Morel-Lavallée lesion of the distal thigh: Emergency department diagnosis with point-of-care ultrasound

Abstract

A Morel-Lavallée lesion (MLL) is a rare, closed traumatic soft-tissue degloving injury that is often misdiagnosed. The mechanism that results in this lesion involves a shearing force that separates the hypodermis from underlying fascia, thereby disrupting perforating vascular and lymphatic vessels and resulting in a hemolymphatic fluid collection prone to infection and pseudocyst formation. We describe a case of a 70-year-old male with an initially missed MLL despite CT imaging that was ultimately diagnosed on point-of-care ultrasound (POCUS) on a second emergency department visit. Although an MLL is often misdiagnosed on radiography and CT imaging, POCUS is an expeditious imaging modality that can facilitate diagnosis of an MLL by visualizing specific sonographic characteristics.

Keywords

• Morel-Lavalee
• Knee pain