What is the step-by-step procedure for treating pelvis diastasis using Open Reduction Internal Fixation (ORIF) with plating?

Step-by-Step Procedure for Pelvis Diastasis Plating

Pubic symphysis plating represents the modality of choice for anterior fixation of "open book" injuries with a pubic symphysis diastasis > 2.5 cm (APC-II, APC-III) injuries. 1

Pre-Operative Assessment and Planning

• Classification of Injury: Determine the type of pelvic injury using the Young & Burgess classification system:

  • APC-I: Stable, can be managed non-operatively
  • APC-II/APC-III: Rotationally unstable "open book" injuries requiring definitive internal fixation
  • LC-II/LC-III: Rotationally and vertically unstable patterns requiring fixation 1

• Imaging: Complete CT scan to evaluate:

  • Extent of symphyseal diastasis
  • Associated posterior pelvic ring injuries
  • Presence of other pelvic fractures 1

• Timing of Surgery:

  • Hemodynamically stable patients: Safe to proceed within 24 hours post-injury
  • Hemodynamically unstable patients: Stabilize first with temporary external fixation if needed
  • Physiologically deranged polytrauma patients: Postpone definitive fixation until after day 4 post-injury 1

Surgical Procedure

1. Patient Positioning and Preparation

• Position patient supine on a radiolucent table
• Prepare and drape the entire lower abdomen, pubic area, and proximal thighs
• Ensure C-arm availability for intraoperative fluoroscopic guidance

2. Surgical Approach

• Pfannenstiel Approach (standard):

  • Make a transverse curvilinear incision 2 cm above the pubic symphysis, extending laterally
  • Incise the anterior rectus sheath and separate the rectus abdominis muscles in the midline
  • Carefully protect the bladder by retracting it posteriorly 2, 3

• Alternative: Midline approach may be used in select cases where Pfannenstiel approach is not ideal 3

3. Reduction Technique

• Expose the pubic symphysis and debride any hematoma or interposed soft tissue
• Use a pointed reduction clamp to grasp the pubic bodies on each side
• Apply compression to reduce the diastasis
• Verify anatomic reduction using fluoroscopy in AP, inlet, and outlet views 2

4. Fixation Options

• Standard Technique: Single anterior plate fixation

  • Apply a 4-6 hole reconstruction plate or symphyseal plate across the pubic symphysis
  • Place at least 2 screws on each side of the symphysis
  • Ensure screws are directed superiorly and posteriorly to avoid bladder injury 2, 3

• Alternative Technique: Double plate fixation

  • Apply a second plate perpendicularly to the first plate (one superior and one anterior)
  • This provides increased stability for more unstable injuries 2, 4

• Screw Placement:

  • Use 3.5 mm cortical screws
  • Ensure adequate screw length to engage the posterior cortex
  • Avoid excessive penetration to prevent vascular injury 2

5. Assessment of Stability

• After plate application, test stability by manual manipulation
• Obtain intraoperative fluoroscopic images in AP, inlet, and outlet views to confirm:
  • Adequate reduction of the symphysis
  • Proper plate and screw positioning
  • Overall pelvic alignment 1

6. Additional Posterior Fixation (if needed)

• For APC-III injuries with posterior instability:
  • Perform posterior fixation using iliosacral screws or posterior plating
  • This can be done in the same setting or as a staged procedure depending on patient condition 1, 2

7. Wound Closure

• Irrigate the wound thoroughly
• Close the rectus sheath with strong absorbable sutures
• Ensure meticulous closure of the rectus sheath to prevent postoperative complications such as bladder herniation 2
• Close subcutaneous tissue and skin in layers

Post-Operative Management

• Mobilization:

  • For isolated anterior ring injuries (APC-II): Early mobilization possible, often within 1 day 5
  • For combined anterior-posterior injuries (APC-III): Delayed weight-bearing may be necessary

• Weight-bearing Protocol:

  • Initial toe-touch weight bearing for 6-8 weeks
  • Progressive weight bearing as tolerated after radiographic evidence of healing

• Follow-up:

  • Regular radiographic assessment at 2,6, and 12 weeks post-surgery
  • Evaluate for implant failure, loss of reduction, or other complications

Potential Complications

• Implant Failure: Occurs in some cases but studies show this may not significantly impact clinical outcomes 3
• Infection: Risk of surgical site infection (2-5%)
• Deep Venous Thrombosis: Requires appropriate prophylaxis
• Bladder Herniation: Can occur with inadequate repair of rectus sheath 2
• Malreduction: May lead to chronic pain and functional limitations

Special Considerations

• Limited Dissection: Ensure adequate intactness of rectus sheath to avoid long-term post-operative complications 2
• Hemodynamic Status: In patients with severe hemodynamic instability, consider temporary external fixation before definitive internal fixation 1
• Open Pelvic Fractures: These rare injuries (1.7% of pelvic fractures) require specialized management with focus on bleeding control and prevention of contamination 1