What is the best management approach for Morrell lesions?

Morel-Lavallée Lesion Management

For Morel-Lavallée lesions, operative management with incision/drainage or formal debridement should be pursued immediately if aspiration yields more than 50 mL of fluid, as this predicts a high recurrence rate (83%) with percutaneous treatment alone. 1

Initial Assessment and Diagnosis

• Morel-Lavallée lesions are closed degloving injuries caused by shearing forces that separate the hypodermis from underlying fascia, most commonly occurring in the thigh, hip, and pelvis regions following high-velocity trauma. 2, 3
• Palpable fluctuance is the most consistent physical examination finding. 2
• High-resolution imaging (ultrasound or MRI) should be obtained to confirm diagnosis and measure lesion volume, as this directly impacts treatment decisions. 1, 4
• Patients on oral anticoagulants develop significantly larger lesions (445.5 cc vs 181.9 cc) and require more aggressive monitoring. 4
• Imaging within 72 hours of injury typically reveals larger lesions (167 cc vs 65 cc) compared to delayed imaging, suggesting early intervention may be beneficial. 4

Treatment Algorithm Based on Lesion Characteristics

Small Lesions (<50 mL fluid on aspiration)

• Perform percutaneous aspiration with culture of aspirated fluid. 2, 1
• Instill doxycycline as a sclerosing agent into the cavity after complete fluid evacuation. 2
• Apply compressive elastic bandaging immediately and maintain continuously for 4-8 weeks. 2
• This approach achieves complete resolution in 94% of cases (15/16 patients) with mean healing time of 4-8 weeks. 2

Large Lesions (>50 mL fluid on aspiration)

• Proceed directly to operative management rather than attempting repeated aspirations, as percutaneous treatment has a 56% recurrence rate in this population. 1
• Operative management includes incision/drainage or formal debridement with wound vacuum-assisted closure placement and/or split-thickness skin grafting. 1, 5
• This approach reduces recurrence to 15% compared to 56% with aspiration alone. 1

Chronic/Persistent Lesions (>6 months duration)

• These lesions have typically been aspirated multiple times (average 3.44 attempts) without resolution. 2
• Doxycycline sclerodesis with strict compression bandaging compliance is effective even for chronic lesions, with complete resolution in all cases at mean 50-month follow-up. 2
• If non-compliance with compression bandaging occurs, repeat the entire procedure rather than continuing failed conservative measures. 2

Critical Management Principles

• All aspirated fluid must be sent for culture to rule out infection, though most lesions are sterile. 2, 1
• The average duration of lesion persistence before definitive treatment is 13 months, indicating these injuries are frequently missed or undertreated initially. 2
• Compression bandaging compliance is essential—failure to maintain compression is the primary cause of treatment failure with sclerodesis. 2
• Most lesions result from motor vehicle collisions (25-66% of cases) and occur in patients with median injury severity scores of 17. 1, 4

Expected Outcomes and Long-Term Sequelae

• With appropriate treatment, no recurrences should occur during long-term follow-up (mean 50 months). 2
• Persistent non-fluctuant contour deformity, decreased skin mobility, and feeling of tightness are common long-term complaints even after successful treatment. 2
• In patients with documented follow-up, 64.5% show persistent but decreasing lesions over time regardless of treatment modality. 4
• All lesions should heal without infection or necrosis when properly managed. 2

Common Pitfalls to Avoid

• Do not perform repeated aspirations (>2 attempts) for large lesions, as this delays definitive treatment and increases morbidity. 1
• Do not underestimate lesion size based on external appearance—imaging is mandatory for accurate volume assessment. 1, 4
• Do not neglect compression bandaging after sclerodesis, as this is the most common cause of treatment failure. 2
• Timely identification is crucial as delayed diagnosis creates infection risk, particularly if associated fractures are present. 3, 5