Wound Closure

• Irrigate thoroughly
• Close the wound in layers
• Apply sterile dressing

Postoperative Management

Immediate Care

• Administer thromboembolism prophylaxis (sequential compression devices during hospitalization followed by pharmacological prophylaxis for 4 weeks) 1
• Monitor hemoglobin levels closely, especially with comminuted fractures which can have significant blood loss 1
• Administer tranexamic acid to reduce blood loss and need for transfusion 1
• Provide multimodal pain management, limiting opioid use especially in geriatric patients 1

Mobilization Protocol

• Begin early mobilization to improve respiratory function 1
• Implement immediate, full weight-bearing to tolerance after surgery for most comminuted fractures 1
• Initiate physical therapy for range of motion exercises within 24-48 hours post-surgery

Follow-up Schedule

• Obtain radiographs at 2,6, and 12 weeks post-surgery 1
• Monitor for signs of implant failure, loss of reduction, or delayed union
• Average union time for DFLCP is approximately 8.15 months 3

Outcomes and Complications

Expected Outcomes

• DFLCP provides anatomic and stable fixation for comminuted and intra-articular distal femur fractures 3
• Excellent results can be expected in approximately 46% of cases treated with DFLCP 3

Potential Complications

• Higher intraoperative blood loss compared to intramedullary nailing (average 425 ml vs. 242.85 ml) 3
• Risk of infection, particularly with open fractures
• Hardware prominence or irritation requiring removal
• Nonunion or delayed union (less common with proper technique)
• Knee stiffness (may require quadricepsplasty in some cases) 4

Special Considerations

Severely Comminuted Open Fractures

• For grade IIIB open fractures with extensive soft tissue injury, consider limited internal fixation combined with external fixation 4
• External fixation may be used as a temporizing measure before definitive internal fixation

Elderly Patients with Poor Bone Quality

• In elderly patients with severely comminuted fractures and poor bone quality, distal femoral replacement (DFR) may be considered as an alternative to ORIF 5
• DFR shows trends toward lower revision and reoperation rates compared to ORIF in these patients 5

Atypical Femoral Fractures

• Be vigilant for atypical femoral fractures in patients on long-term bisphosphonate therapy 6
• These fractures have characteristic features: minimal trauma, transverse orientation, noncomminuted pattern, and lateral cortical thickening 6

By following this systematic approach to the surgical management of comminuted distal femur fractures using medial distal femur plates, optimal outcomes can be achieved with appropriate patient selection and meticulous surgical technique.