Degloving Injury / Morel-Lavallée Lesion Treatment | Recognising the injury

Both can follow the same high-energy shear trauma. In an open injury, skin and tissue are torn away, so doctors can see the wound and usually debride non-viable tissue, use negative-pressure wound therapy, and later reconstruct with grafts or templates. Open injuries carry infection risk that can lead to sepsis and impaired healing, so early surgical care matters. In a closed lesion, the top skin stays intact while deeper tissue separates, creating a space that can fill with blood, lymph and fat; this may be missed at first, especially in polytrauma, and MRI or ultrasound can help detect it. Delayed recognition can allow fluid and necrotic fat to accumulate.

Closed degloving, often called a Morel-Lavallée lesion, happens when shear forces separate skin and fat from the deeper tissue layer, disrupting small blood and lymph vessels. Blood, lymph and fat can collect in that space while the overlying skin remains intact, so the injury may be missed at first, especially when more urgent injuries are treated. These lesions are most common near the top of the hip bone, torso, buttocks, lower spine, shoulder blades or knees, and may appear as bruising or swelling. MRI or ultrasound can help detect it; delayed diagnosis may allow fluid accumulation, tissue death or infection. In polytrauma, life-threatening injuries may be prioritized, so soft-tissue swelling can be overlooked until it evolves.

In a Morel-Lavallée lesion, blunt or high-energy shear separates subcutaneous tissue from underlying fascia and disrupts small blood and lymph vessels. The overlying dermis may look normal, so the injury can be missed, especially after major trauma. Blood, lymph and necrotic fat then collect in the potential space. The lesion often occurs over the greater trochanter, flank, lumbodorsal area, torso, buttocks, lower spine, shoulder blades or knees, and may be associated with pelvic or acetabular fractures. If untreated, swelling can compromise overlying skin and the collection can become encapsulated or infected. Delayed diagnosis can allow accumulation of blood and necrotic fat.

A Morel-Lavallée lesion is a closed degloving injury: the top skin layer stays intact while a space forms underneath and may fill with lymph fluid, blood and fat. Common sites include the greater trochanter, thigh, buttocks, pelvis, torso, lower spine, shoulder blades and knees; similar lesions can occur in any soft tissue under significant shear stress. It is often mistaken for a simple bruise or hematoma, and up to 33% of adult cases may be missed initially, especially in polytrauma. Differential considerations include hematoma, seroma, infection, fat necrosis and neoplasm, so imaging and clinical context matter. Ultrasound can aid screening, while MRI better shows lesion extent, fluid and pseudocapsule.

Unlike a simple bruise, the skin remains intact while deeper tissue separates, leaving a potential space. Imaging is essential: MRI, ultrasound or CT can show fascial plane separation and fluid characteristics. A hematoma may persist chronically with MRI signal inconsistent with acute or subacute blood; seroma is favored by fascial plane separation and trauma history. Lesions often follow high-energy trauma and commonly occur over the greater trochanter, flank or lumbodorsal area, sometimes with pelvic or acetabular fractures. Up to 33% of adult cases may be missed initially in polytrauma. Early recognition matters because delayed diagnosis can allow fluid and necrotic fat accumulation, fibrous capsule formation, recurrence and infection risk.

A Morel-Lavallée lesion is a closed degloving injury in which skin and subcutaneous tissue separate from deeper fascia, creating a space that fills with blood, lymph or fat. Ultrasound is accessible and real-time; lesions appear anechoic or hypoechoic between deep fat and fascia, with echogenicity varying by age, and shapes may be lobulated, flat or fusiform. MRI shows detailed soft-tissue anatomy, fluid collections and fibrous capsules; lesions are typically T2 hyperintense with a T1 hypointense rim. It is particularly useful for chronic lesions, lesions near joints, extent, fluid characteristics and pseudocapsule formation, and for excluding differentials such as DVT. Sensitivity and specificity for MLL diagnosis remain to be clarified.

A Morel-Lavallée lesion is a closed degloving injury where skin and fat separate from deeper tissue, leaving a space that fills with blood, lymph and fat. Delayed diagnosis or a persistent cavity can let a fibrous capsule form. That capsule impedes fluid reabsorption and raises recurrence risk after conservative care. Management is tailored to size, duration, symptoms, recurrence, skin necrosis or infection. Small mild lesions with minimal capsule may be managed with compression and monitoring, sometimes ultrasound-guided aspiration. Chronic lesions with MRI capsule, large volume, recurrent fluid, impairment or failed conservative care generally need surgical intervention, such as capsule excision and drainage.

Degloving injuries avulse skin and subcutaneous tissue from fascia, injuring fasciocutaneous and musculocutaneous perforators. Open injuries often expose fascia and muscles. Morel-Lavallée lesions are closed degloving injuries where shear separates superficial from deep fascia, disrupting vascular and lymphatic channels and creating a potential space for fluid. This can compromise overlying skin viability and increase necrosis risk. Closed lesions may be hidden and sometimes show only bruising, so MRI or ultrasound can help detect them. Lymphoscintigraphy can evaluate lymphatic circulation in circumferential lower-limb degloving. Management depends on lesion size, severity and associated injuries. Early imaging and clinical assessment help guide treatment, limit complications, protect skin viability, and reduce infection risk.

Open degloving injuries are usually serious and need emergency care to reduce blood loss and prevent infection. Closed injuries are harder to diagnose, especially after high-energy trauma, because the dermis stays intact; a bruise may be the only visible sign, yet shearing can separate skin and fat from fascia, creating a Morel-Lavallée space where blood, lymph and necrotic fat collect. That necrotic tissue and haematoma can become an infection source, and swelling may compromise overlying skin if left untreated. An intact dermis can also conceal progressive deep soft-tissue necrosis, so persistent or evolving swelling after high-energy trauma warrants prompt imaging, examination and timely drainage or debridement. Delayed diagnosis can significantly worsen outcomes.

A Morel-Lavallée lesion is closed internal degloving: shearing separates subcutaneous fat from fascia, disrupting small blood vessels and lymph channels, creating a space where blood, lymph and damaged fat collect. It can accompany pelvic, acetabular or instrumented spinal fractures. These lesions may be missed initially in polytrauma patients, and if not addressed promptly they can become encapsulated, prone to infection, and resistant to conservative therapy. Delayed recognition can lead to wound breakdown and hardware problems. Debridement should be planned with fracture fixation to provide soft-tissue coverage. Early MRI or ultrasound, prompt drainage and staged debridement can help before a pseudocapsule forms. Careful multidisciplinary coordination is essential.