What is the step-by-step procedure for treating a posterior malleolus fracture with plating?

Posterior Malleolus Fracture Plating: Step-by-Step Procedure

The optimal surgical approach for posterior malleolus fracture fixation is direct visualization through a posterolateral approach with anatomical reduction and plate fixation, which provides superior stability and functional outcomes compared to percutaneous anterior-to-posterior screw fixation. 1, 2

Preoperative Assessment and Planning

1. CT Scan Evaluation

   • Obtain high-quality CT scan to classify fracture pattern using Haraguchi or Bartoníček classification 2
   • Determine fragment size, displacement, and involvement of articular surface
   • Plan surgical approach based on fracture pattern:
     • Posterolateral approach: For Haraguchi I/III or Bartoníček 1/2/4 fractures
     • Posteromedial approach: For Haraguchi II or Bartoníček 3 fractures 2

2. Patient Positioning

   • Position patient prone for posterolateral approach or supine for modified posteromedial approach
   • Place a bolster under the affected ankle for better exposure

Surgical Procedure: Posterolateral Approach

Step 1: Incision and Exposure

1. Make a 10-12 cm longitudinal incision between the lateral border of the Achilles tendon and the fibula
2. Identify and protect the sural nerve
3. Develop the interval between the peroneal tendons and flexor hallucis longus (FHL) 2, 3
4. Retract the peroneal tendons laterally and the FHL medially

Step 2: Fracture Visualization and Preparation

1. Identify the posterior malleolus fragment
2. Clear the fracture site of hematoma and debris
3. Assess the fracture pattern and articular surface involvement
4. Identify the syndesmotic attachments, particularly the posterior inferior tibiofibular ligament (PITFL)

Step 3: Fracture Reduction

1. Apply longitudinal traction to the foot to disengage the fracture fragments
2. Use a periosteal elevator or small bone hook to manipulate the fragment
3. Reduce the fragment anatomically, ensuring perfect alignment of the articular surface
4. Confirm reduction visually and with fluoroscopy
5. Apply temporary K-wire fixation to maintain reduction

Step 4: Plate Application and Fixation

1. Select appropriate plate (typically a posterior buttress or one-third tubular plate)
2. Contour the plate to match the posterior malleolar surface
3. Position the plate to provide buttress support to the reduced fragment
4. Insert at least 3-4 screws through the plate into the fragment and proximal tibia
5. For associated fibular fractures, either:
   • Fix through the same incision with a posterolateral plate, or
   • Create a subcutaneous window for lateral approach fixation 2

Step 5: Intraoperative Assessment

1. Verify anatomic reduction using fluoroscopy in multiple planes
2. Check ankle stability through range of motion
3. Assess syndesmotic stability with stress tests
4. Apply additional syndesmotic fixation if needed

Step 6: Wound Closure

1. Irrigate the wound thoroughly
2. Close the deep fascia with absorbable sutures
3. Close subcutaneous tissue and skin in layers
4. Apply sterile dressing and splint

Postoperative Management

1. Immediate Postoperative Care

   • Elevate the extremity to reduce swelling
   • Apply ice following the PRICE protocol (protection, rest, ice, compression, elevation) 4
   • Monitor neurovascular status

2. Rehabilitation Protocol

   • Non-weight bearing for 4-6 weeks with cast or boot immobilization
   • Progressive weight bearing starting at 6 weeks based on radiographic healing
   • Range of motion exercises starting at 2 weeks if fixation is stable
   • Full weight bearing typically by 8-12 weeks 4

Special Considerations

1. Fragment Size and Fixation Method

   • While fragment size alone is not the sole determinant for fixation method, it influences technique selection 1, 5
   • For fragments >25% of the articular surface, plate fixation provides superior stability compared to screws 5
   • For smaller fragments (<25%), two 4.0mm lag screws may provide adequate fixation 5

2. Anatomical Reduction Priority

   • Non-anatomical reduction has greater negative impact on outcomes than fragment size 1
   • Step-off >2mm significantly increases risk of post-traumatic osteoarthritis 1

3. Associated Injuries

   • Address associated fibular and medial malleolar fractures during the same procedure
   • Assess and repair syndesmotic injuries as needed

Potential Complications

1. Monitor for:
   • Wound healing problems
   • Infection
   • Malunion or nonunion
   • Post-traumatic arthritis
   • Chronic pain (affects approximately 20% of patients) 4

The posterolateral approach with direct visualization and plate fixation has demonstrated superior outcomes compared to traditional percutaneous techniques, providing better stability and allowing for more accurate reduction of the articular surface 1, 3.