How should a depressed fracture of the lateral tibial plateau be managed?

Management of Depressed Lateral Tibial Plateau Fractures

For depressed lateral tibial plateau fractures, obtain CT imaging immediately after radiographic diagnosis to characterize fracture severity and guide surgical planning, followed by open reduction and internal fixation (ORIF) with direct visualization of the articular surface, anatomic reduction, bone grafting of metaphyseal defects, and stable fixation with locking plates and subchondral screws 1.

Initial Imaging Algorithm

After clinical diagnosis with radiographs showing tibial plateau fracture:

• CT without contrast is mandatory for fracture classification and surgical planning 1

  • CT demonstrates 100% sensitivity versus 83% for radiographs alone 1
  • Quantifies degree of articular depression
  • Identifies fragment morphology and posterior column involvement
  • Depression >11 mm predicts higher risk of lateral meniscus tear and ACL avulsion 1

• MRI without contrast is equally appropriate as an alternative or adjunct 1

  • Superior for detecting associated meniscal and ligamentous injuries
  • Identifies bone marrow contusions and occult fractures
  • Consider when CT shows significant depression suggesting soft tissue injury

Surgical Approach Selection

The surgical approach depends on fracture location and depression characteristics:

Standard Anterolateral Approach with Lateral Submeniscal Arthrotomy 2

Use for most lateral plateau depressions with accessible articular surface:

• Supine positioning
• Anterolateral incision with lateral submeniscal arthrotomy
• Direct visualization of articular surface is essential - do not rely on indirect reduction
• Temporary fixation with K-wires during reduction

Lateral Tibial Plateau Osteotomy 3, 4

Consider for central-lateral depressions (CLD) with intact lateral cortical rim:

• Provides direct access when standard approaches limit visualization 3
• Particularly useful for deep, angulated, or reverse-slope depressions 3
• Allows easy meniscal retrieval and anatomical reduction 3
• All reported cases achieved union with good functional outcomes 3

Lateral Femoral Epicondyle Osteotomy 5

Use specifically for posterolateral corner depressions:

• Mean reduction achieved: 15.8 mm with anatomical reduction in 62% of patients 5
• Excellent functional scores (mean Knee Society Score 92, Lysholm 92) 5
• No fibular nerve complications reported 5

Arthroscopic-Assisted Technique 6, 7

Limited role - primarily for monitoring rather than primary reduction:

• Current arthroscopic portals provide only tangential viewing of peripheral areas 7
• Meniscotibial attachments remain intact, severely constraining instrument maneuverability 7
• May be useful in select cases with precision drill guides and allograft 6
• Not recommended as primary approach for significant depressions

Reduction and Fixation Technique

Key Technical Steps 2, 8:

1. Cut lateral cortex to expose depression - do not attempt blind elevation
2. Elevate compacted cancellous bone under direct vision
3. Temporary K-wire fixation of reduced articular surface
4. Subchondral screw placement:
   • Use 2.7 mm locking screws placed subchondral for stable articular fixation 2
   • Provides superior stability compared to metaphyseal screws alone
5. Bone grafting:
   • Fill metaphyseal defects with autologous iliac crest or allograft
   • Fresh-frozen femoral head allograft is effective alternative 6
6. Plate fixation:
   • 3.5 mm variable angle locking compression plate for lateral column 2
   • One-third tubular horizontal belt plate for posterolateral fragments 5

Critical Pitfalls to Avoid

• Never rely on indirect reduction techniques - articular step-off averaging 1.0-1.2 mm persists even with good technique 8
• Inadequate visualization leads to malreduction - if you cannot see the articular surface directly, change your approach 3
• Failure to address soft tissue injuries - depression >11 mm mandates evaluation for meniscal/ligamentous injury 1
• Insufficient subchondral support - metaphyseal screws alone allow collapse; use dedicated subchondral fixation 2

Postoperative Protocol 2

• Free range of motion immediately
• Varus-valgus stabilizing brace if residual collateral ligament instability
• Partial weight-bearing 10-15 kg for 8 weeks
• CT scan at 3 months to confirm maintained reduction
• Expected outcomes: 73-85% excellent results with anatomic reduction 2, 8

Expected Complications

Based on reported series 2, 5:

• Flexion deficit ≥30°: ~15% of patients
• Residual medial collateral ligament instability: ~10%
• Superficial infection: <5%
• No motor/sensory nerve complications with proper technique