Trauma: Morel-Lavallee Lesion

Definition

• Definition: Closed Degloving Soft Tissue Injury
• Skin & Subcutaneous Tissue Separated from the Underlying Fascia
• Shear Injury Causes Disruption of Blood Vessels & Lymphatics
  • Creating Space for Fluid Collection

4-Stages

• Shearing Force Causes Dermal-Fascial Separation
• Fluid Produced from Injured Blood Vessels and Lymphatics
• Fluid Replaced by Serosanguinous Fluid Over Time
• Local Inflammation Causes Pseudocapsule Formation

Presentation

• Classic Presentation: Enlarging Painful Lesion with Swelling & Fluctuance
• Ecchymosis with Pain Out-of-Proportion
• High Risk for Infection (46% Have Bacterial Colonization)
• Risk for Skin Necrosis
• Up to 33% are Missed on Initial Examination

Locations

• Peri-Trochanter Region of Proximal Thigh (Most Common Site)
• Buttock
• Back
• Abdomen

Classification (Mallado and Bencardino)

• *Largely Based on MRI Findings
• Type I: Seroma
• Type II: Subacute Hematoma
• Type III: Chronic Organizing Hematoma
• Type IV: Perifascial Dissection with Closed Fatty Laceration
• Type V: Perifascial Pseudonodulaar Lesion
• Type VI: Infected Lesion

Diagnosis

• CT (Most Common)
• MRI (Preferred in Some Literature
• May Be Seen on US but Less Common

Treatment

• Primary Treatment: Incision & Drainage
  • Any Pseudocapsule Should be Resected to Decrease Recurrence Risk
  • Necrotic Skin Requires Debridement and Possibly Skin Grafting
• Options if Small (< 50 cc):
  • Compression (ACE Wrap or Compressive Bandages)
  • Percutaneous Drainage/Aspiration