What is the initial management for a Morel-Lavallee lesion?

Management of Morel-Lavallée Lesions

The initial management for a Morel-Lavallée lesion should include percutaneous aspiration with compression bandaging, but if the aspirated fluid volume exceeds 50 mL, surgical intervention is recommended due to high recurrence rates. 1

Pathophysiology and Clinical Presentation

• Morel-Lavallée lesion (MLL) is a closed degloving injury that develops when shear forces separate the hypodermis from the underlying fascia, creating a potential space that fills with blood, lymph, and necrotic fat 2, 3
• These lesions most commonly occur in the trochanteric area, pelvis, and thigh regions, but can also appear in other locations such as the proximal calf 3, 4
• The most consistent clinical finding is an area of palpable fluctuance over the affected region 2

Diagnostic Approach

• Diagnosis is primarily clinical but should be confirmed with imaging studies 4
• Ultrasonography typically reveals a homogeneous, hypoechoic fluid collection between the subcutaneous tissue and underlying fascia 3
• MRI is the gold standard imaging modality, showing fluid of homogeneous signal intensity between the subcutaneous layer and the underlying fascia 3, 4

Treatment Algorithm

Initial Management:

1. Percutaneous aspiration with compression bandaging 2, 1, 5

   • Send aspirated fluid for culture to rule out infection 2
   • Apply compressive elastic bandaging after aspiration 2

2. Decision point based on aspirated fluid volume:

   • If aspirated fluid is >50 mL: Proceed to surgical intervention due to high recurrence risk (83% recurrence rate) 1
   • If aspirated fluid is <50 mL: Continue with compression and observation (33% recurrence rate) 1

For lesions with <50 mL aspirate:

• Continue compression bandaging for at least 4-8 weeks 2
• Monitor for resolution with follow-up ultrasonography 2, 5
• If persistent after initial aspiration, consider repeat aspiration with sclerodesis 2

For lesions with >50 mL aspirate or recurrent lesions:

• Surgical intervention is recommended 1, 3
• Options include:
  • Radical excision of the lesion with suturing of superficial to deep fascia to prevent shearing 3
  • Incision/drainage with formal debridement of skin and soft tissues 1
  • Wound vacuum-assisted closure placement and/or split-thickness skin grafting may be required in extensive cases 1

Sclerodesis Option

• For persistent lesions that fail initial aspiration, doxycycline sclerodesis can be considered 2
• Technique involves:
  1. Complete aspiration of fluid
  2. Doxycycline instillation into the cavity
  3. Compressive elastic bandaging
  4. Follow-up at 4 weeks to assess resolution 2

Monitoring and Follow-up

• Follow-up should continue until complete resolution is confirmed clinically and by imaging 2, 5
• Resolution is defined as loss of fluctuation with complete absence of fluid on ultrasonography 2
• Most lesions resolve within 4-8 weeks with appropriate treatment 2

Potential Complications

• Recurrence is the most common complication, especially with conservative management alone (56% recurrence rate with aspiration vs. 15% with operative management) 1
• Long-term sequelae may include persistent non-fluctuant contour deformity, decreased skin mobility over the site, and feeling of tightness 2
• Risk of infection if left untreated, particularly concerning when associated with fractures 4

Special Considerations

• Pediatric cases are rare but have been successfully treated with serial ultrasound-guided percutaneous drainage and compression bandages 5
• Patient compliance with compression bandaging is crucial for successful treatment outcomes 2