Morel-Lavallée Lesion (MLL) is a posttraumatic, closed degloving injury where 
the skin and superficial fascia get separated from deep fascia (fascialata) in 
the trochanteric region and upper thigh, hence creating a potential space. 
Similar lesions at other locations (e.g., abdominal wall and lumbar regions) 
have been described as Morel-Lavallée effusion, hematoma, or extravasation. 
Injury to an area with rich vascular and lymphatic supply leads to filling of 
this space with blood, lymph, fat, and necrotic debris. MLL usually presents as 
painful fluctuant swelling in the anterolateral portion o fthe upper thigh. Many 
of these maybe missed at initial evaluation and present weeks to months after 
the initial trauma.