Management of Morel-Lavallée Lesions
Morel-Lavallée lesions should be managed based on size and chronicity, with lesions containing more than 50 mL of fluid requiring immediate operative intervention rather than aspiration alone due to high recurrence rates. 1
Definition and Pathophysiology
Morel-Lavallée lesions (MLLs) are closed degloving injuries that occur when shearing forces separate the subcutaneous tissue from the underlying fascia, creating a potential space that fills with blood, lymph, and necrotic fat. These lesions most commonly affect the:
- Thigh
- Hip
- Pelvic region
- Knee
Diagnosis
Clinical Presentation
- Soft fluctuant area of swelling
- Pain and tenderness over the affected area
- Possible skin discoloration or bruising
- May present acutely or with delayed onset (days to weeks after trauma)
Imaging
- MRI is the investigation modality of choice 2
- Ultrasound can be used for initial assessment and guided interventions
- CT scan may show fluid collection but is less sensitive than MRI
Management Algorithm
1. Acute Lesions (< 24 hours)
Small lesions without fracture:
- Compression bandaging
- Close observation
- Consider aspiration if symptomatic
Lesions with > 50 mL of fluid on aspiration:
- Proceed directly to operative management 1
- Options include formal debridement, irrigation, and placement of wound vacuum-assisted closure device
2. Subacute/Chronic Lesions (> 24 hours)
Small, asymptomatic lesions:
- Compression therapy
- Observation
Symptomatic lesions:
- First attempt: Percutaneous aspiration with compression
- If > 50 mL fluid aspirated: Proceed to operative management 1
- For recurrent lesions after aspiration: Surgical debridement with or without vacuum-assisted closure
3. Recurrent Lesions
- Surgical debridement with thorough removal of necrotic tissue
- Consider sclerotherapy for recurrent lesions 2
- Options include:
- Tetracycline sclerotherapy 2
- Doxycycline
- Talc
- Alcohol
Operative Techniques
Incision and drainage with debridement:
- Remove all necrotic tissue
- Irrigate the cavity thoroughly
- Consider placement of drains
Vacuum-assisted closure:
- Promotes wound healing
- Reduces dead space
- May require split-thickness skin grafting in extensive cases
Outcomes and Complications
Complications
- Recurrence (56% with aspiration alone vs 15% with operative management) 1
- Infection
- Chronic pain
- Skin necrosis
- Potential contamination of nearby fracture sites 3
Prognostic Factors
- Volume of fluid: Aspiration of >50 mL is associated with 83% recurrence rate 1
- Timing of intervention: Early intervention reduces complications 4
- Location and size of lesion
Follow-up Recommendations
- Regular follow-up until complete resolution
- Monitoring for recurrence for at least 3-6 months
- Repeat imaging if symptoms recur
Key Points
- Early diagnosis and management are crucial to prevent complications
- Aspiration of >50 mL of fluid should prompt operative intervention
- Operative management has significantly lower recurrence rates (15%) compared to aspiration alone (56%) 1
- Recurrent lesions may benefit from sclerotherapy in addition to aspiration